all assignments completed

9 Professional Ways to Say 'I Have Completed My Work'

When it comes to communicating that you have completed your work in a professional manner, it's important to choose your words carefully. Saying 'I have completed my work' can sound quite basic and might not convey the level of professionalism you desire.

Here are nine alternative phrases you can use to sound more professional:

• I have finished the task at hand
• The work has been successfully accomplished
• I have concluded my duties
• The project is now complete
• I have fulfilled my responsibilities
• All the required tasks have been executed
• I have wrapped up the assignment
• My work here is done
• I have reached the final stage of this project

Let's explore each alternative phrase with examples to understand their usage better:

1. I have finished the task at hand

This phrase is a more professional way of saying 'I have completed my work.' It emphasizes that you have accomplished a specific task or assignment.

Example: 'I want to inform you that I have finished the task at hand and it is ready for review.'

2. The work has been successfully accomplished

Using this phrase showcases that you have not only completed your work but have done so successfully. It highlights your competence and professionalism.

Example: 'I am pleased to inform you that the work has been successfully accomplished and is now ready for presentation.'

3. I have concluded my duties

This phrase conveys a sense of responsibility and commitment to your assigned tasks. It implies that you have fulfilled your obligations.

Example: 'I am writing to let you know that I have concluded my duties and all necessary documentation has been submitted.'

4. The project is now complete

When referring to a project, using this phrase indicates that you have finished all the required tasks and the project is ready for the next stage or delivery.

Example: 'I am happy to announce that the project is now complete and we can proceed with the final review.'

5. I have fulfilled my responsibilities

This phrase emphasizes that you have fulfilled your role and responsibilities in a particular project or task. It shows a strong sense of accountability.

Example: 'I take pride in informing you that I have fulfilled my responsibilities and the results are in line with the agreed-upon objectives.'

6. All the required tasks have been executed

Using this phrase indicates that you have completed all the necessary tasks associated with a project or assignment.

Example: 'I would like to update you that all the required tasks have been executed as per the project timeline.'

7. I have wrapped up the assignment

This phrase suggests that you have completed and finalized an assignment or task, ready to move on to the next phase or submit it for review.

Example: 'I'm happy to inform you that I have wrapped up the assignment and it is now ready for your evaluation.'

8. My work here is done

Using this phrase conveys a sense of accomplishment and finality. It indicates that you have completed your work and there is nothing further to be done from your end.

Example: 'With great satisfaction, I can say that my work here is done, and I am available to assist with any other tasks as needed.'

9. I have reached the final stage of this project

This phrase is suitable when referring to a project with multiple stages. It signifies that you have successfully completed all the previous stages and have reached the final stage.

Example: 'I am delighted to inform you that I have reached the final stage of this project, and we are ready for the project review meeting.'

By using these alternative phrases, you can effectively communicate that you have completed your work in a professional and impressive manner.

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Completed all assignments till week2 #22

Are you sure you want to change the base, conversation.

suleman1412 commented Aug 18, 2024

Completed all assignments till week2, also did additional assignment of making Promisified versions of setTimeout, fetch, fs.readFile and a problem statement I came up myself.

• Write a function which tries to read a file asynchronously but throws an error it takes more than certain amount of time/ mili seconds.

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How can I tell my manager that I completed the work he assigned? [closed]

I am learning English and feeling very difficulty in framing sentence. I need following sentences into proper sentence please help me in this.

Yesterday my manager as assigned some work to do and today I completed that work. I have to inform my manager that I completed the task and attached the documents regarding assignment.

• For the record, do not ask a question here and on ELU . And do not expect that a question here will necessarily be answered here within a matter of minutes . –  J.R. ♦ Commented Jan 9, 2014 at 23:44

3 Answers 3

I'm interpreting your question as to how to inform your manager you have done what he asked you to do. Hence,

I've completed the work/task/project/assignment you required and attached the necessary documents.

• 1 I would probably use the word assigned instead of required , and I'd include an extra "have": I've completed the work/task/project you assigned and have attached the necessary documents. (This doesn't mean I disagree with your answer; it simply means there is more than one way to say just about anything, and some of it will inevitably come down to stylistic preferences.) –  J.R. ♦ Commented Jan 9, 2014 at 12:20

As I answered on the other site already, a simple solution is almost what you wrote:

Dear [manager], I completed the task and attached the documents related to the assignment.

If you want to elaborate a bit, you could write something like:

Dear [manager], I have finished the assignment you gave me yesterday. Please find attached the documents I prepared for this assignment. Kind regards, Praveen

• "...and attached the documents regarding the assignment" doesn't sound quite right. Perhaps use "relating to" rather than "regarding". Also, because you're attaching the documents to the e-mail now, rather than in the past, it should be simple present. Hence: "...and attach the documents relating to the assignment." –  Steve Melnikoff Commented Jan 9, 2014 at 15:26
• It's probably a matter of opinion, but "assignment" sounds like something you're given to do at school. Perhaps "task" is better in a work environment. –  Steve Melnikoff Commented Jan 9, 2014 at 15:27
• I have heard assignment being used in out-of-school contexts a lot among my Indian colleagues, so I have to admit I do not stumble on that anymore :) As for "regarding", yes, maybe your suggestion works a bit better. –  oerkelens Commented Jan 9, 2014 at 15:28

I'll offer an edited version of your whole question just in case that helps; your English is pretty clear already!

I am learning English and experiencing a lot of difficulty in framing a sentence. I need to edit the following sentences into proper sentences. Please help me with this. Yesterday, my manager assigned me some work to do, and today I completed that work. I have to inform my manger that I completed the task, and have attached the documents regarding the assignment.

• 1 In response to your version of the question: He's not really asking for anyone to “edit” the sentences that follow, but rather to help him express the information they contain to a third party. Nice work otherwise. –  Tyler James Young Commented Jan 9, 2014 at 14:44
• To "express the information," he had to edit them. I just threw that particular word (along with "to" and "the") in as one of multiple possible ways of resolving the meaning of that sentence. –  Nick Stauner Commented Jan 9, 2014 at 14:49

Not the answer you're looking for? Browse other questions tagged grammar word-usage .

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How to complete when you have lots of assignments ?

Assignment Juggling Mastery: Strategies to Efficiently Navigate and Excel When Facing a Pile-Up of Academic Tasks.

When faced with a heavy workload of assignments, effective planning and execution are key to success. Managing multiple assignments requires strategic prioritization, efficient time management, and a structured approach to ensure quality and timely completion. This guide explores practical steps to tackle numerous tasks: from breaking down assignments into manageable parts and creating a schedule, to staying organized and minimizing distractions. By implementing these strategies, students can enhance productivity, reduce stress, and achieve academic goals effectively. Balancing thoroughness with efficiency, this approach fosters not only completion but also mastery of content, empowering students to excel amidst demanding academic schedules.

Strategic Implementation for Enhanced Productivity and Academic Success

Implementing these strategies enhances productivity, reduces stress, and achieves academic goals effectively. Balancing thoroughness with efficiency fosters both completion and content mastery, empowering students to excel amidst demanding academic schedules.

1. Prioritize Your Assignments:

- Start by identifying which assignments are due. Prioritize them based on deadlines. Consider factors like the complexity of the assignment, the amount of research required, and your familiarity with the topic.

2. Break Down Each Assignment:

- Divide each assignment into smaller, manageable tasks. It could include researching, outlining, writing, revising, and proofreading. Breaking down assignments into smaller steps makes them less intimidating.

3. Create a Schedule:

- Develop a detailed schedule or to-do list that outlines when you'll work on each assignment. Allocate specific time slots for research, writing, and editing. Be realistic about the time needed for each task.

4. Set Goals:

- Establish daily or weekly goals for completing portions of your assignments. Setting achievable milestones will help you stay on track and motivated.

5. Minimize Distractions:

- Find a quiet and focused workspace to minimize distractions. Turn off social media notifications and other distractions while working on assignments.

6. Use Time Management Techniques:

- Techniques like the Pomodoro Technique (working in focused intervals with short breaks) can improve productivity and prevent burnout.

7. Start Early:

- Begin working on assignments as soon as they are assigned. Procrastination can lead to stress and lower-quality work.

8. Utilize Resources:

- If you encounter challenges with a particular assignment, seek help from professors, or you can opt for platforms offering Assignment Help USA . Don't hesitate to ask questions when you're unsure about a task.

9. Stay Organized:

- Keep all your assignment-related materials well-organized, including research notes, outlines, and drafts. Use digital tools or physical folders to manage your resources.

10. Avoid Multitasking:

- Focus on one assignment at a time. Multitasking can reduce the quality of your work and increase stress levels.

11. Take Breaks:

- Allocate short breaks between tasks to recharge your mind. Use this time to stretch, walk, or do something enjoyable to prevent burnout.

12. Stay Healthy:

- Maintain a balanced diet, exercise regularly, and get enough sleep. Physical and mental well-being are crucial for effective time management and productivity.

13. Review and Revise:

- After completing an assignment, take the time to review and revise your work. Check for errors and improve the overall quality of your assignment.

14. Seek Extensions if Necessary:

- If you encounter unexpected challenges or circumstances that hinder your ability to complete an assignment on time, consider requesting an extension from your professor. Be sure to provide valid reason/reasons and request it before the deadlines mentioned in the instructions.

15. Celebrate Your Achievements:

- Acknowledge your accomplishments along the way. Reward yourself for meeting milestones and completing assignments. Positive reinforcement can boost motivation.

You must remember that effective time management and organization are crucial to completing multiple assignments successfully. Following these steps and maintaining a proactive approach to your coursework can reduce stress and produce high-quality work within your deadlines.

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The 5 Best Assignment Help Websites for College Students

The popularity of professional assignment help websites has grown significantly during the pandemic times when most students had to make a complex shift and start with their online studies.

There were numerous challenges that had to be faced, including heavy workload issues, misunderstanding of the grading rubric, and academic pressure.

The majority of students approach online help as a way to avoid plagiarism and receive better grades as they share their concerns with trained experts.

Still, finding the best assignment help services can be quite challenging!

Check out a list of reliable assignment help offerings online aimed at college students!

The Best Assignment Help Websites for College Students

1. assignmentbro.

Company’s History. This friendly company belongs to relatively new offerings, yet they have already earned the hearts and minds of school and college students worldwide. They are reputable and always place the client’s needs first, as they are managed by a great team of university graduates who know what students are going through.

Reliability. A plethora of online reviews and the presence of direct contact with a writer makes them reliable. There are free revisions and refunds available as well. Moreover, there are excellent citation tools and writing tools for paraphrasing, a words-to-minutes converter, and a conclusion generator.

Quality of Assignments. Our Law assignment has been delivered on time, and the paper has been free of grammar or style mistakes. The formatting has been done properly, and the content itself has been done professionally with all citations in place.

Prices. As we looked for the best assignment services, we wanted to approach only the most affordable services where the quality still remains high. At AssignmentBro, they do not have a fixed price, which is a good thing because you can negotiate the final price. Our price depended on our subject, the qualification of the writer, and the deadline. It was affordable!

Reviews. Their Sitejabber page shows that they have 4.7 stars based on 53 reviews. People praise them for their affordability and their friendly attitude. The Trustpilot page has 4.4 stars based on 29 reviews. Their writers are always praised as well as their support team.

Customer Support. It deserves six stars out of five because they are the most caring and friendliest when it comes to getting your challenges fixed.

Why Choose It? A young company that is aimed at getting you understood as you ask for academic writing help. Affordable and high-quality writing with a plethora of helpful free tools.

2. A Research Guide

Company’s History. This great service has been around for more than 10 years now, yet they are rarely mentioned when the best assignment writing services are mentioned. The reason for that is that they are not your typical company because it is a great hub for all things research writing. They offer free materials, tutorials, and templates even before you place an order.

Reliability. They cooperate with numerous institutions and businesses as they offer innovative research paper writing assistance and explore all the latest and most efficient ways to deliver excellent research. They have won several awards in the field and represent a fully legit service.

Quality of Assignments. This is where they truly stand out, as their specialists will ask you all the possible questions before they match you with a specialist in their field. We have approached them for a Political Sciences research paper, and they have delivered an excellent paper with credible sources, formatting, and high-quality research.

Prices. The prices start at $14.99 per page and belong to more expensive writing solutions. Still, when you think about the direct communication and assistance that you receive, it’s totally worth it.

Online Reviews. This is where things get rather rough, as the number of reviews is extremely limited. Still, we could find out feedback from professional educators, online course creators, and dissertation-writing students who needed complex research. Their testimonials speak in favor of the company’s reputation.

Customer Support. The support agents represent experienced researchers who will happily guide you through the website and help you with anything. They are available 24/7.

Why Choose It? Look no further if you need serious research paper writing help and want to enjoy freebies that will help you to deliver a perfect assignment.

3. EduBirdie

Company’s History. The company is one of the most famous names in the industry. Their website states that they have been offering legit academic help since 2014. The company runs a blog and stands at the top of technical and academic innovations.

Reliability. They let you talk to your writer directly and provide free paper revisions. If you are not happy with the paper, they offer full refunds. The reviews online show that they are safe to use and follow their promises.

Quality of Assignments. Speaking of online assignment help websites, they offer timely delivery and focus on anything from essay writing and dissertations to personal statement writing and online exams. Placing an order with them, our experts received expert assistance, and the paper contained no grammar, style, or plagiarism issues.

Prices. The prices here start at $13.99 per page and remain affordable if we compare these services to similar offerings online. They implement a bidding system so your final price will depend on the writing quality chosen, the subject, the deadline, and the popularity of your subject.

Online Reviews. This company is constantly mentioned on Sitejabber, Trustpilot, and YouTube (they have their channel), and they are popular among social media users. They are rated at 4.7 out of 5 total points, which is a sign of reliability. Most of their clients are happy with the results.

Customer Support. They are trained well and respond immediately. We had a nice experience talking to the support agents. They are available 24/7 and offer human help with no bots.

Why Choose It? The positive reputation of the company and the chance to talk to your writer directly place them at the top of the most popular assignment help websites you can find these days. They are plagiarism-free and offer reliable quality at an affordable price.

4. SameDayPapers

Company’s History. The company has been around since 2017 and started out in Great Britain and Australia. Later on, they added affordable writing help services in the United States as well. They are the best choice if you are an ESL student or a learner looking for complex custom assignments that focus on Sociology, Psychology, History, or Engineering.

Reliability. They offer free paper revisions and also provide you with a free tool to check your grammar. Regarding the plagiarism, they also let you check things free of charge. Employing native English speakers, they are very strict about their writers and let you cooperate with verified specialists.

Quality of Assignments. Placing an order is easy and logical here, which clearly shows that we are dealing with the best website for assignment help. Checking the paper on Psychology, we can state that it has been delivered even earlier than our deadline. The paper was original, had excellent formatting, and the content has been up to the highest standards.

Prices. They represent an affordable and the best website to do assignments, with their prices starting at $12.99. If you are looking for reliable editing services, the prices will start at $5.5 per page.

Online Reviews. Researching this company’s background, we could locate over two hundred reviews. Most of them are positive and come from the United States, the UK, and Australian users. The total rating is 4.38/5 points.

Customer Support. It’s available for American users, and they respond right away by assisting you with anything from placing an order to finding a specialist that matches your needs.

Why Choose It? It’s one of the global companies that implement verified writers and can offer professional assistance. There are also UK and Australian branches, should you need specific help or sources.

5. EduZaurus

Company’s History. The story of this amazing sample essay database and academic writing company dates back to June 2015. Since then, they have collected a great resource for students coming from all disciplines. The company’s website claims that they have completed over 100,000 assignments as 2021 has started. They provide hundreds of skilled writers, yet what makes them unique is a great collection of free essay samples. It makes them one of the best choices when you need inspiration.

Reliability. Offering legit academic assistance, they can be safely marked as the best assignment writing help service for their collection of samples alone that showcases their work and provides a general idea of what can be expected. There are free revisions and refunds.

Quality of Assignments. Placing an order for the coursework paper in Journalism, we received an excellent document that has been formatted correctly and contained high originality. The grammar and style have been done well. The delivery has been set to only eight hours, yet the paper has been delivered on time.

Prices. Since there are many factors that affect the price per page (writer’s level, your deadline, task specifics), our price has started at $25 per page, yet the general pricing can vary between $20 and $50 if your order is urgent. The prices with a longer deadline start at $12.99 per page. Remember that you should always wait for the best bids to appear.

Online Reviews. Sitejabber users gave them 4.52 stars out of 5 based on 29 reviews. As for TrustPilot, they’ve earned 4.3 out of 5 stars based on 15 testimonials. Most people praise them for being legit and trustworthy.

Customer Support. They have an online chat feature, which is available 24/7. The support remains friendly even if you run into problems.

Why Choose It? This service is the best choice when it comes to finding free samples for inspiration, yet their writing assistance is also up to the highest standards. They cover a wide range of subjects and have a minimum deadline of 3 hours that actually works.

Where Can I Find Trustworthy Assignment Help?

You can find it online, as there are numerous offerings.

As a way to save time, we have tested and evaluated five of the best homework help websites that can be trusted.

Take your time to explore them and see which of them fits your academic needs first.

What is The Best Assignment Help Website You Can Recommend?

While the “best” is always subjective, you may safely check these five entries explored above.

Each of them is different and provides specific benefits in each case

A Research Guide service is the best choice for research paper writing, while EduZaurus will provide you with a great selection of free samples!

Is Assignment Help Described Legit?

Absolutely! Every assignment help website on our list has been tested in terms of being legit .

These services are acknowledged providers of academic help online and are absolutely safe to use, as many online reviews can confirm.

Sharing Your Instructions Well is Essential!

As you are looking through websites that do your homework online, remember that you should always start with careful preparation and sorting of your instructions.

These must be shared with a chosen specialist and have a clear description because it is the only way to achieve success and the necessary degree of clarity.

Although many services like EduBirdie or AssignmentBro let you talk to your writer directly, you must be precise with your instructions and share anything from the assignment grading rubric to the comments and recommendations from your college professor.

It will help you to get the best quality and save time as you avoid mistakes and explain what you expect to see as you place your assignment request.

Regardless if you require research paper writing services or seek an expert who can proofread your work and fix grammar mistakes, sharing your instructions should always come first!

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14 Proven Tips For Completing Assignments

Completing assignments can be a daunting task, but there are a few things that you can do to make the process a whole lot easier. 

Are you finding it difficult to complete your assignments on time? If you’re looking for some tips to help you get organized and stay on track, you’ve come to the right place. In this post, I’ll share some helpful strategies that will make completing your assignments a breeze.

Why are assignments important?

Though often met with groans and complaints, academic assignments are actually beneficial in a number of ways. For one, they force students to engage with the material on a deeper level, encouraging them to really think about what they’re learning and stay on track with their studies.

In addition, academic assignments help students to develop important research, writing and study skills that will be useful in college and beyond.

Academic assignments also give students the opportunity to receive feedback from their instructors on their work.

Notably, despite its benefits, too many assignments can do more harm than good.

Too much assignments can interfere with free time and involvement in extra-curricular activities. Assignment completion may be increasingly frustrating and stressful when there are challenges with the home environment. O’Rourke-Ferrara, 1998

Why is completing assignments on time important?

Completing assignments on time demonstrates to your instructor that you are capable of meeting deadlines. This is important in both academic and professional settings.

According to research, completing assignments improves independence, self-discipline, and time management skills. In addition, it has been linked with better grades and academic success. planchard et al., 2015

Tips for completing assignments

So how can you make sure that you complete your assignments on time? Here are a few tips that may help:

1. Read the assignment instructions carefully

2. identify why the assignment is necessary.

It gives purpose to your efforts, and this in turn can help provide focus and direction, leading to better results through hard work and dedication.

Research shows that the main motivating factors for homework completion were: (1) Reinforcement: desire to learn or master the material (2) Credit (3) Extra-credit planchard et al., 2015

3. Start early to complete assignments on time

4. set goals for assignment completion.

Once you’ve met that goal, you can set a new goal for the next day. Breaking the assignment down into smaller tasks can help to make it feel less overwhelming, and it can also help you to track your progress. 

5 . Create a schedule to finish assignments

Research shows that the most common demotivating factors for homework completion were: (1) Other commitments (2) Difficulty understanding (3) Too difficult or too long planchard et al., 2015

6. Identify the resources required for the assignment

7. track your reference s when researching.

As you’re doing research for your assignment, be sure to track the references that you’re using. This will save you time when you’re writing your paper and will ensure that you give credit to the sources that you’ve used.

8. Set aside uninterrupted time for assignments

9. ask for help if you get stuck, 10. take breaks when completing assignments.

Working on an assignment for long periods of time can be overwhelming and lead to burnout. To avoid this, take breaks throughout the day or week. during your break, do something that you enjoy or that will help you relax.

11. Celebrate your progress

12. proofread your assignments, 13. submit your assignments on time.

Make sure to submit your assignment on time. If you’re having trouble with this, talk to your professor or a tutor. They may be able to offer extension or help you get back on track.

14. Relax after completing each assignment

Final words on proven tips for completing assignments.

Drop a comment below and let me know. Best of luck in all your future assignments.

Planchard, Matthew S. et al. “Homework, Motivation, and Academic Achievement in a College Genetics Course.”  Bioscene: The Journal Of College Biology Teaching  41 (2015): 11-18. https://files.eric.ed.gov/fulltext/EJ1086528.pdf

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By submitting my email address. i certify that i am 13 years of age or older, agree to recieve marketing email messages from the princeton review, and agree to terms of use., 8 easy ways to finish your homework faster.

How many times have you found yourself still staring at your textbook around midnight (or later!) even when you started your homework hours earlier? Those lost hours could be explained by Parkinson’s Law, which states, “Work expands to fill the time available for its completion.” In other words, if you give yourself all night to memorize those geometry formulas for your quiz tomorrow, you’ll inevitably find that a 30 minute task has somehow filled your entire evening.

We know that you have more homework than ever. But even with lots and lots to do, a few tweaks to your study routine could help you spend less time getting more accomplished. Here are 8 steps to make Parkinson’s Law work to your advantage:

1. Make a list

This should be a list of everything that has to be done that evening. And we mean, everything—from re-reading notes from this morning’s history class to quizzing yourself on Spanish vocabulary.

2. Estimate the time needed for each item on your list

You can be a little ruthless here. However long you think a task will take, try shaving off 5 or 10 minutes. But, be realistic. You won’t magically become a speed reader.

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3. Gather all your gear

Collect EVERYTHING you will need for the homework you are working on (like your laptop for writing assignments and pencils for problem sets). Getting up for supplies takes you off course and makes it that much harder to get back to your homework.

The constant blings and beeps from your devices can make it impossible to focus on what you are working on. Switch off or silence your phones and tablets, or leave them in another room until it’s time to take a tech break.

Read More: How to Calculate Your GPA

5. Time yourself

Noting how much time something actually takes will help you estimate better and plan your next study session.

6. Stay on task

If you’re fact checking online, it can be so easy to surf on over to a completely unrelated site. A better strategy is to note what information you need to find online, and do it all at once at the end of the study session.

7. Take plenty of breaks

Most of us need a break between subjects or to break up long stretches of studying. Active breaks are a great way to keep your energy up. Tech breaks can be an awesome way to combat the fear of missing out that might strike while you are buried in your work, but they also tend to stretch much longer than originally intended. Stick to a break schedule of 10 minutes or so.

8. Reward yourself! 

Finish early? If you had allocated 30 minutes for reading a biology chapter and it only took 20, you can apply those extra 10 minutes to a short break—or just move on to your next task. If you stay on track, you might breeze through your work quickly enough to catch up on some Netflix.

Our best piece of advice? Keep at it. The more you use this system, the easier it will become. You’ll be surprised by how much time you can shave off homework just by focusing and committing to a distraction-free study plan.

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10 Tips from Experts for Completing Assignments on Time

David Lucas

Assignments are essential to learning in the modern era, giving students freedom and ease. However, with this ease comes the challenge of properly organizing your time to ensure all tasks are finished before the deadline. So, to help you navigate all aspects of learning online, experts from assignment writing service platforms have collected tips to help you complete your projects on time.

In an ever-changing educational realm, the rise of the internet in education brings both comfort and difficulties to learners. Although online classrooms allow students to adjust to the way they learn, they must also have a greater sense of duty, particularly when it comes to finishing tasks on time. Handling the complexities of tasks online needs an organized strategy and a good plan.

Tips to Complete Assignments Quickly

The following tips have been made to be easy to use, giving you an outline for achieving success in an online educational setting. They cover everything from building a well-organized timetable to using technology and protecting your overall health. Whether you are a skilled digital student or just starting, these tips will help you face assignments calmly and efficiently. Let’s look at some expert tips and ways that can improve the way you learn online:

• Make a Plan: The first step is to plan your approach. Experts strongly believe that making a timetable is extremely important for good time management. Begin by dividing up the task into parts and giving time frames for all of them. This is the only way to go about doing work, according to an expert. It simply makes your task a little easier, and it also helps you to concentrate better.
• Set Realistic Goals: Experts believe that setting realistic targets and goals is key to maintaining the quality of the work. Be aware of what you can do and set realistic goals, keeping in mind your strengths and strong points. This avoids delays and guarantees that you don’t pull up extra threads to make it cool or different. Goals that are clear, specific, and possible can help you stay organized and inspired without making you tired of the work.
• Avoid Distractions: Try creating a safe and inspiring space to focus and pump up good ideas. Experts stress the need to avoid distractions as much as possible while working to create good-quality work. Be mindful of the time and manage it accordingly. Distractions can greatly affect one’s ability to finish tasks on time; therefore, creating an enjoyable and calm working environment is important.
• Make Use of Technology: In this new and exciting digital age, it is easy to get carried away, especially while working. Hence, many online apps and sites could help you navigate this stimulating corpus and keep you focused. A lot of tools have been designed for this specific problem; try finding the one you like and get back on the grind. Or you could simply ask someone, “Can you do my assignment for me ?” to get some help online.
• Start the Work Early: Start doing the task as soon as you get it. Furthermore, it lessens the anxiety and overall stress, but it also allows an extra-careful and focused attitude towards the task. Timely starts offer more time for changes and editing. If you think you don’t have enough time and might need some help, don’t be shy about asking for it. You could get some professional advice only if you look up assignment writing service, to get online help.
• Break Down Difficult Tasks: Experts very well believe that further breaking down complex tasks gives clarity and allows you to see the problem. Experts advocate dividing challenging tasks into smaller, simpler tasks and then dividing them into multiple parts as a healthy way to work on them. Working on one part makes the whole thing less scary. Additionally, it makes way for more logical and fresh ideas. Working in smaller chunks also helps you focus better, allowing you to give your best.
• Prioritize Tasks : Setting priorities is a key component of managing your time. Find activities by urgency and significance. Important things should be tackled first to make sure that vital parts are finished on time. Setting goals helps make good use of both resources and time.
• Create a Routine: Setting a routine helps in making progress. Working on the sections and making them a part of the schedule will make things easier. Set up a daily schedule that involves regular research and writing hours. This practice trains the brain to pay attention during given periods, which makes it easy to switch to study mode.
• Ask for Clarity: If you have any doubts or worries about the task, do not hesitate to ask for explanations. Miscommunications can lead to mistakes. Early on, get clarity from your lecturers or classmates to verify that you’re on the correct path. It also, in a way, lets you work in peace, knowing what the question is demanding. In a way, it increases productivity and saves one from making a grave error.
• Taking Breaks: Finally, experts highlight the value of maintaining overall well-being. A strong mind and body lead to higher productivity. To avoid stress, make sure that you get enough rest, work out often, and take breaks in between. Mental and physical health are keys to efficient time management. It also keeps you energized and more focused on the work.

Of course, these tips will make your task easier, but it is also important to keep in touch with your mentor. They can solve specific topic-related issues in a whiff. Online learning can be uneasy sometimes, and it is important to make your presence felt in the class. Try asking for feedback from your mentor, and surely, you’ll get better help without wasting your time looking up things online. Also, be confident and vocal and learn as much as you can from this unique learning experience.

To summarize, finishing online projects on time needs an equal amount of good organization, effort, and a sense of self. By following these excellent tips, you can not just regularly meet goals but also improve the standard of your assignment. Understand that effective planning is a talent that can be learned and honed with diligence and practice. Get some help from the assignment writing service online, if needed. The internet is full of ideas and tips to help you. Good luck and happy assignment writing!

Written by David Lucas

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4 Tips for Completing Your Homework On Time

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• B.A., English, University of Michigan

Homework, a necessary evil according to many teachers, has a lot of students tied up in knots. Some students can never seem to get things turned in on time. In fact, many students do not even realize that they  have  homework until a friend from class texts them or they overhear someone in the halls talking about Ms. So-and-so's terrible, no-good, awful, horrifying worksheet for Chemistry that is due the next day. These five tips for completing your homework on time, however, should help you get that homework finished on time. 

Tip 1: Rely On a Planning System

Most of you by now are well acquainted with a homework planner. It has the dates, the school subjects you are taking, and a whole lot of blank space to write down your homework assignments. Use these planners if you have them. Writing with an actual pencil or pen may seem almost archaic what with technology virtually doing everything for us, but the kinesthetic movement of writing down an assignment into one of those little squares (Language Arts test tomorrow - STUDY TONIGHT), will actually help solidify that homework in your brain.

Plus, when you are packing up to go home at the end of the school day, all you have to do is open up that planner to see which books, folders, and binders need to go home with you so you will not miss out anything that you need to do that evening.

Some people  hate  using planners. They'd rather walk on a pile of crushed glass than actually write something down in a planner. That's quite all right. One student kept a wadded up piece of paper in his pocket where he'd scrawl his assignments. It worked for him, so it was fine. For those of you not keen on planners or crumpled up notes, your phone can come in really handy. Just download a productivity app and type your assignments in there. Or, keep track of all the work due in the notes section of your phone. Or, snap a picture of the homework board in each teacher's class before you head out into the hallway. Or, if you are really dead-set against anything planner-related, then just send yourself a text after each class with your homework assignments for the night.

No matter which planning system you prefer, use it. Check off each item once you get it in your backpack. Your brain can only process so much information at a time, so you absolutely must write your homework down if you plan to complete it on time. 

Tip 2: Prioritize Your Homework Assignments

All assignments are not created equal. It's strongly recommended you use a prioritizing system when you sit down at home with your homework. Try a system a little something like this:

• Examples: Studying for a major test coming up tomorrow. Finishing a major project due tomorrow. Writing an essay worth a LOT of points that is due tomorrow. 
• Examples:  Studying for a quiz coming up tomorrow. Completing a homework sheet that is due tomorrow. Reading a chapter that is due tomorrow. 
• Examples: Studying for a spelling test that will occur on Friday. Writing a blog and posting it on the class board by Friday. Finish a book upon which you will take a quiz on Friday.
• Examples: Reviewing chapters for the midterm exam. Working on an on-going project, research paper, or long assignment due at the end of the quarter. Completing a packet that isn't due for two weeks. 

Once you've prioritized the work you have to do, complete all the 1's first, then the 2's, moving down as you go. That way, if you find yourself pressed for time because Great-Grandma decided to stop over for family dinner and your mom insisted you spend the evening playing bridge with her despite the fact that you have hours of homework ahead of you, then you will not have missed anything vitally important to your grade. 

Tip 3: Get the Worst Assignment Over With First

So, maybe you absolutely hate writing essays (But, why, though when all you have to do is follow these essay tips? ) and you have a major essay staring you in the face that  must  be completed before tomorrow. You also have to study for a major math test, complete a social studies blog by Friday, study for the ACT  next month, and finish up your science worksheet from class. Your "1" assignments would be the essay and the math test. Your "2" assignment is the science worksheet, the "3" assignment is that blog, and the "4" assignment is studying for the ACT. 

Ordinarily, you would start with the science worksheet because you  love  science, but that would be a big mistake. Start with those "1" assignments and knock out that essay first. Why? Because you hate it. And completing the worst assignment first gets it off your mind, out of your homework cache, and makes everything that comes after it appears to be really, really easy. It will be an absolute  joy  to complete that science worksheet once you have written the essay. Why rob yourself of joy? 

Then, once you've completed the stuff due first, you can focus on putting in a little bit of time on the ACT. Easy peasy.

Tip 4: Take Planned Breaks

Some people believe that sitting down to complete homework means that you literally park your behind in a chair and you don't move it for the next four thousand hours or so. That is one of the worst study ideas in history. Your brain only has the capacity to stay focused for about 45 minutes (maybe even less for some of you) before it goes on the fritz and starts wanting to make you get up and dance the Roger Rabbit. So, schedule your study time with breaks actually built in . Work for 45 minutes, then take a 10-minute break to do whatever it is people your age like to do. Then, rinse and repeat. It looks a little something like this:

Homework Time:

• 45 minutes: Work on "1" assignments, starting with the absolute worst.
• 10 minutes: Get a snack, play Pokemon Go!, surf Instagram
• 45 minutes: Work on "1" assignments again. You know you didn't finish.
• 10 minutes: Do some jumping jacks, dance the Macarena, polish your nails.
• 45 minutes: Work on "2" assignments and maybe even finish with any 3s and 4s. Put everything in your backpack.

Completing your homework on time is a learned skill. It requires some discipline and not everyone is naturally disciplined. So, you have to practice checking that you have everything you need for homework when you are still at school, prioritizing your work, plunging into the assignments you loathe, and taking planned breaks. Isn't your grade worth it?

You bet it is. 

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Understanding Assignments

What this handout is about.

The first step in any successful college writing venture is reading the assignment. While this sounds like a simple task, it can be a tough one. This handout will help you unravel your assignment and begin to craft an effective response. Much of the following advice will involve translating typical assignment terms and practices into meaningful clues to the type of writing your instructor expects. See our short video for more tips.

Basic beginnings

Regardless of the assignment, department, or instructor, adopting these two habits will serve you well :

• Read the assignment carefully as soon as you receive it. Do not put this task off—reading the assignment at the beginning will save you time, stress, and problems later. An assignment can look pretty straightforward at first, particularly if the instructor has provided lots of information. That does not mean it will not take time and effort to complete; you may even have to learn a new skill to complete the assignment.
• Ask the instructor about anything you do not understand. Do not hesitate to approach your instructor. Instructors would prefer to set you straight before you hand the paper in. That’s also when you will find their feedback most useful.

Assignment formats

Many assignments follow a basic format. Assignments often begin with an overview of the topic, include a central verb or verbs that describe the task, and offer some additional suggestions, questions, or prompts to get you started.

An Overview of Some Kind

The instructor might set the stage with some general discussion of the subject of the assignment, introduce the topic, or remind you of something pertinent that you have discussed in class. For example:

“Throughout history, gerbils have played a key role in politics,” or “In the last few weeks of class, we have focused on the evening wear of the housefly …”

The Task of the Assignment

Pay attention; this part tells you what to do when you write the paper. Look for the key verb or verbs in the sentence. Words like analyze, summarize, or compare direct you to think about your topic in a certain way. Also pay attention to words such as how, what, when, where, and why; these words guide your attention toward specific information. (See the section in this handout titled “Key Terms” for more information.)

“Analyze the effect that gerbils had on the Russian Revolution”, or “Suggest an interpretation of housefly undergarments that differs from Darwin’s.”

Additional Material to Think about

Here you will find some questions to use as springboards as you begin to think about the topic. Instructors usually include these questions as suggestions rather than requirements. Do not feel compelled to answer every question unless the instructor asks you to do so. Pay attention to the order of the questions. Sometimes they suggest the thinking process your instructor imagines you will need to follow to begin thinking about the topic.

“You may wish to consider the differing views held by Communist gerbils vs. Monarchist gerbils, or Can there be such a thing as ‘the housefly garment industry’ or is it just a home-based craft?”

These are the instructor’s comments about writing expectations:

“Be concise”, “Write effectively”, or “Argue furiously.”

Technical Details

These instructions usually indicate format rules or guidelines.

“Your paper must be typed in Palatino font on gray paper and must not exceed 600 pages. It is due on the anniversary of Mao Tse-tung’s death.”

The assignment’s parts may not appear in exactly this order, and each part may be very long or really short. Nonetheless, being aware of this standard pattern can help you understand what your instructor wants you to do.

Interpreting the assignment

Ask yourself a few basic questions as you read and jot down the answers on the assignment sheet:

Why did your instructor ask you to do this particular task?

Who is your audience.

• What kind of evidence do you need to support your ideas?

What kind of writing style is acceptable?

• What are the absolute rules of the paper?

Try to look at the question from the point of view of the instructor. Recognize that your instructor has a reason for giving you this assignment and for giving it to you at a particular point in the semester. In every assignment, the instructor has a challenge for you. This challenge could be anything from demonstrating an ability to think clearly to demonstrating an ability to use the library. See the assignment not as a vague suggestion of what to do but as an opportunity to show that you can handle the course material as directed. Paper assignments give you more than a topic to discuss—they ask you to do something with the topic. Keep reminding yourself of that. Be careful to avoid the other extreme as well: do not read more into the assignment than what is there.

Of course, your instructor has given you an assignment so that they will be able to assess your understanding of the course material and give you an appropriate grade. But there is more to it than that. Your instructor has tried to design a learning experience of some kind. Your instructor wants you to think about something in a particular way for a particular reason. If you read the course description at the beginning of your syllabus, review the assigned readings, and consider the assignment itself, you may begin to see the plan, purpose, or approach to the subject matter that your instructor has created for you. If you still aren’t sure of the assignment’s goals, try asking the instructor. For help with this, see our handout on getting feedback .

Given your instructor’s efforts, it helps to answer the question: What is my purpose in completing this assignment? Is it to gather research from a variety of outside sources and present a coherent picture? Is it to take material I have been learning in class and apply it to a new situation? Is it to prove a point one way or another? Key words from the assignment can help you figure this out. Look for key terms in the form of active verbs that tell you what to do.

Key Terms: Finding Those Active Verbs

Here are some common key words and definitions to help you think about assignment terms:

Information words Ask you to demonstrate what you know about the subject, such as who, what, when, where, how, and why.

• define —give the subject’s meaning (according to someone or something). Sometimes you have to give more than one view on the subject’s meaning
• describe —provide details about the subject by answering question words (such as who, what, when, where, how, and why); you might also give details related to the five senses (what you see, hear, feel, taste, and smell)
• explain —give reasons why or examples of how something happened
• illustrate —give descriptive examples of the subject and show how each is connected with the subject
• summarize —briefly list the important ideas you learned about the subject
• trace —outline how something has changed or developed from an earlier time to its current form
• research —gather material from outside sources about the subject, often with the implication or requirement that you will analyze what you have found

Relation words Ask you to demonstrate how things are connected.

• compare —show how two or more things are similar (and, sometimes, different)
• contrast —show how two or more things are dissimilar
• apply —use details that you’ve been given to demonstrate how an idea, theory, or concept works in a particular situation
• cause —show how one event or series of events made something else happen
• relate —show or describe the connections between things

Interpretation words Ask you to defend ideas of your own about the subject. Do not see these words as requesting opinion alone (unless the assignment specifically says so), but as requiring opinion that is supported by concrete evidence. Remember examples, principles, definitions, or concepts from class or research and use them in your interpretation.

• assess —summarize your opinion of the subject and measure it against something
• prove, justify —give reasons or examples to demonstrate how or why something is the truth
• evaluate, respond —state your opinion of the subject as good, bad, or some combination of the two, with examples and reasons
• support —give reasons or evidence for something you believe (be sure to state clearly what it is that you believe)
• synthesize —put two or more things together that have not been put together in class or in your readings before; do not just summarize one and then the other and say that they are similar or different—you must provide a reason for putting them together that runs all the way through the paper
• analyze —determine how individual parts create or relate to the whole, figure out how something works, what it might mean, or why it is important
• argue —take a side and defend it with evidence against the other side

More Clues to Your Purpose As you read the assignment, think about what the teacher does in class:

• What kinds of textbooks or coursepack did your instructor choose for the course—ones that provide background information, explain theories or perspectives, or argue a point of view?
• In lecture, does your instructor ask your opinion, try to prove their point of view, or use keywords that show up again in the assignment?
• What kinds of assignments are typical in this discipline? Social science classes often expect more research. Humanities classes thrive on interpretation and analysis.
• How do the assignments, readings, and lectures work together in the course? Instructors spend time designing courses, sometimes even arguing with their peers about the most effective course materials. Figuring out the overall design to the course will help you understand what each assignment is meant to achieve.

Now, what about your reader? Most undergraduates think of their audience as the instructor. True, your instructor is a good person to keep in mind as you write. But for the purposes of a good paper, think of your audience as someone like your roommate: smart enough to understand a clear, logical argument, but not someone who already knows exactly what is going on in your particular paper. Remember, even if the instructor knows everything there is to know about your paper topic, they still have to read your paper and assess your understanding. In other words, teach the material to your reader.

Aiming a paper at your audience happens in two ways: you make decisions about the tone and the level of information you want to convey.

• Tone means the “voice” of your paper. Should you be chatty, formal, or objective? Usually you will find some happy medium—you do not want to alienate your reader by sounding condescending or superior, but you do not want to, um, like, totally wig on the man, you know? Eschew ostentatious erudition: some students think the way to sound academic is to use big words. Be careful—you can sound ridiculous, especially if you use the wrong big words.
• The level of information you use depends on who you think your audience is. If you imagine your audience as your instructor and they already know everything you have to say, you may find yourself leaving out key information that can cause your argument to be unconvincing and illogical. But you do not have to explain every single word or issue. If you are telling your roommate what happened on your favorite science fiction TV show last night, you do not say, “First a dark-haired white man of average height, wearing a suit and carrying a flashlight, walked into the room. Then a purple alien with fifteen arms and at least three eyes turned around. Then the man smiled slightly. In the background, you could hear a clock ticking. The room was fairly dark and had at least two windows that I saw.” You also do not say, “This guy found some aliens. The end.” Find some balance of useful details that support your main point.

You’ll find a much more detailed discussion of these concepts in our handout on audience .

The Grim Truth

With a few exceptions (including some lab and ethnography reports), you are probably being asked to make an argument. You must convince your audience. It is easy to forget this aim when you are researching and writing; as you become involved in your subject matter, you may become enmeshed in the details and focus on learning or simply telling the information you have found. You need to do more than just repeat what you have read. Your writing should have a point, and you should be able to say it in a sentence. Sometimes instructors call this sentence a “thesis” or a “claim.”

So, if your instructor tells you to write about some aspect of oral hygiene, you do not want to just list: “First, you brush your teeth with a soft brush and some peanut butter. Then, you floss with unwaxed, bologna-flavored string. Finally, gargle with bourbon.” Instead, you could say, “Of all the oral cleaning methods, sandblasting removes the most plaque. Therefore it should be recommended by the American Dental Association.” Or, “From an aesthetic perspective, moldy teeth can be quite charming. However, their joys are short-lived.”

Convincing the reader of your argument is the goal of academic writing. It doesn’t have to say “argument” anywhere in the assignment for you to need one. Look at the assignment and think about what kind of argument you could make about it instead of just seeing it as a checklist of information you have to present. For help with understanding the role of argument in academic writing, see our handout on argument .

What kind of evidence do you need?

There are many kinds of evidence, and what type of evidence will work for your assignment can depend on several factors–the discipline, the parameters of the assignment, and your instructor’s preference. Should you use statistics? Historical examples? Do you need to conduct your own experiment? Can you rely on personal experience? See our handout on evidence for suggestions on how to use evidence appropriately.

Make sure you are clear about this part of the assignment, because your use of evidence will be crucial in writing a successful paper. You are not just learning how to argue; you are learning how to argue with specific types of materials and ideas. Ask your instructor what counts as acceptable evidence. You can also ask a librarian for help. No matter what kind of evidence you use, be sure to cite it correctly—see the UNC Libraries citation tutorial .

You cannot always tell from the assignment just what sort of writing style your instructor expects. The instructor may be really laid back in class but still expect you to sound formal in writing. Or the instructor may be fairly formal in class and ask you to write a reflection paper where you need to use “I” and speak from your own experience.

Try to avoid false associations of a particular field with a style (“art historians like wacky creativity,” or “political scientists are boring and just give facts”) and look instead to the types of readings you have been given in class. No one expects you to write like Plato—just use the readings as a guide for what is standard or preferable to your instructor. When in doubt, ask your instructor about the level of formality they expect.

No matter what field you are writing for or what facts you are including, if you do not write so that your reader can understand your main idea, you have wasted your time. So make clarity your main goal. For specific help with style, see our handout on style .

Technical details about the assignment

The technical information you are given in an assignment always seems like the easy part. This section can actually give you lots of little hints about approaching the task. Find out if elements such as page length and citation format (see the UNC Libraries citation tutorial ) are negotiable. Some professors do not have strong preferences as long as you are consistent and fully answer the assignment. Some professors are very specific and will deduct big points for deviations.

Usually, the page length tells you something important: The instructor thinks the size of the paper is appropriate to the assignment’s parameters. In plain English, your instructor is telling you how many pages it should take for you to answer the question as fully as you are expected to. So if an assignment is two pages long, you cannot pad your paper with examples or reword your main idea several times. Hit your one point early, defend it with the clearest example, and finish quickly. If an assignment is ten pages long, you can be more complex in your main points and examples—and if you can only produce five pages for that assignment, you need to see someone for help—as soon as possible.

Tricks that don’t work

Your instructors are not fooled when you:

• spend more time on the cover page than the essay —graphics, cool binders, and cute titles are no replacement for a well-written paper.
• use huge fonts, wide margins, or extra spacing to pad the page length —these tricks are immediately obvious to the eye. Most instructors use the same word processor you do. They know what’s possible. Such tactics are especially damning when the instructor has a stack of 60 papers to grade and yours is the only one that low-flying airplane pilots could read.
• use a paper from another class that covered “sort of similar” material . Again, the instructor has a particular task for you to fulfill in the assignment that usually relates to course material and lectures. Your other paper may not cover this material, and turning in the same paper for more than one course may constitute an Honor Code violation . Ask the instructor—it can’t hurt.
• get all wacky and “creative” before you answer the question . Showing that you are able to think beyond the boundaries of a simple assignment can be good, but you must do what the assignment calls for first. Again, check with your instructor. A humorous tone can be refreshing for someone grading a stack of papers, but it will not get you a good grade if you have not fulfilled the task.

Critical reading of assignments leads to skills in other types of reading and writing. If you get good at figuring out what the real goals of assignments are, you are going to be better at understanding the goals of all of your classes and fields of study.

You may reproduce it for non-commercial use if you use the entire handout and attribute the source: The Writing Center, University of North Carolina at Chapel Hill

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How to Finish Assignments When You Can’t

Crunch time is coming, deadlines need to be met, essays need to be submitted, and tests should be studied for. As a student who’s waiting for the end of crunch time, you’re looking for all the right ways to cut corners while being ultra efficient with your time and energy. But sometimes racing the clock you’ll come to a realization that this mountain of a task is insurmountable and it seems almost impossible to accomplish. But at this low point is exactly where you shouldn’t settle with an incomplete assignment or missing work. There are workarounds and “life hacks” that can help pull you out of this sticky situation.

Homework and education are very important, so finishing your assignments should be something that’s on every student’s mind. Here’s some ideas to get you started on your path to getting your assignments finished:

Ask for an Extension

Lots of students find themselves in this awful situation that seems impossible to do. Even if it is your fault for being a bad student or lazy, it’s worth a try to confront your professor or teacher and ask for an extension – as long as you actually complete it. Teachers and professors understand that the point of homework isn’t to give you something to do, rather train you and give you extra practice on materials you learn in class. Just know that it’s not their responsibility to give you an extension and they are not obligated to give you points for your late or missing assignments. But do them anyway – and have your teacher check your work so they know you’re good for the work even though it’s late. 

Ask for Help from Classmates

Your classmates are a good resource for you to help you finish your assignments, late or on time. They may even just give you answers – as long as you are polite about it and aren’t pressuring them to do so. They are helping you when they aren’t required to, and they’ll be more inclined if you are also reliable. The worst position to be in is to be the student who helps others but doesn’t receive help. Help could even be in the form of understanding the assignments and learning from them, kind of a tutoring situation. But again, it’s important that your classmates aren’t obligated to help you, so be grateful for any help you receive. 

Prevent This Happening in the Future

We don’t want you to constantly be stuck in this seemingly impossible situation – so we urge you to think about your assignments carefully – so it doesn’t happen again. This means several things:

• Keep Organized – understand when your assignments are due, and know how much time you have left so you can plan around it. It’s worth noting that this will also help you plan your lifestyle a bit better, so its a great thing to do
• Give Yourself Time – saving things for last minute is a surefire way to shoot yourself in the foot. Don’t do that. Instead, if they give you an assignment to do for the next lesson or the next day – set time aside after school to do it.
• Don’t Procrastinate – saying that you’ll do it later is the downfall of many missed assignments. You may forget about it or something may come up that will prevent you from doing your assignments on time. Get it done sooner rather than later

Use Your Resources

When we say “resources” we mean tutors, teacher’s assistants, and even the world wide web to help you complete your assignments when you’re unable to. Don’t make it a habit, but there are websites like Assignment Expert that are here to help you do exactly that: finish your homework. Note that schools and universities have their own rules for these types of resources, so use with caution. There are also websites that may have guides or flash cards that can help you in most of your subjects. If you do use them, they can be quite helpful to get you out of this situation. 

Prioritize Your Assignments

If you’ve got a ton of assignments to finish – and only a limited amount of time – its good to prioritize them in an order of importance – which classes do you need to complete them today – ones with very lenient teachers or professors – and ones that are low priority because you’re allowed to miss this one assignment. Having that done, your experience with finishing your assignments will go over much smoother and less stressful. 

Motivate Yourself

There’s a reason why you’re feeling stressed in this crunch time, you’re trying to accomplish something. Whether its to improve your grade or pass class, you still have motivation to do it. If you didn’t have any motivation, you wouldn’t be this stressed to read this article on the internet. But keep in mind your end goals so you’ll have the time and energy to spend on it. Complaining about not having enough time, isn’t going to give you more time.

Figure Out Your Problems

If you’ve procrastinated and put off your assignments, there must be a good reason, right? A good reason or not – you should reevaluate the things you’re doing in your life that put you in this position. If it can be helped, avoid these kinds of situations. Education is important and you should treat it as such. 

Once you get a handle on your situation, you can breathe a sigh of relief. Managing your time isn’t easy, so once its done you can relax a bit before your next deadline. 

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How to Finish Your Homework

Last Updated: July 11, 2024 Fact Checked

This article was co-authored by Emily Listmann, MA . Emily Listmann is a Private Tutor and Life Coach in Santa Cruz, California. In 2018, she founded Mindful & Well, a natural healing and wellness coaching service. She has worked as a Social Studies Teacher, Curriculum Coordinator, and an SAT Prep Teacher. She received her MA in Education from the Stanford Graduate School of Education in 2014. Emily also received her Wellness Coach Certificate from Cornell University and completed the Mindfulness Training by Mindful Schools. There are 16 references cited in this article, which can be found at the bottom of the page. This article has been fact-checked, ensuring the accuracy of any cited facts and confirming the authority of its sources. This article has been viewed 282,921 times.

While studying can differ for different age groups, many of the things that get in the way are the same. Whether it's your environment or time management skills, it easy for things to discourage you from finishing your homework. With a little organization and help, your homework can become approachable.

Managing Your Time

• For instance, try setting aside a time you know you can work well such as an hour or 2 before dinner, or if you're a night owl, after dinner.

• Work in hour blocks, with 50 minutes spent studying and 10 minutes spent taking a break.
• It can also be helpful to move around when you are taking your break, especially if you are working at a screen. Go for a walk outside to get your blood circulating and enjoy some fresh air.
• You might also want to eat a healthy snack on your break to improve your focus. Avoid junk food and choose something like a handful of nuts, a piece of fruit, veggies, or a small portion of cottage cheese.

• Identify which assignments are worth the most points for each class. Most likely these will take the longest to complete. [5] X Research source
• Consider how long you have to do each project, and if possible, see when the assignment is introduced. Oftentimes, primary and secondary school classes do not have syllabi, so it might be harder to plan out an entire term, but if you are in college, you will most likely have a syllabus with at least a partial course schedule. Knowing how long you have to complete an assignment will help you prioritize which assignments to do first. You can also ask the teacher how long you have to complete an assignment. [6] X Research source

• Use highlighters or stickers to mark which assignments are most important.
• If you're using an online or mobile schedule, create alerts or notifications for the projects and any time-sensitive steps for those projects.

• Don't let a big project overshadow the smaller assignments you need to complete!

• Assignment outlines can help you visualize the necessary tasks to get the assignment done.

Creating a Productive Work Environment

• A desk or table would be a better location than a couch or a bed.

• Turn your phone off or on silent (not vibrate). It might be best to put the phone out of sight, or in another room while you work, as the temptation to text or get on social media can be as much of a distraction as actually using social media.
• Use an app that blocks social media. There are plenty of applications out there that can help block social media and other distracting sites (such as shopping or gaming sites). [10] X Trustworthy Source Pew Research Center Nonpartisan thinktank conducting research and providing information on public opinion, demographic trends, and social trends Go to source

• Use a white noise app to block out noise.
• Use earplugs or noise-blocking earmuffs. [12] X Research source
• Work in a quiet place, such as a library or a home office, if you have one.
• Avoid listening to music while studying. Studies have shown that although listening to music while studying lowers overall performance, this does not affect everyone equally. [13] X Research source However listening to music before studying has been shown to improve performance on cognitive tasks. [14] X Research source

Using Your Resources

• If you're too afraid to ask a teacher during class, see if you can stay behind to ask your questions.

• First, contact your school to see if there are any after-school tutoring programs. While not all primary and secondary schools offer tutoring, a vast majority of universities do. If your school does not offer tutoring, they may know of other resources for you to contact.
• Then, contact your library to see if they offer any tutoring. [18] X Research source
• In some areas, there may also be free community tutoring programs. Contact your local community center for more information.
• There are plenty of private tutors out there as well, but they can be costly (ranging from $20 to $100 an hour). [19] X Research source You can find tutors online through a number of websites, such as Craigslist or Angie's list.

• If you need to work at a library after school, ask your parents or search the web to find your local library.

Supercharge Your Studying with this Expert Series

Community Q&A

Reader Videos

• Don't feel too stressed or you'll be doing less work than you actually can. Thanks Helpful 7 Not Helpful 3
• Make sure you’re getting enough sleep. Thanks Helpful 5 Not Helpful 3
• Maintain a healthy diet. Thanks Helpful 5 Not Helpful 3

• Recommended time doing homework varies by age. The National PTA recommends about 10 minutes per grade level per night (30 minutes a night for the third grade). Thanks Helpful 9 Not Helpful 0
• Some people may need additional help in order to focus on their homework and finish it. If you are struggling in school, ask your parents or teachers about what resources may be available, and seek out professional help or ask your parents to do so, if necessary. Thanks Helpful 29 Not Helpful 9
• If you are under the age of thirteen, you may need to obtain your parents’ permission before downloading any computer applications. Thanks Helpful 30 Not Helpful 13

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• ↑ https://kidshealth.org/en/teens/homework.html
• ↑ https://www.takingcharge.csh.umn.edu/power-habit-charles-duhigg
• ↑ https://www.edutopia.org/article/research-tested-benefits-breaks/
• ↑ https://www.wma.us/about/titan-blog/post/~board/titan-blog/post/how-to-prioritize-school-assignments-and-homework
• ↑ https://jhsap.org/self_help_resources/school-life_balance//
• ↑ https://lsc.cornell.edu/how-to-study/studying-for-and-taking-exams/guidelines-for-creating-a-study-schedule/
• ↑ https://success.oregonstate.edu/learning/concentration
• ↑ https://www.pewresearch.org/internet/2020/07/28/parenting-children-in-the-age-of-screens/
• ↑ https://kidshealth.org/en/teens/homework.html/
• ↑ https://absn.northeastern.edu/blog/8-things-to-keep-in-your-at-home-study-space/
• ↑ https://scholar.utc.edu/theses/171/
• ↑ https://onlinelibrary.wiley.com/doi/abs/10.1002/acp.1731
• ↑ https://kidshealth.org/en/teens/talk-to-parents.html
• ↑ https://rdw.rowan.edu/cgi/viewcontent.cgi?article=2412&context=etd
• ↑ https://blogs.chapman.edu/scst/2016/02/09/what-tutoring-is-and-what-tutoring-is-not/
• ↑ https://undergrad.stanford.edu/tutoring-support

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Special Assignment: A Pound of Cure phased

I cannot complete the Special Assignment as I did not complete the other quests in the area on my alt. All I get are two Nerubian burrows that only spawn every few minutes if I fly out and back into the zone, and the mob gives me 4% completion.

I cannot go back and complete the quests in the area to unphase myself because the Special Assignment prevents me from doing so (or it looks like it because when I picked them up, no mobs were visible to me).

I’m running into the same issue. It’s making this world quest take AGES

Same issue.

Same issue can’t complete

same thing…as soon as I enter the WQ area, I get a popup with the special action button, and then everything (even the nearby skyriding glyph!) disappears. no mobs, hardly any buddings. I thought maybe i needed to complete other quests in the area first (with faerin- the all good things storyline) but there’s no way to complete those either. all i can see is the special assignment endboss in the cave

edit: i was able to kill the endboss …i had to leave the area and come back several times, and kill the endboss twice to get quest to complete

This is also bugged for me.

I am having the same issue. I enter the area, the special action button pops up and everything disappears.

Same issue although this is my main and the prerequisite quests should be completed, I also tried to join a party but when I approached them the enemies and my party disappeared.

I found and could kill the boss, but everything else phases out as I enter the area

I had this same issue. As it turns out, I had two campaign quests that had to be completed just north of the Special Assignment: A Pound of Cure world quest. Once I completed those campaign quests, I could see all of the spawns for the world quest.

Sentence examples for completed all assignments from inspiring English sources

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I will admit that I didn't do all of the readings, and yes, I may have missed a couple of lectures throughout the year, but I completed all assignments , followed the guidelines presented to me and understood the consequences of disengagement, without expecting my lecturers to chase after me like I was back in school.

The pure online versions can amass hundreds of thousands of students who complete all assignments at their own pace, aided by their peers and voluntary TAs that monitor message boards for questions.

To avoid this error, make vague goals more specific: "Never be the first to leave the office at the end of the day," " Complete all assignments on time," or "Ask for more responsibilities".

If you've been anywhere close to my shoes, you know the exact mold I'm talking about: the mold that sits calmly in desks for hours on end, doesn't chew on pencils and can complete all assignments in a timely basis with enough energy left to play appropriately and animatedly with their peers.

We obtained a varied number of participant responses for each assessment measure, which was a result of students not completing all assignments , dropping the course, or not completing the informed consent to participate in this research study.

For example if you had an essay, a chapter of reading, and math homework to complete, set specific time span for each assignment and a time you would like to complete all assignments by.

Twenty-nine parti completed o m p l e t e d all three assignments , 22 completed two of the assignments and 33 completed only one assignment.> -wrap-foot> *Agincourt, Digkale, Africa Centre, Ifakara, Rufiji, Magu, Nairobi, Kilifi, Kisumu, Mbita, Navrongo, Dodowa, Kintampo.

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Easily distribute, analyze, and grade student work with assignments for your lms.

Assignments is an application for your learning management system (LMS). It helps educators save time grading and guides students to turn in their best work with originality reports — all through the collaborative power of Google Workspace for Education.

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Save time distributing and grading classwork

Distribute personalized copies of Google Drive templates and worksheets to students

Grade consistently and transparently with rubrics integrated into student work

Add rich feedback faster using the customizable comment bank

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Compare student work against hundreds of billions of web pages and over 40 million books with originality reports

Make student-to-student comparisons on your domain-owned repository of past submissions when you sign up for the Teaching and Learning Upgrade or Google Workspace for Education Plus

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View and navigate your assignments (student)

View both upcoming and completed assignments by class, or view them across all your classes. Selecting an assignment will allow you to view its details, turn it in, or view feedback and scores. You can also view your current grades by class.

View and sort assignments within one class

Navigate to a class team, then select Assignments .

Tip:  Use your search bar to search for an assignment by keyword.

Upcoming assignments

The Upcoming  tab will show all upcoming assignment you have not done yet, sorted by order of due date. The Past Due tab will show all Past Due assignment not completed yet. Sorted by today and older 

Late assignments will include a Past due warning.

Select an assignment to view details, attach resources, and turn it in.

Upcoming assignment status

Assignment title and due date —Before the due date. You haven’t turned in work yet.

Past due —You haven’t turned your assignment in yet and it’s past the due date. This will only appear if your educator is accepting late turn-ins.

View turned in and returned assignments

Completed assignment status

Open a completed assignment to view more details on its status.

View grades in one class

Here you'll see all your assignments listed with the nearest due date at the top. View your status on each assignment as well as points you've received on graded work. Assignments without points will show as Returned after your educator has reviewed them.

Average Grade

If your class has enabled it, you can also see the Average Grade for this class and View Details to see your trend for your assignments.

View assignments across classes

To view assignments across all your classes, select Assignments from your app bar. Select an assignment to open it or turn in work. 

Select Upcoming to see any upcoming assignment across all of your classes.

Select Past Due to see any past due assignment across all of your classes.

Select  Completed to see work that you have completed across your classes.

Turn in assignment

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Turning It In Should Be the Easy Part of Homework, Right?

Even when they complete their homework, students with adhd don’t always remember to turn in assignments on time — or at all. help your kid get credit for all her hard work by setting up these fool-proof organization systems at school and home..

The problem: The student with attention deficit disorder (ADHD or ADD) consistently neglects turning in homework or long-term projects, even though she claims to have completed the work.

The reason: Children with ADHD  have difficulty keeping track of bits of information and paperwork. This problem is likely related to underactive frontal lobes — the area of the brain that controls memory and processing. It’s because of this difference in brain activity that children with ADHD have a hard time focusing on more than one thing at a time.

The obstacles: Children with ADHD often want to complete their work and turn it in on time, but often lack the organizational skills or the memory capacity of other youngsters their age. These students may forget something that just happened as their focus shifts from one task to another or from one class to another. When completing an assignment, for example, students have to work their way through many tasks — including listening to and recording what needs to be done, doing the assignment, and turning it in. It’s very easy for children with ADHD to get interrupted along the way and forget where they are in the process.

Parents and teachers will often find this ADHD behavior puzzling because we assume that, if someone can do something one day, they should have the skill to do it the next day. But mental disorganization causes these children to be inconsistent, leading adults to believe the lapse is intentional. When teachers respond by giving zeroes or bad grades, it only discourages the child and doesn’t solve the problem.

Solutions in the Classroom

Children with ADHD need a high degree of supervision and structure in the classroom. A monitoring system that provides students with cues and reminders can help.

[ Free Parenting Resource: Solve Your Child’s Homework Problems ]

• Provide copies of assignments. Give students written copies of homework assignments whenever possible. This will ensure they have the complete assignment.
• Have parents sign off. Create a homework assignment sheet that must be initialed by both the parent and teacher for oversight and support.
• Break up big assignments. For long-term assignments, plan to track the child’s progress at different points in the process rather than only at the end.
• Create a homework folder. Designate a folder that your child keeps in his binder to help him remember to bring finished homework back to school. Use it as a receptacle for all assignments once they are finished.
• Give feedback. Correct and return the child’s homework as soon as possible. Corrections should be positive and instructive.
• Discuss accommodations. Talk to the child and parent about the accommodations and supports they think might help. No one plan is effective for all students.

[ Free Webinar Replay: Stress-Free Homework: Tips, Tools, and Solutions to Lower the Household Stress Level ]

Solutions at Home

Children with ADHD need parents to help them set up a system to get from the beginning of a project to the end.

• Organize tasks. Help your child create a checklist of required tasks to help her keep track of where she is in the assignment process. Make copies of the checklist to keep in her binder and post in her room.
• Label and color-code books, binders, and folders. All subjects should use the same color to keep paperwork organized .
• Establish routines. Set up a routine specifically for getting assignments back to the teacher (for example, as soon as it’s finished, it goes into a folder next to the front door).
• Don’t let your child procrastinate. He will likely need your help to get started on a task and see it through.

Some children desire more independence. Tell yours that she can earn the right to monitor her own work after demonstrating success for a few weeks.

[ 9 Secrets to a Super Effective School Planner ]

Homework & Studying: Read These Next

9 Things I Wish the World Knew About My Students’ ADHD

A Teacher’s Guide to NVLD: How to Support Students with Nonverbal Learning Disability

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Hallowfall World Quests Guide

• Author: Luxrah
• Date: September 10, 2024
• Updated: September 11, 2024
• Expansion: World of Warcraft

Completing the main storyline in Khaz Algar and reaching level 80 unlocks World Quests for your character on the continent. These quests are special time-limited activities that offer a variety of rewards as well as some reputation with the Hallowfall Arathi for your Warband . In this guide, we’ll tell you where to go and what you need to do to complete each of these quests.

First, here are some other special activities and events that you can find in Hallowfall :

• Spreading the Light World Event
• Shurrai, Atrocity of the Undersea World Boss
• Bountiful Delves

World Quests

This section lists the standard world quests in Hallowfall that do not have a special quest type (PvP, pet battle, Skyrider racing, or Special Assignment).

Aquacalypse

• 12 Kobyss attackers slain

Kill kobyss around the two northern islands that make up Velhan’s Claim. Mobs that count for the quest are Bristlespine , Droopfin , Kobyss Fighter , Kobyss Trickster , Murkfin Depthstalker , Murkfin Ravager , Murkfin Sciomancer , and Sharpfang .

Beledar’s Blessing

• Climbing Gear acquired
• Find a handhold on the cliff
• 7 Collect Radiant Clusters

Click on the Climbing Gear at the bottom of the rockface to equip it. Then click on the Handholds to start climbing. Make use of the special abilities to maintain your grip and navigate the cliff. Click on the Radiant Clusters you encounter along the way to loot them and complete the quest.

Burrow Burial

• 5 Nerubian Burrow Destroyed

All you need to do is click on the Nerubian Burrows on the ground to collapse them.

Documenting: Field Manual Edition

• Ride the Cataloger’s Disc
• Take Pictures of Wildlife

You’ll need to mount the Cataloger’s Disc down the cliff from Light’s Redoubt (39.9, 74.7). Then you’ll be taking pictures of wildlife to fill the progress bar.  Common  pictures will give you 3% progress each,  Rare  pictures are worth 5%,  Epic  pictures give 10%, and a  Legendary  picture gives 20%. To get a Legendary shot, keep an eye out for Puppetmaster (38.8, 83.0).

Feline Frenzy

• Ride the Imperial Lynx
• 100 Scare Locals

Cat zoomies! Mount the Imperial Lynx at the stable on the south side of Mereldar (42.0, 58.0). Ride it around the town and run through the piles of Lynx Treats along the way for a speed boost, but avoid the Catnip bushes as they will stun your lynx.

Igniting the Fire Within

• 1 Torch lit
• 6 Arathi groups rallied

Interact with the Torch that is resting near Faerin at Sina’s Yearning (55.2, 32.7). Once it’s lit, look for groups of Arathi who are fighting nearby. Get close to them and the Rally ability will appear on your screen. Use it to rally the Arathi forces.

Into Shadows

• Talk to Venrie to board the skiff
• 20 Keening Shadows slain

Board the skiff at Dunelle’s Kindness by speaking with Venrie Flitter (67.4, 44.4). Use the cannons to fire at Keening Shadows to complete the quest.

Kobyss Kibosh

• Assist the Arathi in driving back the kobyss

To fill your progress bar, you’ll need to either heal Arathi Stalwart s on the Veneration Grounds or kill kobyss in the same area. Enemies who count toward the quest include Darkwater Tidecrusher , Grimslice , Ragefin Carver , Ragefin Executioner , Ragefin Necromancer , and Ragefin Shadowcaster . Each enemy killed or friendly NPC healed counts for about 7% quest progress.

Mired in Shadow

• Clear the Shadowmire

Exterminate the bugs in the Shadowmire (a cavern east of Dunelle’s Kindness). Parasiting Wasps are worth about 3% quest progress, Bloatrot Stingers and Fungal Infestors are worth about about 8%, and Fallowbarb and Sloshmuck are worth about 14% each.

Pool Cleaner

• 15 Kobyss slain

IMPORTANT: Do not tell Alyza Bowblaze to go back to the orphanage when she joins you. This dialogue option currently causes a bug where you are phased to a nearly empty version of Hallowfall. If you have done this by mistake, you can find Alyza inside the Orphanage in Mereldar and tell her to join you again.

Defeat any of the Hungering kobyss around The Hungering Pool to complete the quest: Hungering Necromage , Hungering Shimmerfin , and/or Hungering Slicer .

Recovery Job

• Smash Arathi Supply crates and recover Airship Tools

Look for Arathi Crates around Tanir’s Ascent and attack them to break them open. Keep in mind that unlike most interactive world quest objects, these are not personal, meaning that any other player can swoop down and take them and they will disappear until they respawn. When smashed, the crates have a chance to reveal one of two lootable objects: Airship Munitions will give you a special ability, Throw Munitions , while Arathi Supplies will give you the Shipyard Tools you need to complete the quest.

Reserve Rumpus

• 8 Duel Arathi Recruits

Near the Hallowfall Arathi quartermaster’s tent, challenge 8 of the Arathi Reserve NPCs to a duel and defeat them.

Sieging Siege Weapons

• 4 Keg of Black Powder
• 4 Blackpowder Barrel Placed

Interact with Blackpowder Barrels around Tenir’s Ascent to loot 4 Keg of Black Powder . Then place them in the marked locations down the hill to complete the quest.

Spore Ender

• Darkcap Tain slain
• 30 Fragrant Mirespores

You’ll find Darkcap Tain in the south corner of the Stagnant Mire between some waterfalls (60.9, 65.5). Fragrant Mirespores can be looted from creatures throughout the Stagnant Mire, including Cultivated Mireshroom , Mirehat Fungalmancer , Mirehat Sporedancer , Sludgeborn Shambler , and Darkcap Tain himself.

With Great Pyre

• Wield the Gift of Pure Flame
• 6 Hollow Gigantobella slain

In order to “wield” the flame, use the Periapt of Pure Flame that has been added to your bags. Then defeat 6 Hollow Gigantobellas around the Growling Hollow.

Work Hard, Play Hard

• 4 Play with orphan

For this quest, you’ll be playing with the kids at The Orphanage in Mereldar (41.9, 55.3). You can speak to any Arathi Orphan in the area to interact with them and complete an unique mini-game. Any 4 games will count, but you may want to try different ones on your alts or on different days so you can earn the Children’s Entertainer achievement.

• A group of 3 orphans are upstairs inside the building (41.6, 55.6). Tell them who you think is scarier: Kobyss or Nerubians (either answer completes the game).
• Two orphans are running around the yard. Interact with one to tag them and complete the objective.
• A trio of orphans can be found at the playground (42.0, 55.4). Use the four abilities on your bars – Scary Roar , Taunting Flex , Kaiju Chomp , and Scared Monster! – to interact with them and complete the game.
• A lone orphan is under a tree in the yard (42.0, 55.6). Speak with him to begin the game. You’ll be placed on top of the fence and must make your way across the yard without touching the ground. Run along the fence and jump carefully across the gaps to reach the orphan at the other end.
• This is the same as the regular version, but with a slightly different layout that requires a lot more jumping.
• A group of 3 orphans are looking at the targets in the yard (41.9, 55.5). Speak with them, and use the Throw Rock ability to hit one of the targets.
• A lone orphan is standing just outside the building entrance (41.8, 55.3). Speak with him to begin the game. You’ll have a special UI element that shows you how close you are to the hiding child. If the green fills in the lines, you’re getting closer. The child will be very hard to see until you’re almost on top of them, like they are in stealth. Interact with them to complete the game.
• This is the same as the regular version, but the distance indicator won’t work. You’ll have to explore the area and try to find the child on your own.

PvP World Quests

These world quests will not appear on your map unless you have  War Mode  turned on. To enable War Mode, head to a major city (Dornogal, Valdrakken, or your faction capital) and open your talents window. Click on the circle in the lower right corner so that it lights up. There are ways to complete these quests without killing other players, but you must have War Mode on the whole time.

Bells of the Light

• Kill Arathi Trainers or Players

To fill up the progress bar, you’ll either need to kill  players  or defeat Arathi Devout , Arathi Discipline , and/or Arathi Recruit around the Priory of the Sacred Flame. Players count for 14% of your progress bar while Arathi count for 10% each. If you choose to fight enemies on top of the walls, be careful that you stay within the quest area or your kills will not count toward your progress.

Fending off Darkness

• Push back the Kobyss or Kill Players

To fill up the progress bar, you’ll either need to kill  players  or defeat Fathomless kobyss around The Fangs. Players count for 14% of your progress bar. Fathomless Ambusher , Fathomless Necromancer , and Fathomless Warrior count for 10%. Fathomless Scouts count for 8%.

Pet Battle World Quests

These world quests involve winning pet battles against some challenging opponents.

Miniature Army

• Defeat Kyrie in a Pet Battle

Kyrie  is an Expert Pet Trainer near the small lake just south of Lightspark (52.4, 62.8). Her pets are  Flicker ,  Mini Airship , and  Sir Pounce . Flicker is a Flying type pet who is weak to Magic abilities but resistant to Beast abilities. Mini Airship is a Mechanical type pet that is weak to Elemental abilities and resistant to Magic abilities. Sir Pounce is a Beast type and is weak to Mechanical abilities but strong against Humanoids.

The Thing from the Swamp

• Defeat Guttergunk in a Pet Battle

Guttergunk is an Elemental type battle pet who is standing beside the Whispering Pool (61.1, 69.0). It is weak to Aquatic abilities but resistant to Mechanical abilities.

Skyrider Racing World Quests

For these world quests, you’ll be tasked with completing one of the  Skyriding  races that are scattered around the map. To do so, speak with the Bronze Timekeeper at the race location and choose the version of the course you’d like to try. Any version will count as long as you complete the race in time to earn at least Bronze.

Skyrider Racing – Light’s Redoubt Descent

• Complete the race

This Bronze Timekeeper is atop a high stone pillar overlooking Light’s Redoubt (41.4, 67.2).

Skyrider Racing – Mereldar Meander

This  Bronze Timekeeper  is on top of a high stone pillar south of Mereldar (39.0, 61.3).

Skyrider Racing – Stillstone Slalom

This  Bronze Timekeeper  is atop a high hill at Isaec’s Folley (60.4, 26.0).

Skyrider Racing – Tenir’s Traversal

This  Bronze Timekeeper  is on a cliff overlooking the Whispering Pool from Tenir’s Ascent (59.2, 68.9).

Skyrider Racing – Velhan’s Venture

This  Bronze Timekeeper  is on a high hill on the island at the Sunless Strand (54.1, 17.4).

Special Assignment World Quests

These world quests require completing a certain number of other world quests in Hallowfall before they will become available. Until this prerequisite is met, they’ll appear on the map with a lock symbol.

Special Assignment: Lynx Rescue

• Find and befriend a lost lynx
• 4 Hunt Vanishing Nightmares

The lost lynx you’re looking for is Twinkle, who you’ll find stealthed in the Sanguine Grasps near the Aegis Wall (66.9, 63.5). Interact with them and they’ll join you, giving you a 10 minute buff, Summon Twinkle , and a special ability, Crush Windpipe . You must use this ability on Vanishing Nightmares , elite aberrations in the Sanguine Grasps, to prevent them from vanishing once you engage them in combat. Defeat four of these elites to complete the quest.

Special Assignment: Rise of the Colossals

• Kill Colossal beasts

First, kill mobs with Bleak in their name along the western shore of Bleak Sand, the northeasternmost island. Look for Bleak Beak-Carver , Bleak Beastbreaker , Bleak Claw-Eater , Bleak Flesh-Taker , and Bleak Seatamer and loot 3 Bleak Chum from them. Then look for a pool of Frothing Waters and throw the Bleak Chum into it to summon a Colossal mob. Defeat 3 of these Colossals to complete the quest.

Worldsoul Memories World Quests

You won’t be able to see these quests unless you have at least one Radiant Echo in your inventory. Worldsoul Memories are unique world quests that must be started by interacting with a Worldsoul Memory orb at the world quest location. You’ll select the difficulty level you’d like to attempt. Each difficulty grants better rewards and costs more  Radiant Echo es to start. Once the event starts, your goal is to increase the  Worldsoul Memory Score  at the top of your screen by defeating enemies, mining Azerite, and interacting with objects in the area. Each quest also requires defeating a special named enemy. These quests do not award any reputation.

Worldsoul Memory: Descendant of Distant Waters

• Defeat as many hostile visions as possible
• Zin’ghas the Brute slain

Worldsoul Memory: Reign of the Old Gods

• Thystoria slain

About the Author

• Research Article
• Open access
• Published: 10 September 2024

Postcranial anatomy of Besanosaurus leptorhynchus (Reptilia: Ichthyosauria) from the Middle Triassic Besano Formation of Monte San Giorgio (Italy/Switzerland), with implications for reconstructing the swimming styles of Triassic ichthyosaurs

• Gabriele Bindellini   ORCID: orcid.org/0000-0001-6359-3067 1 , 2 ,
• Andrzej S. Wolniewicz 3 , 4 , 5 ,
• Feiko Miedema 6 ,
• Cristiano Dal Sasso 7 &
• Torsten M. Scheyer 8  

Swiss Journal of Palaeontology volume  143 , Article number:  32 ( 2024 ) Cite this article

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Besanosaurus leptorhynchus Dal Sasso & Pinna, 1996 was originally described on the basis of a single complete fossil specimen excavated near Besano (Italy). However, a recent taxonomic revision and re-examination of the cranial osteology allowed for the assignment of five additional specimens to the taxon. Here, we analyse, describe and discuss the postcranial anatomy of Besanosaurus leptorhynchus in detail. The size of the specimens examined herein ranged from slightly more than one meter to eight meters. Overall, several diagnostic character states for this taxon are proposed, demonstrating a mosaic of plesiomorphic and derived features. This is best exemplified by the limbs, which show very rounded elements in the forelimbs, and pedal phalanges with retained rudimentary shafts. We suggest that the widely spaced phalanges in the forefins of Besanosaurus leptorhynchus were embedded in a fibrocartilage-rich connective tissue, like in modern cetaceans. We also review the similarities of Besanosaurus with Pessopteryx and Pessosaurus, allowing us to conclude that Besanosaurus is not a junior synonym of either of the two taxa. Lastly, to test the swimming capabilities of Besanosaurus leptorhynchus , we expanded on a previously published study focussing on reconstructing the swimming styles of ichthyosaurs. Besanosaurus   leptorhynchus was found to possess a peculiar locomotory mode, somewhat intermediate between anguilliform swimmers, such as  Cymbospondylus  and  Utatsusaurus , and some shastasaur-grade (e.g.,  Guizhouichthyosaurus ) and early-diverging euichthyosaurian (e.g.,  Californosaurus ) ichthyosaurs. Based on our results, we furthermore suggest that mixosaurids acquired their characteristic body profile (dorsal fin and forefins that are distinctly enlarged compared to the hindfins) independently and convergently to the one that later appeared in Parvipelvia. Moreover, the different swimming styles inferred for Cymbospondylus, Mixosauridae , and Besanosaurus strengthen the earlier hypothesis of niche partitioning among these three distinct ichthyosaur taxa from the Besano Formation.

Introduction

Cymbospondylids and shastasaurs were important members of Triassic marine ecosystems, representing the earliest medium- to large-bodied ichthyosaurs, ranging in size from about 6 m to more than 20 m (Klein et al., 2020 ; Nicholls & Manabe, 2004 ; Sander et al., 2011 , 2021 , 2024 ). The monophyly of Shastasauridae (recovered by e.g., Huang et al., 2019 ; Ji et al., 2013 , 2016 ; Jiang et al., 2016 ; Motani et al., 2017 ) has been questioned in the past, and the clade has been recovered as paraphyletic by several authors (e.g., Bindellini et al., 2021 ; Maisch & Matzke, 2000 ; Moon, 2019 ; Moon & Stubbs, 2020 ; Sander, 2000 ; Sander et al., 2011 ). In this paper, we consider the clade as paraphyletic and refer to the taxa previously included in Shastasauridae sensu Ji et al. ( 2016 ), i.e., Shastasaurus , Besanosaurus , Guanlingsaurus (junior synonym of Shastasaurus according to some authors; Sander et al., 2011 ; Moon et al., 2019 ), Guizhouichthyosaurus , Shonisaurus , and ‘Callawayia ' wolonggangense as shastasaur-grade ichthyosaurs (sensu Bindellini et al., 2021 ) and provide additional evidence in support to this designation.

Ichthyosaurs are greatly abundant fossil marine reptiles of the Monte San Giorgio UNESCO World Heritage Site (Canton Ticino, Switzerland, and Lombardy, Italy; Fig.  1 ), protected for its Middle Triassic marine fossil palaeobiodiversity (e.g., Rieppel, 2019 ). In the sedimentary succession of Monte San Giorgio, the Besano Formation (dated to the Anisian/Ladinian boundary) was found to be particularly rich in both vertebrate and invertebrate fauna. In this formation, three distinct clades belonging to Ichthyosauria have been recovered: Mixosauridae, Cymbospondylus , and the shastasaur Besanosaurus. The holotype of Besanosaurus leptorhynchus (BES SC 999; Dal Sasso & Pinna, 1996 ) was unearthed in 1993 in the Sasso Caldo quarry near Besano. Since its first description, it was found to show close affinity with shastasaur-grade ichthyosaurs, despite exhibiting several unique characters both in the skull and the postcranial skeleton. However, BES SC 999 was not the only shastasaur recovered from Monte San Giorgio/Besano. Three well-preserved specimens, two medium-sized (PIMUZ T 4376 and PIMUZ T 1895) and a large (PIMUZ T 4847) skeleton, were present in the collections of the Paläontologisches Institut und Museum der Universität Zürich (PIMUZ) since the late 1920s/early 1930s (PIMUZ records). These skeletons were briefly mentioned in 20th-century literature (Brinkmann, 1994 , 1997 ; Cook, 1994 ; Kuhn-Schnyder, 1964 ; McGowan, 1976 ; Sander, 1989 ), and the medium-sized skeleton was seemingly under study in the 1990s (Cook, 1994 ; Dal Sasso & Pinna, 1996 ; Brinkmann, 1997 ), but a comprehensive osteological description was never published.

A Map of the Monte San Giorgio area showing the Middle Triassic carbonate succession, the major paleontological quarries in the area (white circles), and the sites of origin of the specimens described in this paper (yellow rhombuses). B Stratigraphic log of the Besano Formation at the Mirigioli/Punkt 902 outcrop, with the known stratigraphic positions of the specimens marked. The stratigraphic position of PIMUZ T 1895 and GPIT 1793/1 is uncertain, and thus expressed by a range line. Log modified from Brack et al. ( 2005 ); dating of layer 71 from Mundil et al. ( 1996 ); dating of Tc Tuffs (layers 66–68) from Wotzlaw et al. ( 2017 )

In this work, we revise the postcranial anatomy of Besanosaurus leptorhynchus and describe the postcranial skeletons of the above-mentioned shastasaurid specimens from the PIMUZ collections in detail for the first time. Furthermore, we comprehensively compare these specimens with other ichthyosaurs, make inferences on the swimming style of Besanosaurus and other Middle Triassic ichthyosaur taxa, infer the ossification patterns of some parts of the skeleton, and address taxonomic issues related with the Early–Middle Triassic ichthyosaurs Pessopteryx and Pessosaurus from Svalbard.

Geological setting

The Besano Formation (also referred to as Grenzbitumenzone) crops out on Monte San Giorgio (Lombardy, Italy, and Canton Ticino, Switzerland; Fig.  1 ) and is one of the richest and most well-known sites of Middle Triassic marine palaeobiodiversity (e.g., Benton et al., 2013 ; Rieppel, 2019 ). Four different formations form the Middle Triassic carbonate succession of Monte San Giorgio; they were deposited on the western margin of the Neo-Tethys in a carbonate platform sedimentological context (Bernasconi, 1994 ; Etter, 2002 ; Furrer, 1995 ; Röhl et al., 2001 ; Stockar et al., 2012 ). The formations are the San Salvatore Dolomite, the Besano Formation, the San Giorgio Dolomite, and the Meride Limestone (Fig.  1 ). During the Anisian, after the deposition of the Salvatore Dolomite, the development of a 30–130 m deep and approximately 20 km wide basin resulted in the deposition of the Besano Formation (e.g., Bernasconi, 1991 , 1994 ; Bernasconi & Riva, 1993 ; Furrer, 1995 ). It is 5 to 16 m thick and consists of an alternation of black shales and variably laminated, organic-rich dolomitic layers. Subordinate cineritic tuffs were used to date the formation to the Anisian/Ladinian boundary (Brack & Rieber, 1986 , 1993 ; Brack et al., 2005 ; Mundil et al., 1996 ; Wotzlaw et al., 2017 ). The formation is divided into three portions (Röhl et al., 2001 ): the upper and lower portions of the Besano Fm. represent a restricted, shallow, inter-to-subtidal carbonate platform rich in nearshore vertebrates, whereas the middle part is a slightly deeper intraplatform basin, from which a great number of ichthyosaurian and other pelagic vertebrate remains have been recovered (e.g., Bürgin et al., 1989 ; Dal Sasso & Pinna, 1996 ; Brinkmann, 1997 ; Maisch & Matzke, 1998 ; Furrer, 2003 ; Renesto et al., 2020 ; Bindellini et al., 2021 ; Bindellini & Dal Sasso, 2022 ; Miedema et al., 2023 ; Viaretti et al., 2020 , 2023 ). At the Sasso Caldo site near Besano, only the middle and the upper portions of the Besano Formation crop out. Recent biozonation of the Sasso Caldo site (Bindellini, 2022 ; Bindellini et al., 2019 ) allowed a confident correlation of this stratigraphic section with the Swiss localities (Brack & Rieber, 1993 ; Brack et al., 2005 ; Rieber, 1973 ).

The four specimens referred to Besanosaurus leptorhynchus described in this work originate from the middle portion of the Besano Formation and are dated to the N. secedensis Zone. The holotype of Besanosaurus leptorhynchus (BES SC 999) was collected at the Sasso Caldo site from the equivalent of layer 107 of the Besano Formation type section (Bindellini et al., 2021 ; Dal Sasso & Pinna, 1996 ). PIMUZ T 1895 and PIMUZ T 4847 come from the Cava Tre Fontane site. The latter was recovered from layer 116, whereas the exact horizon of origin of the former is unknown. PIMUZ T 4376 comes from the Valle Stelle site and was collected from layer 71 (Bindellini et al., 2021 ; Furrer, 2024 ; Fig.  1 ).

Material and methods

All studied specimens come from the Monte San Giorgio area (Fig.  1 ), where fossils lay in a single bedding plane and are compressed by diagenetic alteration and fossilisation (Figs.  2 and 3 ). Disarticulation is more common in the forefins than in the hindfins, and in the postsacral rather than presacral axial skeleton (BES SC 999, PIMUZ T 4376, PIMUZ T 4847). One specimen, the holotype, BES SC 999, contains foetal and soft tissue remains, whereas the largest specimen, PIMUZ T 4847, contains a large pyritised mineral nodule in the cranial half of the thoracic region, possibly related to visceral soft tissue. All specimens underwent extreme taphonomical compression, and therefore bones are often preserved in a very thin layer, sometimes as thin as a few millimetres. PIMUZ T 4376 represents a partial exception to this rule since some anatomical features are preserved more three-dimensionally in this specimen. The extreme taphonomic compression greatly distorted some of the preserved morphological features, especially in the limbs and girdles, necessitating caution in interpreting the actual anatomy of the specimens (see also the skull description, Bindellini et al., 2021 ).

A Cast of BES SC 999, the holotype of Besanosaurus leptorhynchus and ( B ) interpretative drawing (modified from Dal Sasso & Pinna, 1996 ). Foetal remains are highlighted with green lines. a astragalus, c calcaneum, Cl clavicle, Co coracoid, Fe femur, Fi Fibula, H humerus, i intermedium, Il Ilium, Is Ischium, P pubis, p pisiform, R radius, r radiale, S scapula, T Tibia, U Ulna, u ulnare; 2, 3, and 4, distal carpals and tarsals; II, III, IV, and V, metacarpals and metatarsals. The apostrophe (‘) indicates left elements. Scale bar represents 50 cm

Three additional skeletons referred to Besanosaurus leptorhynchus . A PIMUZ T 4376, the smallest individual, an almost complete specimen with disarticulated tail and missing some of the elements from the fins; B PIMUZ T 1895, a smaller individual missing most of the fins, sacrals and postsacral elements; a portion of the tail of PIMUZ T 1895 is preserved in an additional block (Fig.  5 A); C PIMUZ T 4847, a large adult missing most of the fins, sacrals and postsacral elements. Scale bars represent 50 cm

The studied specimens can be ordered according to increasing body size as follows:

PIMUZ T 4376—the smallest specimen (Figs. 3 , 4 , 6 ). It measures 2.12 m from the tip of the rostrum to the last preserved caudal vertebra (the distalmost caudals are missing).

PIMUZ T 1895—the specimen is incomplete (lacking most of the tail and the limbs, except for the tailbend) but mostly articulated (Figs. 3 , 5 ). The preserved presacral length is around 1.40 m. The preserved elements suggest that the absolute size of this specimen was intermediate between that of PIMUZ T 4376 and BES SC 999.

BES SC 999—the holotype of Besanosaurus leptorhynchus , a pregnant female (Figs. 2 , 4 , 5 , 6 ). It measures 5.07 m from the tip of the rostrum to the last caudal vertebra. The skeleton is virtually complete and exposed in ventral view.

PIMUZ T 4847—the largest specimen described in this work (Figs. 3 , 6 ). It has a presacral length of 3.28 m but lacks most of the postsacral skeleton and most of the limb bones. In life, this individual likely reached a length of about 8 m (Bindellini et al., 2021 ).

In addition, two complete and articulated specimens referred to Mixosaurus cornalianus (BES SC 1000 and BES SC 1001) (Renesto et al., 2020 ) were personally examined during the preparation of this study and used solely for comparative purposes.

X-ray computed tomography (CT) was performed on BES SC 999, the holotype of Besanosaurus leptorhynchus , with a Siemens Somatom Definition Dual Source CT Scanner at the Radiology Department of the Fondazione IRCCS “Cà Granda” Ospedale Maggiore Policlinico di Milano. The best CT imaging was obtained with a bone algorithm on transverse (axial) slices with a voltage of 140 kV, a current of 180–270 mA, and a slice thickness of 0.3 mm (Crasti, 2019 ). Data were exported in DICOM format using eFilm (v. 1.5.3; Merge eFilm, Toronto, ON, Canada). Analysis and post-processing were performed with RadiAnt, 3DimViewer, and Synedra View Personal. Multiplanar reconstructions (MPR) and volume rendering reconstructions (VR) allowed us to inspect the bones hidden from external view by other bones embedded within the matrix, otherwise impossible to study without damaging the fossil.

Photogrammetry was used to better inspect the postcranial anatomy of specimens BES SC 999 and PIMUZ T 4376. Photos of all studied specimens were taken with a Nikon D3500 camera using the RAW file format. Figures included in the manuscript are slightly post-produced versions of these RAW files to enhance highlights and shadows.

To assess the phylogenetic position of Besanosaurus leptorhynchus , a phylogenetic analysis was performed in TNT 1.5 (Goloboff & Catalano, 2016 ). The analysis was based on that presented by Bindellini et al. ( 2021 ), with postcranial character scores for Besanosaurus leptorhynchus updated on the basis of this study.

To investigate the swimming mode of Besanosaurus leptorhynchus , we plotted 27 additional taxa (16 ichthyopterygians and 11 fishes) onto a body shape diagram originally produced by Motani et al. ( 1996 ) (see also Motani, 2005 , 2008 ; Lindgren et al., 2013 ). This procedure allowed for the inclusion of a broader representation of taxa in terms of phylogenetic diversity and swimming styles than the original analysis of Motani et al. ( 1996 ). The “caudal fin H/L ratio” (caudal fluke height divided by fluke length) is plotted on the x-axis and the “fineness ratio” (body height—excluding the dorsal fin—divided by prefluke length) is plotted on the y-axis. The fish taxa included in the analysis represent different swimming modes, likely also exhibited by ichthyopterygians (anguilliform, subcarangiform, carangiform, and thunniform) (McGowan, 1992 ; Motani, 2008 ; Motani et al., 1996 ). We decided to add 10 taxa belonging to Scombridae, to show where extant taxa of thunniform swimmers plot, since this swimming mode was underrepresented in the original analysis of Motani et al. ( 1996 ). Silhouettes of both ichthyosaurs and fishes, along with their sources, as well as the measurements obtained from them, are included in Fig. S6 and Tab. S1. Since the height of the dorsal lobe of the caudal fluke is not known in Californosaurus , Temnodontosaurus , and Eurhinosaurus , we plotted three different possible reconstructions for these genera: one in which the dorsal lobe of the caudal fluke is as reconstructed in Fig. S6, one in which it is 50% the height of the ventral lobe, and one in which it is 25% of the height.

Systematic palaeontology

ICHTHYOPTERYGIA Owen, 1859

ICHTHYOSAURIA Blainville, 1835

MERRIAMOSAURIA Motani, 1999

BESANOSAURUS Dal Sasso & Pinna, 1996

Besanosaurus leptorhynchus Dal Sasso & Pinna, 1996

Type and only species Besanosaurus leptorhynchus Dal Sasso & Pinna, 1996 .

Type specimen Complete, mostly articulated skeleton (Fig.  2 ), listed as BES SC 999 in the catalogue of the MSNM (BES SC is an acronym for the Besano Sasso Caldo quarry) and coded as 20.S288-2.2 in the Inventario Patrimoniale dello Stato (Italian State Heritage Database).

Type locality Sasso Caldo site, Besano, Varese Province, NW Lombardy, N Italy. Geographical coordinates: 45°54′03.7ʺN 8°55′10.6ʺE, elev. 650 m.

Type horizon and distribution Middle portion of the Besano Formation (sensu Bindellini et al., 2019 ), uppermost Anisian ( N. secedensis Zone sensu Brack et al., 2005 ), Middle Triassic.

Referred material PIMUZ T 4376 (complete, mostly articulated skeleton with the best-preserved skull of the taxon; Fig.  3 A), PIMUZ T 1895 (incomplete, mostly articulated skeleton with a well-preserved skull; Fig.  3 B), PIMUZ T 4847 (incomplete, mostly disarticulated skeleton with a disarticulated skull; Fig.  3 C), GPIT 1793/1 (disarticulated skull, the holotype of Mikadocephalus gracilirostris Maisch & Matzke, 1997 ), BES SC 1016 (incomplete, mostly disarticulated skull; the specimen is coded as 20.S288-2.6 in the Inventario Patrimoniale dello Stato (Italian State Heritage Database).

Emended diagnosis Large ichthyosaur (estimated adult body length ~ 8 m) with one possible autapomorphy—a caudoventral exposure of the postorbital in the temporal region—and the following combination of character states: extremely long, slender, and gracile snout; frontal rostrocaudally elongate and relatively flat; frontal participation in the temporal fossa (= anterior terrace; Motani, 1999 ) but not in the temporal fenestra; L-shaped jugal; ‘triangular process’ on the medioventral border of the quadrate; prominent coronoid (preglenoid) process of the surangular, distinctly raised above its dorsal margin; tiny, conical teeth with a coarsely-striated crown surface and deeply striated roots; mesial maxillary teeth set in sockets; distal maxillary teeth set in a groove shorter than half of the rostral ramus of the maxilla; 61 presacral vertebrae, at least two sacral vertebrae, and at least 138 caudal vertebrae; tailbend forming an angle of ~ 30°; wedge-shaped caudal centra located between the 56–60th position in the caudal series, possessing small and rounded articular surfaces for possibly unossified ribs; caudal series comprising 55% of the length of the axial skeleton in adults; rounded humerus; rounded manual phalanges; pedal phalanges retaining reduced shafts in adults; obturator foramen with a sub-oval outline, open in juveniles and almost entirely enclosed within the pubis in adults.

Remarks Several additional specimens at the PIMUZ are potentially referable to Besanosaurus and are treated as aff. Besanosaurus herein. Previously, these specimens were preliminarily identified in the field as Mixosaurus (except PIMUZ T 2027, which was labelled as Shastasauridae indet.) and include: PIMUZ T 188, two isolated paddle elements preserved on the surface of one matrix slab; PIMUZ T 190, isolated and badly preserved paddle elements on two matrix slabs; PIMUZ T 1935, jaw fragments on one slab; PIMUZ T 1973, incomplete skeletal remains on nine (potentially ten if one unnumbered slab is counted as well) matrix slabs; PIMUZ T 2010, skull remains on two slabs; PIMUZ T 2013, large skeletal remains including trunk and paddle remains on three slabs (incl. T 2015, which was identified as a counterslab to one of the two slabs of T 2013); PIMUZ T 2027, vertebral elements (several sectioned histologically) on one slab; PIMUZ T 2141, vertebrae and a girdle element on one slab; PIMUZ T 2144, skull and lower jaw remains; PIMUZ T 2259, jaw remains on two slabs; PIMUZ T 2359, articulated vertebrae with chevron bones on one slab; and PIMUZ T 2759, large jaw fragments on one slab.

Description

Axial skeleton.

We recognise 12 cervical centra, 49 dorsal centra, at least two sacral centra, and at least 138 caudal centra (201 vertebrae in total) in the axial skeleton of the holotype of Besanosaurus leptorhynchus (BES SC 999). The overall count of presacral vertebrae is at least 61. In PIMUZ T 4376, the caudalmost portion of the tail is not preserved, missing about 30 vertebrae from the tip of the tail. The preflexural and postflexural counts are 57 and 81, respectively. Apical wedge-shaped caudal centra are located between the 56–60th position in the caudal series. Cervical, dorsal, and proximal caudal centra are generally subcircular in outline in articular (anterior/posterior) view; mid-caudal centra become ovoid in outline and mediolaterally compressed (Dal Sasso & Pinna, 1996 : fig. 13). All centra are amphicoelous and possess the typical ichthyosaurian hourglass-shaped sagittal cross-section.

Cervical centra —In PIMUZ T 4376, the specimen in which the neck region is best preserved, 12 cervical centra are present (Fig.  4 A–C). These are exposed in right lateroventral view and show facets for dichocephalous ribs; therefore, we regard them as cervical vertebrae (following Sander, 1989 ). BES SC 999 also shows 12 cervical centra possessing both a diapophysis and a parapophysis (Fig.  4 C). Except for the presence of diapophyses and parapophyses, the cervical centra are generally circular along the transverse plane, but the cranial-most centra show a triangular ventral outline that becomes rounder towards the dorsal region. The height/length ratio of the cervical vertebrae is ~ 1.5, which is much greater than in Grippia longirostris (~ 1.24; Ekeheien et al., 2018 ), but slightly lower than in Cymbospondylus petrinus and Shastasaurus osmonti (both ~ 1.6; Merriam, 1902 , 1908 ).

Selected elements of the axial skeleton of Besanosaurus leptorhynchus . A , B portions of the axial skeleton of PIMUZ T 4376, including the cervical series and the anteriormost portion of the dorsal region; C BES SC 999, posteriormost cervical and anteriormost dorsal vertebrae; D BES SC 999, vertebrae belonging to the posterior half of the presacral dorsal series; E BES SC 999, sacral region and anteriormost portion of the caudal series; F BES SC 999, caudal vertebrae around the inferred position of the tailbend; G BES SC 999, caudalmost region of the tail. at atlas, ax axis, cac caudal centrum, car caudal rib, cec cervical centrum, cer cervical rib, chv chevron, Cl clavicle, Co coracoid, dc dorsal centrum, desr distal end of sacral rib, Fi fibula, ic intercentra, Il ilium, Is ischium, na neural arch, ns neural spine, oc occipital condyle, P pubis, S scapula, sc sacral centrum, sr sacral rib. Numbers indicate the relative position of the centra within each of the vertebral column sections (ce, cervical; d, dorsal; ca, caudal). The apostrophe (‘) indicates a left element. Scale bars represent 1 cm in A and B , 5 cm in C – F

The atlantal and axial pleurocentra are separate both in PIMUZ T 4376 and BES SC 999, although the atlantal pleurocentrum could only be identified in PIMUZ T 4376 (Fig.  4 A). The atlas in PIMUZ T 4376 shows a concave anterior articular facet, like in mixosaurids, shastasaurids and more derived ichthyosaurs, but unlike in Chaohusaurus and Cymbospondylus , in which it is convex (Huang et al., 2019 ; McGowan & Motani, 2003 ; Merriam, 1902 , 1908 ). The axial pleurocentrum does not show distinctive differences when compared to the more posterior cervical vertebrae. Three potential intercentra were also identified in PIMUZ T 4376 (Fig.  4 A). Diapophyses and parapophyses are always present on the cervical centra; the diapophyses project dorsolaterally and the parapophyses project ventrolaterally (more markedly in the large specimens than in the small ones). The diapophyses increase in size posteriorly towards the dorsal region, gradually transitioning from a round to a reniform outline, whereas the parapophyses decrease in size maintaining a rounded outline. Anteriorly, the diapophyses and parapophyses are separated from each other, the dorsoventral distance between them decreases posteriorly, and the parapophyses are no longer present on the 13th centrum, in which only an enlarged diapophysis is visible (Fig.  4 C). The diapophyses always contact the facets for the neural arch (Fig.  4 A–C).

In BES SC 999, the 12th centrum possesses a parapophysis that is extremely reduced in size (Fig.  4 C). A similar condition was described for Guizhouichthyosaurus tangae (Shang & Li, 2009 ) and Shastasaurus pacificus (Merriam, 1902 : pl. 8, fig. 3). In Shonisaurus sikanniensis there is a parapophysis on the first 10 and in the 12th presacral centra, whereas the 11th centrum only shows a single rib facet (Nicholls & Manabe, 2004 ). Around 10 cervical centra were identified in Guanlingsaurus liangae (Ji et al., 2013 ), whereas a parapophysis is visible up until the 9th centrum in the cervical series of Shonisaurus popularis (Camp, 1980 : fig. 28). The number of cervical vertebrae seems to be variable in Cymbospondylus . Sander ( 1989 ) identified six cervical vertebrae in Cymbospondylus buchseri , whereas Merriam ( 1908 : fig. 58) reported the presence of a parapophysis on the first 12 centra of Cymbospondylus petrinus . Furthermore, Fröbisch et al. ( 2006 ) noted the presence of a tiny parapophysis on the 8th presacral centrum of Cymbospondylus nichollsi and suggested the 9th to have only a rudimentary parapophysis.

Dorsal centra —Dorsal centra (i.e., non-cervical presacral centra) are generally circular in articular view, showing a regular and constant morphology along the vertebral column. The height/length ratio of the dorsal centra slightly increases posteriorly along the trunk region (~ 1.5 for the cranialmost dorsal centra; ~ 1.75 for the caudalmost dorsal centra), and the overall size of the centra increases from the neck towards the pelvis (in the holotype, the height of the 10th cervical centrum equals 31 mm and the height of the 46th dorsal centrum equals 49 mm). For comparison, the height/length ratio of the dorsal centra in Cymbospondylus buchseri (Sander, 1989 ) and Shastasaurus osmonti (Merriam, 1902 , 1908 ) is much greater than in Besanosaurus leptorhynchus with a mean value of ~ 2.

On the lateral side, the dorsal centra have only one articular facet for holocephalous ribs. The diapophysis is dorsoventrally long on all dorsal centra, has a concave cranial margin, and shows a slight constriction in the middle (Fig.  4 D). It is generally confluent with the anterior articular surface of the centrum, although never truncated by it (Fig.  4 D). This condition is more similar to Shastasaurus and Californosaurus (Merriam, 1902 , 1908 ) than to Cymbospondylus (Sander, 1989 , 1992 ), in which the diapophysis is visibly truncated by the anterior articular facet. The diapophysis contacts the facet for the neural arch up until at least the 37th or 38th dorsal centrum (the 49th and 50th centrum in general, respectively; Fig.  4 D). In comparison, in Cymbospondylus buchseri the connection between the rib facet and the neural arch is lost at the 29th dorsal centrum (35th centrum overall; Sander, 1989 ), in Cymbospondylus petrinus it is lost between the 24th and 26th dorsal centrum (36th–38th centrum in general; Merriam, 1908 ), in Californosaurus perrini it is lost in the 27th dorsal centrum (Merriam, 1902 ), and in Shonisaurus popularis it is already lost anterior to the 23rd dorsal centrum (Camp, 1980 ). The dorsal centra of Besanosaurus leptorhynchus differ greatly from those of Mixosaurus : in the latter, they are relatively longer (height/length ratio of a mid-dorsal centrum in BES SC 1000 is 1.45) and two rib facets are visible on the lateral side of the centra close to the pelvic region (e.g., Brinkman, 2004 ; Renesto et al., 2020 ). In lateral view, the dorsal centra of Besanosaurus leptorhynchus and Cymbospondylus are very similar. However, unlike in Cymbospondylus buchseri , the posterior dorsal vertebrae of Besanosaurus leptorhynchus , except for the last four caudalmost ones, possess a diapophysis located around or above the mid-height of the centrum that never shows the anteroventral extension visible in the dorsal centra of the caudal half of the trunk in Cymbospondylus buchseri (Sander, 1989 ). In addition, the typical triangular shape of the posterior dorsals in craniocaudal view of Cymbospondylus petrinus (Merriam, 1908 ) and likely Cymbospondylus buchseri (Sander, 1989 ) differs from Besanosaurus leptorhynchus , in which the centra are sub-pentagonal in shape (Dal Sasso & Pinna, 1996 ). The dorsal centra of Besanosaurus leptorhynchus are also similar to those of Shastasaurus osmonti (Merriam, 1902 ) in that they are sub-circular in outline in articular view. However, in Besanosaurus leptorhynchus the neural arch facets are raised markedly above the dorsal surface of the centrum in posterior dorsals, in contrast to Shastasaurus osmonti , in which they are proportionally much lower. In addition, the diapophysis almost never contacts the anterior articular surface of the dorsal centra in Shastasaurus osmonti and is dorsoventrally much taller than in Besanosaurus leptorhynchus .

Aberrant dorsal centra —In PIMUZ T 4376, the first eight dorsal centra (the 13–20 centra overall; Fig.  4 B) are remarkably narrow in lateral view in comparison with the preceding and following centra. Each of these centra measures about half of a normal centrum in length. We rule out the possibility that taphonomical compression selectively and plastically reduced the craniocaudal length of these eight centra since the associated elements (ribs and neural arches) maintain typical proportions. On the other hand, these centra are preserved packed closely to each other. To explain this particular condition, we tentatively suggest the existence of a developmental abnormality that affected the craniocaudal length of centra 13–20 in PIMUZ T 4376.

Sacral centra —We distinguish at least two sacral vertebrae in BES SC 999, identified by the presence of at least two large, disarticulated rib pairs with clearly expanded distal ends, that we recognise as sacral ribs (Fig.  4 E). Two sacral centra were also reported in Shonisaurus popularis (Camp, 1980 ) and Guizhouichthyosaurus tangae (Shang & Li, 2009 ). Sacral centra are also preserved in PIMUZ T 4376 but are not visible in PIMUZ T 1895 and T 4847. The sacral centra in Besanosaurus leptorhynchus occupy the 62nd and 63rd position along the vertebral column (and possibly two further positions caudally), so that the presacral vertebral count can be determined as 61. The sacral centra do not show diagnostic characters that can clearly differentiate them from the caudalmost dorsal centra and the cranialmost caudal centra. A gradual, slight increase in size in the caudal direction of the precaudal vertebrae makes the two sacral centra the largest in the entire axial skeleton (63rd centrum measures 52 mm in mediolateral width and 25 mm in craniocaudal length in BES SC 999).

In lateral view, both sacral vertebrae show a dorsoventrally elongated diapophysis that is reniform in outline and facets for neural arches that are enlarged lateromedially in the middle.

Caudal centra —BES SC 999 is the only specimen that possesses a complete, partially articulated tail (Figs. 2 , 4 , and 5 ). In this specimen, the caudal series (possessing at least 138 vertebrae) measures ~ 280 cm (measured along the vertebral column, without taking the tailbend into account), which is ~ 1.2 times the length of the rest of the body and accounts for 55.3% of the entire length of the axial skeleton. In the holotype, the tailbend is inferred to be present 155 cm caudally to the sacrum, based on the position of the tailbend preserved in PIMUZ T 1895 (see below). PIMUZ T 4376 also preserves an almost complete tail measuring ~ 104 cm, albeit it is mostly disarticulated and comprises at least 105 caudal centra, missing only the distalmost ones.

The size of the caudal centra decreases immediately posterior to the sacrum. Moreover, the postsacral centra gradually become more and more mediolaterally compressed. Centra that are clearly dorsoventrally taller than mediolaterally wide are visible posterior to the 30th caudal centrum of BES SC 999 (Figs.  4 F, and 5 D). From the cranialmost to the caudalmost position, the height/length ratio of caudal preflexural centra gradually changes from ~ 1.8 to ~ 2.8, whereas in the caudalmost postflexural preserved centra the ratio is ~ 1.65.

Wedge-shaped centra are visible on one of the slabs comprising PIMUZ T 1895, where at least five centra with a trapezoidal outline in lateral view can be recognised (Fig.  5 A). The neural spines corresponding to these centra are shorter than the preflexural neural spines and oriented vertically (Fig.  4 F). Neural spines positioned caudally to the tailbend become even shorter and cranially oriented. The tailbend in PIMUZ T 1895 possesses an angle of ~ 30°. In comparison, the tailbend reported in Guanlingsaurus liangae formed an angle of approx. 15° and the tailbend in Shonisaurus popularis formed an angle of only about 4° (Ji et al., 2011 ; McGowan & Motani, 1999 ). A slight tailbend was also reported for Cymbospondylus petrinus , but the angle it formed is not clear (Holger & Kosch, 1993 ).

Selected elements of the axial skeleton of Besanosaurus leptorhynchus . A , B PIMUZ T 1895, tailbend region and anteriormost region of the presacral vertebral series, respectively; C two chevrons belonging to PIMUZ T 4847; D BES SC 999, anteriormost portion of the tail. a astragalus, c centrum, cac caudal centrum, car caudal rib, chv chevron, Cl clavicle, dia diapophysis, Fi fibula, Il ilium, Is ischium, na neural arch, ns neural spine, S scapula, sc sacral centrum, sr sacral rib. Numbers indicate the position of the centra within each of the vertebral column sections (ce, cervical; d, dorsal; ca, caudal). The apostrophe (‘) always indicates a left element. Scale bars represent 5 cm

In BES SC 999, the cranialmost 4 or 5 caudal centra, unlike the following ones, lack haemal arches (Fig.  5 D). The last ossified caudal ribs likely articulate with the sixth caudal centrum. In BES SC 999, PIMUZ T 4376, and PIMUZ T 1895, caudal centra between the 6th position and the wedge-shaped centra still show small and rounded diapophyses, which are visible up until the tailbend (PIMUZ T 1895), indicating they likely articulated with non-ossified elements (Fig. 5 A, D ). In the proximal-most caudal centra, the diapophysis contacts the anterior margin of the centrum (at least until the 10th caudal position in BES SC 999), although it does not merge with the cranial articular facet. From the proximal to the caudal-most caudal where a diapophysis is visible, they gradually decrease in size until they are a point-like element in caudal centrum 55 (PIMUZ T 1895). A similar condition is seen in Shonisaurus popularis (Camp, 1980 ) and Cymbospondylus petrinus (Merriam, 1908 ).

The presence of articular surfaces for ribs, as well as the change in the direction of the dorsoventral axis of the neural spines, was used to infer the location of the tailbend in BES SC 999: the positions of the apical centra are inferred as positions 56–60 in the caudal series (Fig.  4 F).

Neural arches and spines —In PIMUZ T 4376, most of the presacral neural arches are exposed in right lateral view and preserved in articulation (Fig.  4 A, B ). In PIMUZ T 4376, the element previously described as possible opisthotic (Bindellini et al., 2021 ) is here reidentified as the atlantal neural arch (Fig.  4 A). PIMUZ T 1895 shows a well-preserved articulated series of neural arches in the cranial most portion of the trunk (Fig.  5 B). In BES SC 999, the neural arches are also well preserved, although they are sometimes partly covered by other bones (Fig.  4 C–G).

Among the studied specimens, only PIMUZ T 4376 shows a well-preserved axis (Fig.  4 A); its neural arch has a craniocaudally expanded neural spine, around two times broader than the subsequent spines.

In general, the neural arches possess a triradiate outline in cranial/caudal view. The pedicle is as long anteroposteriorly as the length of the centrum; the medial margin of the articular surface is straight, whereas the lateral margin shows a lateral bulge. This expansion is clearly visible up until the 38th/39th centrum, which are the last two centra where the facet for the neural arch contacts the diapophysis (see description of dorsal centra; Fig.  4 D). Prezygapophyses and postzygapophyses are of similar size in the cervical and anterior dorsal vertebrae; in the posterior dorsal and anterior caudal vertebrae, the prezygapophyses project cranially more than the postzygapophyses do caudally (Figs. 4 and 5 ). The zygapophyses are paired, similar to the condition in Shastasaurus osmonti and Cymbospondylus (Merriam, 1908 ; Sander, 1989 ), but unlike in post-Triassic ichthyosaurs, in which the anterior neural arches show unpaired zygapophyses (e.g., McGowan & Motani, 2003 ; Moon & Kirton, 2016 ). The articular surfaces of the zygapophyses are almost horizontal (Figs. 4 and 5 ).

In lateral view, the dorsal neural spines of Besanosaurus leptorhynchus are craniocaudally expanded dorsally, with a generally convex dorsal margin, more rounded than what is visible in Cymbospondylus buchseri (Sander, 1989 ) and Phantomosaurus neubigi (Sander, 1997 ) (this feature is more evident in the caudalmost dorsal vertebrae). The neural spines are inclined at an angle that varies along the vertebral column: cervical and dorsal neural spines are posteriorly inclined at an angle of about 25° from the vertical axis (as also described for Cymbospondylus buchseri ; Sander, 1989 ) and near the inferred position of the sacrum the neural spines become more vertical. More caudally, the anterior caudal neural spines are posteriorly inclined at an angle of about 15° (Fig.  5 D). The caudal neural spines, in the first half of the tail, are inclined posteriorly almost at an angle of 45°, but posterior to the tailbend, the spines become abruptly shorter and vertically oriented, whereas more caudally their inclination becomes inverted, i.e., the dorsoventral axis of the neural spines changes direction pointing anteriorly (Dal Sasso & Pinna, 1996 : fig. 14). Taller neural spines, visible just before the wedge-shaped flexural centra, likely supported a low dorsal lobe of the tail fluke.

Haemal arches (chevrons) —In BES SC 999, chevrons are visible starting from the 5th or 6th caudal centrum. In cranial/caudal view most of the chevrons are Y-shaped, but the caudalmost chevrons are V-shaped (Fig. 5 A, C , D ). In lateral view, the chevrons are straight and the cranialmost ones are dorsoventrally taller than the corresponding centrum (Fig.  5 D). Approaching the tailbend, the dorsoventral height of the chevrons gradually decreases, whereas their mediolateral width remains constant (Figs. 4 and 5 ). Caudally to the tailbend, haemal arches keep decreasing in size, also showing a clear mediolateral width reduction (Fig. 4 F, G ) if compared to the more anterior chevrons. In both BES SC 999 and PIMUZ T 4376, tiny haemal arches are visible extending almost until the very tip of the tail (Fig.  4 G). This condition contrasts with parvipelvians (excluding Ichthyosaurus communis ) and basal euichthyosaurians (e.g., Californosaurus perrini ), in which the haemal arches are reduced in size and disappear more cranially (e.g., McGowan & Motani, 2003 ; Merriam, 1902 ; Moon & Kirton, 2016 ).

In BES SC 999 and PIMUZ T 4376, the ribcage is complete and most ribs are spaced as in vivo; in PIMUZ T 4847 and PIMUZ T 1895 the ribcage is only partly complete (Figs. 2 and 3 ). At the level of the 55th presacral vertebra, the ribs gradually become shorter and, as a result, the trunk tapers approaching the pelvic region. Post-scapular rib heads are exclusively holocephalous (Figs. 4 and 5 ), a condition similar to that in Cymbospondylus (e.g. Sander, 1989 ) and other non-euichthyosaurian ichthyosaurs (e.g., Camp, 1980 ; Merriam, 1902 ; Nicholls & Manabe, 2004 ; Shang & Li, 2009 ). In BES SC 999, the longest rib (articulating with the 29th presacral vertebra) is 46 cm long. In cross-section, the ribs are approximately eight-shaped with a clear furrow running both on the cranial and caudal surface throughout their whole length. The presence of these furrows may be partially the result of trabecular bone collapse, nonetheless they are also clearly visible in PIMUZ T 4376, in which the anatomy of the bones is preserved more three-dimensionally.

Cervical ribs —Cervical ribs are dichocephalous (Fig. 4 A, C ). They are located cranially to the scapulae. The capitulum and tuberculum are round and small, and separated by a small notch. The shafts of the cervical ribs are slightly curved laterally and the distal ends taper into pointed tips. The anterior and posterior furrows of the cervical ribs extend to the level of at least the 8th centrum and are shallower than those in the dorsal ribs, resulting in a less constricted cross-section of the midshaft. In PIMUZ T 4376, the rib articulating with the axis is the shortest among the preserved presacral ribs, being as long as the width of the adjacent centrum. Cervical ribs gradually increase in length, so that the last cervical rib reaches one-third of the length of the longest dorsal rib.

Dorsal ribs —Dorsal ribs are holocephalous (Figs. 4 and 5 ) and located posteriorly to the scapula. They reach their greatest length posterior to the 15th dorsal centrum and maintain a constant length almost up to the sacral region. The head region is slightly sigmoidal in craniocaudal view, similar to what can be observed in Cymbospondylus buchseri (PIMUZ T 4351, MSNM V927). The proximal end is also dorsomedially expanded and the articular surface of the head matches the profile of the long and curved (cranially concave) diapophysis. Proximal and distal ends are equally broadened.

Sacral ribs —We distinguish two unambiguous pairs of sacral ribs in BES SC 999 (Fig.  4 E). These sacral ribs are preserved lying close to each other and are located in close proximity to the ilia. They clearly show an expanded distal end that was likely connected with or located immediately adjacent to the distal portion of the ilium, as in Guizhouichthyosaurus tangae (Shang & Li, 2009 ). The proximal ends of the sacral ribs are also expanded, but not as much as the distal ends. In BES SC 999, the distal articular surfaces of the sacral ribs show a degree of rugosity greater than in the adjacent ribs. Both in the holotype and in PIMUZ T 4376, two additional pairs of ribs with enlarged distal ends are present, but their intermediate morphology (see below) does not allow for their unambiguous identification as sacral ribs. In PIMUZ T 4376, these two further pairs of potential sacral ribs are very short, straight, and possess a thickened midshaft in comparison with the caudalmost dorsal ribs and the rostralmost caudal ribs.

Caudal ribs —As mentioned above, the last ossified caudal rib likely articulated with the sixth caudal centrum, as is visible in BES SC 999 (Fig.  4 E). Between the 6th caudal centrum and the caudal peak, small and rounded articular surfaces for ribs are visible on the lateral sides of the centra in BES SC 999, PIMUZ T 4376, and PIMUZ T 1895. However, the corresponding caudal ribs are not preserved in any of the three specimens, suggesting that these ribs were likely unossified. The ossified caudal ribs are short, straight, and rod-like, with dorsoventrally expanded proximal and distal ends. The last preserved caudal rib terminates in a pointed distal tip and shows an approximately compressed-conical morphology (Fig.  5 D).

All specimens preserve gastralia, usually scattered and often broken, but PIMUZ T 1895 and BES SC 999 preserve some articulated elements (Figs. 2 and 3 ; Fig. S1). Given their state of preservation, it is difficult to estimate the exact number of gastral ribs. Each gastral rib consisted of five elements: one median unpaired element and two lateral paired elements, like in Cymbospondylus (Sander, 1989 ) and Mixosaurus (Renesto et al., 2020 ). The median element is boomerang-shaped with an angle of 135°–140° (145° in Cymbospondylus buchseri ; Sander, 1989 ). It possesses a short median anterior process, which is less well-developed in the smaller specimens (PIMUZ T 4376 and PIMUZ T 1895) (Figs. 2 and 3 ). The element that connects the median to the lateralmost gastralium is a thin recurved bone with pointed medial and lateral ends. The lateralmost element shows a slightly sigmoidal lateral end and a recurved medial end. As reported for the ribs, two shallow furrows are visible on the cranial and caudal surfaces of each gastral element. As in the case of the ribs, these furrows may be to some degree the result of trabecular bone collapse. The gastral basket extended from immediately posterior to the coracoids to the caudalmost region of the trunk.

Appendicular skeleton

Pectoral girdle.

Scapula —The scapulae are well preserved in BES SC 999 and PIMUZ T 4376 (Fig. 6 A–C). In the holotype, the right scapula is exposed in mediodorsal view, whereas the left one is exposed in lateroventral view; in PIMUZ T 4376, we observe the opposite condition. In PIMUZ T 1895 and PIMUZ T 4847, both scapulae are fragmentary and not well preserved (Figs.  3 and 6 D).

The left ( A ) and right ( C ) forefin and shoulder girdle elements of BES SC 999, and forefin and shoulder girdle elements of PIMUZ T 4376 ( B ) and PIMUZ T 4847 (D). Cl clavicle, Co coracoid, CoHf coracoid facet for the humerus, H humerus, HSf humerus facet for the scapula, Haf anterior flange of the humerus, HCof humerus facet for the coracoid, Hdpc deltopectoral crest of the humerus, Hh humerus head, HRf humerus facet for the radius, HUf humerus facet for the ulna, i intermedium, icof intercoracoidal facet, r radiale, R radius, RHf radial facet for the humerus, S scapula, Sglec glenoid contribution of the scapula, SCof scapular facet for the coracoid, U ulna. The apostrophe (‘) always indicates a left element. In A , B , and C scale bars represent 5 cm; in D it represents 25 cm

Overall, the scapula is flat with a relatively thicker, dorsoventrally expanded proximal end. The anterior flange of the scapula is absent, whereas the posterior extension is large and prominent, resulting in the general profile of the scapula resembling an asymmetrical fan. The longitudinal axis of the scapula is oriented at ~ 20° with respect to the glenoid facet. At the proximal end, in medioventral view, the facet for the coracoid extends craniocaudally and measures more than twice the length of the glenoid facet; on the other hand, the glenoid facet has a larger contribution in lateroventral view. The articular facet for the coracoid in the right scapula of BES SC 999 shows a rugose surface indicating the presence of a considerable amount of cartilage in vivo. A small neurovascular foramen is visible perforating the scapular blade anteroproximally. On the visible surfaces, radial striations extend from the ossification centre to the margins of the bone.

The scapula of Besanosaurus leptorhynchus closely resembles that of Guizhouichthyosaurus tangae (Shang & Li, 2009 ), although the latter is proportionally slightly shorter proximodistally. However, unlike in Shastasaurus , the scapula of Besanosaurus leptorhynchus does not possess an anteroproximal notch (Merriam, 1902 : pl. 10 and pl. 12) and unlike in ‘ Callawayia ’ wolonggangense , the scapula of Besanosaurus leptorhynchus does not possess a small anteroproximal extension (Chen et al., 2007 : fig. 3B). The scapula of Besanosaurus leptorhynchus also differs markedly from the scapulae of Shonisaurus popularis (Camp, 1980 : fig. 40), Shonisaurus sikanniensis (Nicholls & Manabe, 2004 : fig. 12), Callawayia neoscapularis (McGowan, 1994 : fig. 6) and parvipelvian ichthyosaurs, in which the posterior extension of the scapula is reduced and forms an elongate blade (Maisch & Matzke, 2000 : char. 71).

Coracoid —BES SC 999 preserves a complete left coracoid exposed in ventral view; in PIMUZ T 4376 both coracoids are complete, but only the right one is clearly visible and exposed in dorsal view. PIMUZ T 4847 preserves both coracoids, although they are not well preserved (Fig.  6 B).

The coracoids of Besanosaurus leptorhynchus are plate-like elements that are craniocaudally longer than mediolaterally broad and possess a deep, cranial notch. As a result, they superficially resemble a broad axe head in outline. The proximal end is more prominent and broader in BES SC 999 and PIMUZ T 4847 than in PIMUZ T 1895 and PIMUZ T 4376. Proximally, the scapular facet and the glenoid facet are in continuity with each other, although the glenoid contribution is almost two times dorsoventrally taller than the scapular facet. The cranial margin of the coracoid is characterised by the presence of an anterior notch that is much deeper in PIMUZ T 4847 than in PIMUZ T 4376, with an intermediate condition visible in BES SC 999. The caudal margin is slightly concave, with a clear posterior notch being absent. The medial margin, which forms the intercoracoid facet (with a possible craniomedial contact for the interclavicle) is long and rounded.

CT images of the left coracoid of BES SC 999 reveal the presence of a slightly concave dorsal surface and a convex ventral surface. As in the scapula, radial striations extend from the ossification centre to the margins of the bone.

As in other shastasaur-grade ichthyosaurs (e.g., Guizhouichthyosaurus tangae , Shang & Li, 2009 ; Shastasaurus osmonti , Merriam, 1902 ; Shonisaurus sp., Camp, 1980 ; Callaway & Massare, 1989 ; Nicholls & Manabe, 2004 ), both the cranial and caudal margins of the coracoid are concave in Besanosaurus leptorhynchus . However, the coracoid of Besanosaurus leptorhynchus is proportionally shorter mediolaterally than in the abovementioned taxa and its distal margin is concave, not straight. The craniocaudal length of the coracoid peduncle (sensu Maisch & Matzke, 2000 ) is more than half the length of the coracoid itself, similar to Shastasaurus osmonti (Merriam, 1908 ), Shonisaurus popularis (Camp, 1980 ), and Guizhouichthyosaurus tangae (Shang & Li, 2009 ). The cranial (preglenoidal, sensu Maisch & Matzke, 2000 ) extension of the coracoid in Besanosaurus leptorhynchus is greater than the caudal (postglenoidal) portion, as described for other shastasaur-grade ichthyosaurs (e.g., Maisch & Matzke, 2000 ); however, this latter portion in Besanosaurus leptorhynchus is proportionally smaller than in ‘ Callawayia’ wolonggangense and Guizhouichthyosaurus tangae (Chen et al., 2007 ; Shang & Li, 2009 ).

Clavicle— Both clavicles are well preserved in BES SC 999 and PIMUZ T 4376 (Figs. 2 and 6 ; Fig. S2). In the latter, these bones are both exposed in dorsal view, whereas in the holotype the right clavicle is exposed in ventral view and the left one is rotated by 180° and exposed in dorsal view.

The clavicles are long and slender, gently broadened at midshaft, and gently curved towards the glenoid region. Proximal ends are slightly expanded whereas distally the clavicles taper to a pointed end. The dorsal surfaces of the clavicles are convex, the ventral ones are concave: in the distal half, this concavity consists of a deep groove that is shallower proximally. As reported in Guizhouichthyosaurus tangae (Shang & Li, 2009 ), the medial margins articulate with the central interclavicle, so that the three elements form a continuous recurved cranial margin. The caudal tip of the clavicle contacts the scapula lateroventrally, as indicated by a specific dorsomedial articulation surface for the clavicle on the scapula. The clavicles of Besanosaurus leptorhynchus are similar to those of Shastasaurus osmonti (Merriam, 1902 ), Guizhouichthyosaurus tangae (Shang & Li, 2009 ), and Shonisaurus popularis (Camp, 1980 ), although in the latter taxon they are proportionally much shorter.

Interclavicle— The only specimen in which an interclavicle is visible is PIMUZ T 4376 (Fig.  6 B; Fig. S3). This bone is T-shaped, with proportionally long lateral processes contacting the clavicles cranially, and what seems to be a broad, proportionally short, triangular caudal process. An ossified rod of the caudal process of the interclavicle is apparently missing. This could be due to the early ontogenetic stage of the specimen, due to its loss during fossilisation, or due to its actual absence. It is unclear if the interclavicle prevented the two clavicles from contacting each other or not. The interclavicle of Besanosaurus is similar to that of ‘Callawayia’ wolonggangense (Chen et al., 2007 : fig. 3B). The preserved portion of the interclavicle is also similar to Guizhouichthyosaurus tangae (Shang & Li, 2009 ), except for the absence of the posterior rod. In comparison, the interclavicle of Mixosaurus cornalianus (BES SC 1000) has a short and robust caudal process that does not produce a posterior rod (Renesto et al., 2020 ). Also, the interclavicles of Besanosaurus leptorhynchus and Guizhouichthyosaurus tangae clearly differ from that of Shonisaurus sikanniensis , which possesses a mediolaterally expanded posterior rod and shortened lateral processes (Nicholls & Manabe, 2004 ).

None of the specimens show fully articulated and complete forefins; however, the left stylopodium and zeugopodium of BES SC 999 are preserved in articulation. Each element of the forelimb is suboval to rounded in outline, except for the elements that possess an anterior or posterior notch. The zeugopodium of Besanosaurus leptorhynchus is ~ 66% the length of the stylopodium. The manus possesses four primary digits (II–V; Motani, 1999 ) and one accessory digit. The phalanges are well-separated, likely surrounded in vivo by a considerable amount of cartilage, in contrast to the hindlimbs, where the phalanges are tightly packed together and retain rudimentary shafts. The roundness of the forelimb elements is shared both by small and large (PIMUZ T 4376, BES SC 999, PIMUZ T 4847) individuals; this character, which we suspect to be paedomorphic, is also shared with Guizhouichthyosaurus tangae (Shang & Li, 2009 , 2013 ), Guanlingsaurus liangae (Ji et al., 2013 ) and to a lesser extent, at least in the phalanges, in other shastasaur-grade ichthyosaurs (Camp, 1980 ; Chen et al., 2007 ; Merriam, 1902 , 1908 ).

Humerus —PIMUZ T 4376 is the only specimen that preserves both humeri completely. In this specimen, the humeri are slightly craniocaudally broader than proximodistally long (Fig.  6 B). The same is true for the left humerus of BES SC 999, but not for the right one, which shows an opposite condition (Table  1 ). This difference is likely attributable to different stresses that acted on both specimens during the process of fossilisation, resulting in shape distortion caused by compression. PIMUZ T 1895 and PIMUZ T 4847 possess incomplete and fragmentary humeri.

In dorsal/ventral view, the distal width of the humerus is slightly greater than its proximal width. The anterior flange of the humerus is present but reduced (Motani, 1999 ). The anterior flange bears a shallow notch in its middle in PIMUZ T 4376, and a proportionally deeper notch is present in BES SC 999. On the dorsal side of the humerus, the head is directed proximodorsally, as in other shastasaur-grade ichthyosaurs (Motani, 1999 ). On the ventral side, the deltopectoral crest appears to be only slightly raised, but this might be the result of taphonomical compression. Likely for the same reason, the posterodistal tuberosity seems to be flat. A deltopectoral ridge runs distally from the deltopectoral crest towards the centre of the ventral surface.

In BES SC 999, on the dorsal side of the proximal end of the humerus, the facet for the scapula is visible. Symmetrically, on the ventral side, a small portion of the facet for the coracoid is visible. However, both these articular surfaces are not well preserved in the holotype, and in the other specimens these features are not clearly visible. The distal end of the humerus hosts a relatively large, slightly concave, and anterodistally directed facet for the radius; the facet for the ulna is directed posterodistally. Judging from the CT images of BES SC 999, the radial facet is ~ 1.5 times longer than the ulnar facet.

The humerus proportions in Besanosaurus leptorhynchus resemble those in Pessosaurus polaris (PMU 24585 = PMU R176; Motani, 1999 : fig. 3; GB, pers. obs.) and Guanlingsaurus liangae (Ji et al., 2013 ; Sander et al., 2011 ). In contrast, in Pessopteryx nisseri (Wiman, 1910 ) and Guizhouichthyosaurus tangae (Shang & Li, 2009 ) the humerus is proximodistally longer than craniocaudally wide . On the other hand, the humerus of Besanosaurus leptorhynchus is more rounded than in Callawayia neoscapularis (McGowan, 1994 ), Shonisaurus popularis (Camp, 1980 ), Shastasaurus osmonti (Merriam, 1902 , 1908 ) and ‘ Callawayia ’ wolonggangense (Chen et al., 2007 ), in which the posterior margin of the humerus is proximodistally taller than the anterior margin and distinctly concave.

Radius —The radius is the second largest bone in the forefin. Like in the case of the humeri, both radii are complete and well-preserved in BES SC 999 and PIMUZ T 4376 (Fig.  6 A–C). The ?right radius is also preserved in PIMUZ T 4847 (Fig.  6 D).

The radius lies cranially to the ulna and contacts the humerus proximally: the facet for the latter is straight and long and corresponds to the anterodistally directed radial facet at the distal end of the humerus. The radii in BES SC 999 and PIMUZ T 4376 possess an approximately squared profile in dorsal/ventral view and are only slightly craniocaudally broader than proximodistally long. On the other hand, the ?right radius of PIMUZ T 4847 shows an opposite condition (Table  2 ). The different proportions of the radii in PIMUZ T 4847 and PIMUZ T 4376 are likely related to ontogeny, taphonomy, or a combination of both. The anterior margin of the radius is characterised by the presence of a proximodistally wide notch in the adults; this notch is shorter and shallower in the juvenile. The caudal margin of the radius is characterised by the presence of a shallow concavity adjacent to the proximal end, which might have accommodated a small portion of the rounded proximocranial margin of the ulna.

The radius of Besanosaurus leptorhynchus is most similar to those of Guizhouichthyosaurus tangae (Shang & Li, 2013 ) and Shastasaurus osmonti (Merriam, 1902 , 1908 ), which are also subrectangular in outline (although slightly broader craniocaudally than tall proximodistally) and also bear a notch anteriorly. In Pessosaurus polaris , Shonisaurus popularis and Callawayia neoscapularis , the radius is craniocaudally markedly broader than it is proximodistally tall and possesses a cranial margin that is proximodistally longer than the caudal margin, a straight, weakly concave or notched cranial margin, and a weakly concave or notched caudal margin (Camp, 1980 ; Motani, 1999 ; Nicholls & Manabe, 2001 ). In contrast, the radius of Guanlingsaurus liangae is suboval in outline, but with the anterior margin also proximodistally longer than the caudal one (Sander et al., 2011 ).

Ulna —Both ulnae are preserved in PIMUZ T 4376 and BES SC 999 (Fig.  6 A–C). In the latter specimen, the ulnae are preserved close to their in vivo position, although the left one is incomplete, whereas in PIMUZ T 4376 they are disarticulated. An incomplete ulna is also preserved in PIMUZ T 4847. The ulna is always subcircular in outline and slightly smaller than the radius.

In contrast to Besanosaurus leptorhynchus , the ulna in Guanlingsaurus liangae is suboval in outline, being anteroposteriorly broader than proximodistally long (Sander et al., 2011 ). In Shastasaurus osmonti and Callawayia neoscapularis the ulna is also anteroposteriorly longer than proximodistally broad, but is subrectangular in outline (Merriam, 1902 , 1908 ; Nicholls & Manabe, 2001 ). Yet another type of ulnar morphology is present in Guizhouichthyosaurus tangae and Shonisaurus popularis , in which the ulna is proximodistally longer than anteroposteriorly broad (Camp, 1980 ; Shang & Li, 2009 , 2013 ). In the ulnae of both PIMUZ T 4376 and BES SC 999, the roundness (ratio between the inscribed and the circumscribed circles) equals ~ 0.8. In comparison, this ratio equals 0.67 in Guizhouichthyosaurus tangae (Shang & Li, 2009 ) and 0.61 in Callawayia neoscapularis (McGowan, 1994 ).

Carpus —The proximal and distal carpals of Besanosaurus leptorhynchus possess a generally subcircular profile and shafts of the bones are not retained. The radiale is the largest among the carpals, with the intermedium being slightly smaller. The ulnare and all other carpal elements are smaller than the intermedium (Figs. 2 , 6 , and 7 ).

3D reconstruction of the scapular girdle and forefins of Besanosaurus leptorhynchus based on the CT scans of BES SC 999 in laterofrontal ( A ), frontal ( B ), and ventral ( C ) view. Original elements in white; elements reconstructed on the basis the available material in grey. Scale bars represent 50 cm. Note that the forefin elements were subject to extreme dorsoventral compression post-mortem and appear much more flattened in the reconstruction than they would be in vivo

In BES SC 999, where the carpal elements are preserved relatively close to their original position, three proximal carpals (radiale, intermedium, and ulnare) and four distal carpals can be identified. One small and rounded distal element, likely representing a pisiform, is also visible. It likely articulated caudally with the two carpal rows, similar to the condition in Guizhouichthyosaurus tangae (Shang & Li, 2009 ). The radiale and ulnare are almost perfectly circular, whereas the intermedium seems to be slightly proximodistally longer than craniocaudally wide.

In BES SC 999 and PIMUZ T 4376, the radiale does not bear a notch; only the ?right radiale of PIMUZ T 4847 has a notch on its anterior margin. In BES SC 999, the ?posterior margin of the right intermedium is notched, whereas the left one is rounded like the other carpals. Therefore, the presence of a notch on the cranial or caudal margin of the proximal carpals was variable in Besanosaurus leptorhynchus . Among shastasaur-grade ichthyosaurs, a non-notched radiale was reported in Guizhouichthyosaurus tangae (Shang & Li, 2009 ) and Shastasaurus osmonti (Merriam, 1902 ), whereas in Shonisaurus popularis both notched and non-notched radialia were reported (Camp, 1980 ; Sander, 2000 ).

Metacarpus and manual phalanges —Metacarpals and manual phalanges are preserved in BES SC 999, PIMUZ T 4376, and PIMUZ T 4847 (Figs. 2 , 3 ). In BES SC 999, almost all phalanges are preserved and scattered on the surface of the slabs comprising the right forefin. The metacarpals and the manual phalanges are all subcircular in outline. Besanosaurus leptorhynchus almost certainly had four primary digits (representing primary digits II–V; Motani, 1999 ), with digit V possessing markedly smaller phalanges compared to the other three digits. Following this interpretation, Besanosaurus leptorhynchus is the stratigraphically oldest ichthyosaur reported to date, showing the loss of primary digit I (Motani, 1999 ). We estimate the presence of at least 20 phalanges in the longest primary digit (III). The autopodium (estimated to measure ~ 55 cm in BES SC 999) is longer than the stylopodium+zeugopodium. Phalanges are not packed close to each other, but are well separated, likely surrounded in vivo by a considerable amount of cartilage. According to our reconstruction, a few tiny elements belonging to a postaxial accessory digit are also present; these phalanges and their arrangement are similar to those in Guizhouichthyosaurus tangae , although in the latter the postaxial accessory digit has a higher number of phalanges (Shang & Li, 2013 ). Rounded phalanges are also present in Shastasaurus osmonti , Californosaurus perrini (Merriam, 1902 ) and Shonisaurus popularis (Camp, 1980 ). However, the latter possesses a notch on the cranial margin of each element of the autopodium, a character absent in Besanosaurus leptorhynchus.

Pelvic girdle

The ilium of Besanosaurus leptorhynchus is similar in size to the other pelvic bones, as in other shastasaur-grade ichthyosaurs (Camp, 1980 ; Ji et al., 2013 ; Merriam, 1908 ; Shang & Li, 2009 ) and Callawayia neoscapularis (Nicholls & Manabe, 2001 ), but differs from Cymbospondylus (Merriam, 1908 ), Mixosaurus (Repossi, 1902 ) and Californosaurus perrini (Merriam, 1902 ), in which the ilium is markedly smaller than the other pelvic bones.

The pubis and ischium of Besanosaurus leptorhynchus are nearly equal in size, with the ischium being slightly smaller than the pubis, as is also the case in Cymbospondylus (Merriam, 1908 ), Guizhouichthyosaurus tangae (Shang & Li, 2009 ), and Shonisaurus popularis (Camp, 1980 ), but differs from the condition in Shastasaurus osmonti (Merriam, 1902 ), Guanlingsaurus liangae (Ji et al., 2013 ) and Callawayia neoscapularis (Nicholls & Manabe, 2001 ), in which the two bones are sub-equal in size, and Californosaurus perrini (Merriam, 1902 ), in which the ischium is slightly larger than the pubis.

Ilium —The ilia are well preserved in BES SC 999 and PIMUZ T 4376. In PIMUZ T 4847, only an incomplete element resembling the ?left ilium is preserved (Fig. 8 A, B , and D ). In BES SC 999, the left ilium is obscured from external view by other bones but is well visible in CT images (Fig.  8 ).

Left ( A ) and right ( C ) hindfin and pelvic girdle elements of BES SC 999; ( B ) CT scan rendering of the right pelvic girdle and forefin elements of BES SC 999; (D) hindfin and pelvic girdle elements of PIMUZ T 4376; ( E ) right femur of PIMUZ T 4376; ( F ) femur of PIMUZ T 4847; ( G , H ) left and right femora of BES SC 999. a astragalus, c calcaneum, Fe femur, Feadp femur anterodistal process, Fedp dorsal process of the proximal epiphysis of the femur, FeFif femoral facet for the fibula, FeTf femoral facet for the tibia, Fevp ventral process of the proximal epiphysis of the femur, Fi fibula, Il ilium, Is ischium, P pubis, Pof obturator foramen of the pubis, Sr sacral rib, T tibia; 2, 3, and 4, distal tarsals; II, III, IV, and V, metatarsals. The apostrophe (‘) always indicates a left element. Scale bars represent 5 cm in A – D , and 1 cm in E – H

The ilium has a craniocaudally expanded proximal end that participated in the acetabulum and a craniocaudally expanded distal end that likely contacted the expanded distal ends of the two pairs of sacral ribs, as inferred for Guizhouichthyosaurus tangae (Shang & Li, 2009 ). The distal end of the ilium is craniocaudally wider than the proximal end, similar to Mixosaurus (Repossi, 1902 ), Shastasaurus osmonti (Merriam, 1902 , 1908 ), and adult Guanlingsaurus liangae (Ji et al., 2013 ), but is different from the condition in Cymbospondylus (Merriam, 1908 ), Guizhouichthyosaurus tangae (Shang & Li, 2009 ), juvenile Guanlingsaurus liangae (Ji et al., 2013 ), Callawayia neoscapularis (Nicholls & Manabe, 2001 ) and Californosaurus perrini (Merriam, 1902 ), in which the proximal and distal ends of the ilium are of approximately equal width in lateral view. In BES SC 999, both the proximal and distal ends are also highly rugose, suggesting the presence of cartilage in vivo. The shaft of the ilium appears to have been lateromedially flattened relative to the likely thickened proximal end in vivo (compare with Camp, 1980 ). The right ilium of BES SC 999 and the ?left ilium of PIMUZ T 4847 are preserved in approximately anterolateral/posterolateral view, although they have undergone severe compression. The ilia are slightly curved so that the preserved concave margins correspond to their medial surfaces (compare with Camp, 1980 : fig. 51). This is similar to Shastasaurus (Merriam, 1908 : pl. 16, fig. 4) and recalls the basal ichthyopterygian ilium morphology also present in Utatsusaurus (Motani, 1998 ). A similar curvature of the ilium is also preserved in adult specimens of Guanlingsaurus (Ji et al., 2013 : fig. 5) and Callawayia neoscapularis (Nicholls & Manabe, 2001 : fig. 11). The curvature is less pronounced in Californosaurus perrini (Merriam, 1902 ). In PIMUZ T 4376 this curvature is not visible because the ilium is preserved in lateral view; in BES SC 999, the left ilium is preserved in the form of a straight element as well.

Pubis —Both pubes are well preserved in BES SC 999 and PIMUZ T 4376 (Fig.  8 ); a poorly preserved element resembling a pubis is also visible in PIMUZ T 4847.

The pubis is plate-like. Its anterolateral margin is concave, whereas the rest of the bone shows a suboval outline interrupted only by the aperture of the obturator foramen on its caudal margin. The proximal margin, probably bordering one-third of the cranioventral margin of the acetabulum, is dorsoventrally slightly thicker than the rest of the bone. The obturator foramen opens to the caudal margin in all examined specimens. As reported in previous studies (McGowan & Motani, 2003 ; Motani, 1999 ; Dal Sasso & Pinna, 1996 ), the obturator foramen shows an elongated, suboval outline, being almost entirely enclosed within the pubis in the holotype BES SC 999, and slightly open in PIMUZ T 4376. The condition in PIMUZ T 4847, the largest specimen, is uncertain. Among basal Merriamosauria, Guizhouichthyosaurus tangae (Shang & Li, 2009 ) shares the most similar pubis morphology with Besanosaurus leptorhynchus . Shastasaurus (Merriam, 1902 ) also shows a similar morphology but possesses a much more rounded medial margin both in the pubis and the ischium. In dorsal and ventral view, the pubis of Besanosaurus leptorhynchus recalls the pubis of Californosaurus perrini in outline, but the latter shows a much wider aperture of the obturator foramen (Merriam, 1902 ). A relatively narrow obturator foramen is also present in Shastasurus osmonti (Merriam, 1908 : fig. 73; Dal Sasso & Pinna, 1996 : fig. 21), but it is still broader than that in Besanosaurus leptorhynchus .

Ischium— Both ischia are well preserved in BES SC 999 and PIMUZ T 4376 (Fig.  8 ); a possible ischium is also preserved in PIMUZ T 4847. The ischium is a plate-like, fan-shaped bone, which is slightly smaller than the pubis. In ventral and dorsal view, the bone forms a convex anteromedial/ventromedial margin and a concave caudolateral margin. The proximal end of the bone appears dorsoventrally slightly thicker than the rest of it and forms the caudoventral margin of the acetabulum.

Overall, the morphology of the ischium of Besanosaurus leptorhynchus is similar to that of basal Merriamosauria, in which this bone is preserved [ Guizhouichthyosaurus tangae (Shang & Li, 2009 ); Shastasaurus pacificus (Merriam, 1908 ); Shonisaurus popularis (Camp, 1980 ); Californosarus perrini (Merriam, 1902 )]. In contrast to basal ichthyopterygians (Motani et al., 1998 , 2014 ; Wiman, 1929 ), some mixosaurids (e.g., Brinkmann, 2004 ), and Toretocnemus (Merriam, 1903 ), the medial symphysis between the pubes and ischia in Besanosaurus leptorhynchus is not straight and well defined, and is similar to the condition in Cymbospondylus , other shastasaur-grade ichthyosaurs, Callawayia neoscapularis, and Californosaurus perrini , which all possess concave ventromedial margins of the pubis and ischium (Merriam, 1902 , 1908 ; Nicholls & Manabe, 2001 ).

Only BES SC 999 and PIMUZ T 4376 preserve both hindfins (Figs. 2 , 3 ). The hindfins are complete in the holotype, whereas most of the autopodia are missing in the latter specimen. In PIMUZ T 4847, only some proximal elements of the hindfins are preserved. Based on the preserved elements and our reconstruction, the hindlimb is about 70% the length of the forelimb. The hindfin possesses four digits representing primary digits II–V (McGowan & Motani, 2003 ; Shang & Li, 2013 ). Preaxial and postaxial accessory digits are absent, in contrast to Guizhouichthyosaurus tangae , in which a preaxial accessory digit is variably present (Shang & Li, 2013 ). Moreover, in contrast to the forefin, the phalanges in the hindfin are more tightly packed together and constricted in the middle (retaining a rudimentary shaft), showing a condition more similar to Mixosauridae (e.g., Repossi, 1902 ; Brinkman, 2004 ) than to Guizhouichthyosaurus tangae (Shang & Li, 2009 ) and Shonisaurus popularis (Camp, 1980 ), in which the phalanges are suboval to subcircular in outline and lack mid-shaft constrictions.

Femur —Femora are preserved in BES SC 999, PIMUZ T 4376, and PIMUZ T 4847, although in the latter specimen they are incomplete (Fig. 8 E–H). In BES SC 999 the right femur is preserved in dorsal view, whereas the left femur is preserved in ventral view. However, as a result of extreme compression, the preserved cranial and caudal margins of the femora might not precisely correspond to their actual cranial and caudal margins. In PIMUZ T 4376 the right femur is preserved in ventral view, whereas the left femur is preserved in cranial view. In PIMUZ T 4847 the orientation of the femora is unclear.

In dorsal and ventral view, the femur shows concave cranial and caudal margins; despite this, the midshaft is only slightly constricted. The craniocaudal length of the proximal end is shorter than that of the distal end. On the proximal end, well-developed dorsal and ventral processes are present. The dorsal process is positioned cranioproximally, whereas the ventral process is located more centrally (Maxwell et al., 2012 ). Both processes extend for approximately one-third of the femoral proximodistal length. Two distal facets for the tibia and fibula, which are in continuity with each other, can be distinguished at the distal end of the bone. The fibular facet is shorter, faces caudodistally, and is inclined at an angle of > 45° with respect to the proximodistal axis of the femur. The facet for the tibia is larger and faces entirely distally. Anterodistally, the femur forms a distinct flange, also seen in Pessopteryx (Wiman, 1910 ).

In dorsal and ventral view, the femoral shaft of Besanosaurus leptorhynchus looks craniocaudally broader than the femoral shafts of Guanlingsaurus liangae (Sander et al., 2011 ), Shonisaurus popularis (Camp, 1980 ), and Californosaurus perrini (Merriam, 1902 ). Also, in the three latter taxa, the proximal end is proportionally shorter craniocaudally than in Besanosaurus leptorhynchus . Overall, among shastasaurid taxa, the femur of Besanosaurus leptorhynchus is most similar to femur type A of Guizhouichthyosaurus tangae (Shang & Li, 2013 ).

Tibia —Both tibiae are preserved in BES SC 999, PIMUZ T 4376, and PIMUZ T 4847 (Figs. 2 , 3 , and 8 ). In the holotype, the left one is still close to its in vivo position, whereas the right one is markedly dislocated. In PIMUZ T 4376 and PIMUZ T 4847, the tibiae are disarticulated and better preserved in the former.

The proximal end of the tibia is straight in dorsal/ventral view and craniocaudally longer than the convex distal end. The caudalmost portion of the distal end likely contacted the astragalus, as in articulated hindfins of Guizhouicthhyosaurus tangae (Shang & Li, 2013 ). In dorsal and ventral view, the shaft is straight and relatively long, with gently concave cranial and caudal margins. This is in contrast to the condition in Guizhouichthyosaurus tangae (Shang & Li, 2013 ), Guanlingsaurus liangae (Sander et al., 2011 ), Shastasaurus osmonti (Merriam, 1902 ), Shonisaurus popularis (Camp, 1980 ), and Californosaurus perrini (Merriam, 1902 ), in which the tibial shaft is proportionally shorter and thicker, and the anterior margins are deeply concave.

Fibula —Both fibulae are preserved in BES SC 999, PIMUZ T 4376, and PIMUZ T 4847 (Figs. 2 , 3 , and 8 ). Like the tibia, the left fibula is still close to its in vivo position in the holotype.

The proximal end of the fibula is craniocaudally much smaller than the distal one. The facets for the calcaneum and the astragalus are wide, almost equal in size, and in continuity with each other. The separation between the two facets is not well defined, although they are symmetrically inclined at an angle of ~ 45° with respect to the proximodistal axis of the bone. In vivo, the tibia and fibula were likely completely separated from each other, as none of the two bones show facets for mutual articulation.

Overall, the general shape of the fibula of Besanosaurus leptorhynchus is similar to that of Cymbospondylus (Merriam, 1908 ) and most other shastasaur-grade ichthyosaurs (e.g., Merriam, 1902 ; Sander et al., 2011 ; Shang & Li, 2013 ), with the exception of Shonisaurus popularis , in which the fibula is proportionally shorter proximodistally and produces a prominent distal flange (Camp, 1980 ).

Tarsus and metatarsus— BES SC 999 possesses two proximal tarsals: the astragalus and the calcaneum. The presence of ossified tarsals is uncertain in PIMUZ T 4376 due to incomplete preservation of the hindfins. The astragalus is craniocaudally longer than proximodistally tall and much larger than the calcaneum, which is subcircular in outline (Figs. 8 , 9 ). The general shape and proportions of the tarsal bones resemble those of Guizhouichthyosaurus tangae (Shang & Li, 2009 , 2013 ) and Guanlingsaurus liangae (Ji et al., 2013 ; Yin et al., 2000 ), but differ from Shastasaurus osmonti , in which the astragalus is also larger than the calcaneum, but both tarsals are subcircular in outline (Merriam, 1908 ).

3D reconstruction of the pelvic girdle and hindfins of Besanosaurus leptorhynchus based on the CT scans of BES SC 999 in laterofrontal ( A ), frontal ( B ), and dorsal ( C ) view. Shang & Li ( 2013 : fig.  1 ) and McGowan & Motani ( 2003 : fig. 70) were used as references for hindfin reconstruction. Original elements in white; elements reconstructed on the basis of the available material in grey. Scale bars represent 50 cm. Note that the pelvic girdle and hindfin elements were subject to extreme dorsoventral compression during fossilisation and appear much more flattened in the reconstruction than they would be in vivo

In the Besanosaurus leptorhynchus holotype, three elements are identified as distal tarsals (distal tarsals 2–4) and four elements are identified as metatarsals (metatarsals II–V). Distal tarsals 2 and 3 are subcircular in outline and much smaller than the suboval distal carpal 3. Metatarsals II and III possess a rounded anterior margin and a shallow notch on the caudal margin. Metatarsals IV and V are subcircular in outline and do not bear any notches. According to our reconstruction, metatarsal V contacted the distal portion of the calcaneum as in several Triassic ichthyosaurs (e.g., McGowan & Motani, 2003 ). This differs from the condition reported by Shang & Li ( 2009 , 2013 ) for Guizhouichthyosaurus tangae , in which distal tarsal 4 contacts the distal part of the calcaneum and metatarsal V lies in the same row with the other metacarpals.

Pardo-Pérez et al., ( 2020 : fig. 1g, h) reported a case of ankylosis in the hindlimb metapodial elements II and III of BES SC 999. We confirm that a small portion of the caudal margin of metatarsal II is fused to the cranial margin of metatarsal III.

Pedal phalanges —In BES SC 999, the pedal phalanges retain rudimentary shafts, showing an anterior and/or a posterior shallow notch (Fig. 8 A, C ), whereas in PIMUZ T 4376 they are mostly rounded in outline, except for the largest proximal phalanges, which bear anterior notches (Fig.  3 ). These differences between the two specimens are attributed to their different ontogenetic stages.

In BES SC 999, most of the pedal phalanges are preserved in life position, being in close contact or only slightly separated from each other. This provides evidence that, in Besanosaurus leptorhynchus , the pedal phalanges were closely packed and that the relative amount of interphalangeal cartilage was much lower in the hindfin than in the forefin (see above). As a result, the hindfins might have been stiffer than the forefins. This feature contrasts with the condition seen in Guizhouichthyosaurus (Shang & Li, 2009 ), where manual and pedal phalanges show a similar degree of spacing and the pedal phalanges are not preserved in contact with each other. Furthermore, even in large (adult) specimens of Guizhouichthyosaurus (Shang & Li, 2009 , 2013 ), all of the pedal phalanges appear to be rounded. Therefore, the pes of adult Besanosaurus leptorhynchus appears to be more similar to that of Mixosaurus , in which the pedal phalanges retain constricted shafts and are tightly packed (e.g., Brinkmann, 2004 ; Renesto et al., 2020 ; Repossi, 1902 ), than to all other shastasaur-grade ichthyosaurs, in which the pedal phalanges are circular in outline (e.g., Camp, 1980 ; Shang & Li, 2013 ; Yin et al., 2000 ).

Phylogenetic analysis

We updated the scores of Besanosaurus leptorhynchus in the matrix published by Bindellini et al. ( 2021 ) based on our revision of the postcranium (Files S1, S2). The analysis was performed in TNT 1.5 (Goloboff & Catalano, 2016 ) with memory set to hold 99,999 trees; the traditional search option (1000 replications of Wagner trees, TBR branch swapping algorithm with 10 trees saved per replication) was used, followed by an additional round of TBR branch swapping. Bremer support values were calculated by retaining trees suboptimal by 10 steps.

The analysis resulted in 14,480 MPTs of 717 steps (CI 0.361, RI = 0.787). The topology of the majority rule consensus tree is similar to that published by Bindellini et al. ( 2021 ), except for a few differences (for strict consensus, see Fig. S4; for 50% majority rule consensus, see Fig. S5). Therefore, the updated scores from the postcranial skeleton of Besanosaurus leptorhynchus corroborate the results of some previous phylogenetic analyses, in which “shastasauridae” were recovered as a grade and not a clade (e.g., Maisch & Matzke, 2000 ; Sander, 2000 ; Sander et al., 2011 ; Moon, 2019 ; Moon & Stubbs, 2020 ; Sander et al., 2021 ; contra e.g., Ji et al., 2013 , 2016 ; Jiang et al., 2016 ; Motani et al., 2017 ; Huang et al., 2019 ).

Affinities of Besanosaurus with Pessopteryx and Pessosaurus

Among Triassic ichthyosaurs, Besanosaurus leptorhynchus shows some similarities with fossils attributed to Pessopteryx and Pessosaurus from the Early–Middle Triassic of Svalbard (Wiman, 1910 ; Maisch & Matzke, 2000 : 85–86; McGowan & Motani, 2003 : 127–128, 135–136; Maxwell & Kear, 2013 ). The humeri referred to Pessopteryx nisseri are similar to Besanosaurus leptorhynchus , although they do not show a notched anterior margin, and they appear clearly proximodistally longer than craniocaudally wide (e.g., Wiman, 1910 : taf. VIII, figs. 1, 2; G.B. pers. obs. 2021). An exception is PMU 24592b (Wiman, 1910 : taf. VIII, fig. 3; G.B. pers. obs. 2021), which shows a notched anterior margin and proportions more similar to those of BES SC 999.

The femora of Besanosaurus leptorhynchus are also similar to those of Pessopteryx nisseri : the anterodistal process occurs in both taxa but seems to be slightly less prominent in femora originally referred to Pessopteryx (e.g., PMU 24602, 24603; PMUR 1000–1007; G.B. pers. obs. 2021). The proportions of this process vary in other isolated femora from Svalbard, demonstrating a continuous range (e.g., PMU 24602, 24603; PMUR 1000–1007), and possibly indicating some intraspecific variation. PMU 24585 (Wiman, 1910 : taf. VII, fig. 3), a femur attributed to Pessosaurus polaris , was described as being more similar to PIMUZ T 4376 than to BES SC 999; this is due to the fact that in both PIMUZ T 4376 and PMU 24585 an anterodistal process was considered to be missing (McGowan & Motani, 2003 : 128). However, in both specimens the anterodistal portion of the femur is broken and incomplete (G.B. pers. obs. 2021) and therefore the resemblance between the two specimens must be considered an artefact: in both cases the facet for the tibia is incomplete and the anterodistal process is almost completely missing. Furthermore, the fracture is partly filled by plaster in PIMUZ T 4376 (G.B. pers. obs. 2021).

PMU 24584 (PMUR 176 in Wiman, 1910 : taf. VII, fig. 2), a specimen consisting of a coracoid, a radius, a humerus, and a podial element attributed to Pessosaurus polaris , was considered similar to PIMUZ T 4376 by Maisch & Matzke ( 2000 ), who tentatively referred the specimen to Mikadocephalus cf. gracilirostris , a junior synonym of Besanosaurus leptorhynchus (Bindellini et al., 2021 ; McGowan & Motani, 2003 ). The radius of PMU 24584 is proximodistally relatively shorter than those of any other Besanosaurus leptorhynchus specimens examined in this study (craniocaudal/proximodistal length ratio equals 0.7 in PMU 24584; in Besanosaurus leptorhynchus it ranges from 1.03 to 1.12—Table 2 ), showing proportions more similar to those of Shastasaurus osmonti (Merriam, 1902 : pl. 11; ratio equals 0.8). Furthermore, the humerus of PMU 24584 is also relatively shorter proximodistally than that of PIMUZ T 4376 and all other examined specimens of Besanosaurus leptorhynchus (craniocaudal/proximodistal length ratio equals 0.9 in PMU 24584; in Besanosaurus leptorhynchus it ranges from 0.98 to 1.09—Table 1 ) and is slightly more similar in proportions to the humerus of Guanlingsaurus (Ji et al., 2013 : fig. 3; ratio equals 0.82).

Another aspect worth noting is that among the several phalanges attributed to Pessopteryx or Pessosaurus (e.g., Wiman, 1910 : taf. VIII; G.B. pers. obs. 2021) there were no phalanges with retained shafts. The absence of large phalanges with retained shafts in the Svalbard material indicates the likely absence of Besanosaurus leptorhynchus from this fauna.

In conclusion, although the presence of Besanosaurus leptorhynchus and its possible synonymy with Pessopteryx and Pessosaurus was previously proposed, in light of the anatomical observations mentioned above, we do not consider Besanosaurus leptorhynchus as present in the Triassic Svalbard ichthyosaur fauna and do not consider Besanosaurus a possible junior synonym of either of the two taxa (Maisch, 2010 ; Maisch & Matzke, 2000 ; McGowan & Motani, 2003 ). Nonetheless, the similarities between Besanosaurus leptorhynchus and material referred to Pessosaurus and Pessopteryx suggest that large shastasaur-grade ichthyosaurs similar and possibly closely related with Besanosaurus leptorhynchus were already present in the Early–Middle Triassic of Svalbard. More complete material is needed to scrutinize the taxonomy and phylogenetic position of Pessosaurus and Pessopteryx , and to determine whether these two taxa served as ‘waste-basket’ taxa, encompassing isolated material belonging to shastasaur-grade ichthyosaurs, cymbospondylids, mixosaurids, or even omphalosaurids (Qiao et al., 2022 ).

Remarks on forefin and hindfin ossification in Besanosaurus

Xie et al. ( 2020 ) demonstrated that in some odontocete limbs, secondary ossification centres (SOCs) are reduced or absent, contrary to the condition in terrestrial mammals, which results in the autopodial bones becoming widely spaced. The authors suggested that the return of cetaceans to an aquatic environment was associated with a gradual reduction in the size of SOCs in some lineages or even a complete loss in some species. In orcas (Xie et al., 2020 : fig. 4), phalanges in the forefin are short and round, completely lack SOCs, and are separated from each other by a large amount of (fibro-)cartilage and connective tissue. Wide spacing of rounded autopodial elements is also seen in the forefins of Besanosaurus leptorhynchus , but not in the hindlimbs. As in other ichthyosaurs, these marine reptiles did not have secondary ossification centres, and instead, the change to more unified rounded autopodial bone shapes was achieved by loss of perichondral/periosteal bone in the ‘shaft regions’ of these elements (e.g., Caldwell, 1997 ). Because of the wide spacing of the individual elements, we hypothesise they were also set in a (fibro-)cartilaginous rich connective tissue, similar to the one seen in Orcinus orca . The phalanges gradually became more closely packed throughout the evolution of Ichthyosauria, until they became polygonal and tightly packed in both the fore- and hindfins in Parvipelvia (e.g., McGowan & Motani, 2003 ).

Testing the swimming mode of Besanosaurus

To investigate the swimming mode of Besanosaurus leptorhynchus and sympatric ichthyosaurian taxa, we expanded on the body outline analysis originally published by Motani et al. ( 1996 ), as detailed in the Methods section. Anguilliform swimmers show a low H/L ratio and a low fineness ratio and are grouped in the lower left corner of the body outline morphospace, whereas the thunniform swimmers show a high H/L ratio and a high fineness ratio and are clustered in the top right corner (Motani et al., 1996 ).

The resulting body shape morphospace was divided by two lines (a and b), which define four morphospace regions. The ichthyopterygian taxa, in which a dorsal fin has been reported or inferred, occupy the area of the morphospace above line a. These include parvipelvians and Mixosaurus , but also all of the fishes included in the analysis. Basal Ichthyopterygia, Cymbospondylidae, and shastasaur-grade ichthyosaurs occupy the region of the morphospace below line a. Line b divides all those taxa with a caudal fluke (tail height sensu Motani et al., 1996 ) dorsoventrally taller than their body height (on the right), and taxa that have a tail dorsoventrally shorter than their body height (on the left). Parvipelvians and shastasaur-grade ichthyosaurs occupy the area of the morphospace to the right of line b, whereas more basal ichthyopterygians are plotted on the left.

Besanosaurus leptorhynchus falls close to the other shastasaur-grade ichthyosaurs included in this analysis, as well as to Cymbospondylus . The fineness ratio of Besanosaurus leptorhynchus is similar to the one obtained for Cymbospondylus , but the H/L ratio of the caudal fluke is more similar to that of Gualingsaurus. Nonetheless, in Cymbospondylus this ratio might be affected to some extent by the lack of data regarding the presence and the height of a dorsal lobe of the tail fluke. All non-parvipelvian ichthyosaurs fall inside the 95% confidence ellipse fitted to data for 94 species, belonging to 14 families of sharks (Motani et al., 1996 : fig. 2a). Among shastasaur-grade ichthyosaurs included in our analysis, Gualingsaurus liangae and Guizhouichthyosaurus tangae plot inside the carcharhinid ellipse, whereas Besanosaurus leptorhynchus fall just outside of it. The very long tail of Besanosaurus leptorhynchus causes it to plot within the scyliorhinid ellipse, close to Cymbospondylus . Utatsusaurus falls within the scyliorhinid ellipse, and Chaohusaurus geishanensis plots just outside of it. However, the original reconstruction of a specimen of Chaohusaurus chaoxianensis from Motani et al. ( 1996 ) falls inside the scyliorhinid ellipse, i.e., among anguilliform swimmers. Among Triassic ichthyosaurs, solely Mixosaurus falls outside the carcharhinid and selachimorph ellipse, close to odontaspid and sphyrenid sharks, which possess the lowest fin H/L ratio among the fishes included in the dataset of Motani et al. ( 1996 ).

Stenopterygius clusters close to Lamniformes (Carcharhinidae), i.e., carangiform swimmers. A new born Stenopterygius, clusters closer to more anguilliform swimmers . The rest of the parvipelvian ichthyosaurs plot closer to the area occupied by thunniforms, with Ophthalmosaurus clustering closer to tuna than to any other ichthyosaur. On the other hand, Triassic ichthyosaurs appear to cluster among subcarangiform and anguilliform swimmers, with Mixosaurus being almost an outlier: this taxon possesses the highest fineness ratio among Triassic ichthyosaurs (Fig. 10 ).

Graph showing the body shape distribution of selected ichthyopterygians and fishes. Tail fin H/L ratio is fluke height divided by fluke length (x-axis), fineness ratio is body height—excluding the dorsal fin—divided by prefluke length (y-axis). Diagram redrawn from Motani et al. ( 1996 ) with additional taxa plotted (see text, Fig. S1 and Tab. S1 for details). For Californosaurus , Temnodontosaurus , and Eurhinosaurus , “*” designates a reconstruction in which the dorsal lobe of the caudal fluke is 50% the height of the ventral one, “**” designate the reconstruction in which it is 25% of the height of the ventral lobe

Remarks on the swimming style of Besanosaurus , Cymbospondylus , and Mixosaurus

The fineness ratio of Besanosaurus leptorhynchus (updated skeletal reconstruction given in Fig.  11 ; Fig. S7) is more similar to that of Cymbospondylus , which clusters among anguilliform swimmers, than to the rest of the shastasaur-grade ichthyosaurs ( Shonisaurus, Guanlingsaurus, Guizhouichthyosaurus ). However, the inferred tail H/L ratio of Besanosaurus leptorhynchus is more similar to that of Guizhouichthyosaurus than to Cymbospondylus . This indicates that Besanosaurus leptorhynchus had body proportions intermediate between these taxa, with a trunk shape similar to that of Cymbospondylus and a tail more similar to that of shastasaur-grade ichthyosaurs. The inference that Besanosaurus leptorhynchus might have swum in a way intermediate between Cymbospondylus and more derived ichthyosaurs is supported by the relative phylogenetic position of these taxa (e.g., Bindellini et al., 2021 ; Ji et al., 2016 ; Maisch & Matzke, 2000 ; Moon, 2019 ; Moon & Stubbs, 2020 ; Motani et al., 2017 ; Sander et al., 2011 ) and by the morphology and position of the rib facets along the vertebral column. Slijper ( 1936 ) reported the reduction of the rib count and the replacement of sternal and dichocephalous ribs by floating ribs and holocephalous ribs in the early evolution of whales, associating this trend with an increased thoracic flexibility needed by early whales to swim and dive. Furthermore, in Jurassic ichthyosaurs, ribs are dichocephalous cranially and holocephalous caudally and the transition occurs posterior to the 40th centrum (Buchholtz, 2001 ), whereas in Triassic ichthyosaurs dichocephalous ribs are present almost exclusively in the cervical region (e.g., Camp, 1980 ; Fröbisch et al., 2006 ; Merriam, 1902 ; Sander, 1989 ; Shang & Li, 2009 ). Buchholtz ( 2001 ) concluded that dichocephalous ribs have less freedom of movement than holocephalous ones and that the transition point marks the transition from a rigid to a more flexible body region. This hypothesis also supports the idea that Triassic ichthyosaurs were more anguilliform or subcarangiform swimmers, whereas parvipelvians were carangiform and thunniform swimmers.

Full skeletal reconstruction of Besanosaurus leptorhynchus . Size and proportions are based on the holotype BES SC 999. Scale bar equals 1 m. Line drawing by Marco Auditore

Among the ichthyosaurs from the Besano Formation, the dimensions and position of the diapophyses in the dorsal vertebrae of Cymbospondylus buchseri most closely resemble the caudalmost dorsals and cranialmost caudals of Besanosaurus leptorhynchus . These centra are characterised by the presence of small and round diapophyses, that could have granted a greater range of movement to the ribcage. The fact that such morphology appears more cranially in Cymbospondylus than in Besanosaurus leptorhynchus is consistent with a more anguilliform swimming style in Cymbospondylus . In Mixosaurus , a second facet for the articulation of dichocephalous ribs reappears on the sides of the centra close to the pelvis (e.g., Brinkman, 2004 ). This condition, which contrasts with that in Besanosaurus leptorhynchus and Cymbospondylus , could have granted more stiffness to the dorsum. In support of this hypothesis, we point out that Mixosaurus , among Triassic ichthyosaurs, is the only taxon for which a dorsal fin has been reported so far (Renesto et al., 2020 ). This taxon also shares a more similar fineness ratio to that of Carcharodon carcharias and Ophthalmosaurus , than to that of Cymbospondylus and Besanosaurus leptorhynchus . Moreover, Mixosaurus possesses smaller hindfins in comparison to other Triassic taxa—with regard to the forefin/hindfin ratio (Table S1), Mixosaurus (1.88) falls closer to Stenopterygius quadriscissus (1.92) and Ophthalmosaurus icenicus (2.3) than to Besanosaurus leptorhynchus (1.44) and Cymbospondylus petrinus (1.18). Given the phylogenetic position of Mixosaurus (e.g., Bindellini et al., 2021 ; Ji et al., 2016 ; Jiang et al., 2006 ; Motani, 1999 ; this paper), we propose that this taxon, independently and convergently, acquired a combination of morphological adaptations that would later appear in Parvipelvia. These could have granted Mixosaurus a more efficient swimming style (in terms of net cost of locomotion) when compared to the swimming style of the coeval, sympatric and larger Besanosaurus leptorhynchus and Cymbospondylus . Gutarra et al. ( 2019 ) effectively demonstrated that large body sizes, as well as non-anguilliform swimming modes, markedly reduced the net cost of locomotion in ichthyosaurs. Therefore, we hypothesize that Mixosaurus, being much smaller than Cymbospondylus and shastasaur-grade ichthyosaurs and occupying a niche distinct from the two large ichthyosaur taxa from the Besano Formation (Bindellini et al., 2021 ), achieved a more efficient style at its small body size through the evolution of the aforementioned morphological adaptations. Furthermore, a remarkable (unique among ichthyosaurs) increase in the heights of the vertebral centra in the middle portion of the tail in Mixosaurus has been suggested to be an adaptation for a high capability for acceleration (Motani, 1998 ).

None of the three ichthyosaurs known from the Besano Formation have been demonstrated to possess a lunate tail fluke. On the other hand, despite the absence of soft tissue in the caudal peak region of the examined specimens of Besanosaurus leptorhynchus , the presence of a dorsal lobe of the caudal fin may be inferred, based on the recent discoveries concerning Mixosaurus (Renesto et al., 2020 ). Based on the position of the tailbend, the tail of Besanosaurus leptorhynchus likely possessed a markedly heterocercal caudal fluke. A heterocercal tail fluke would have granted greater manoeuverability but would have also resulted in a relatively slower swimming speed (e.g., Thomson & Simanek, 1977 ; Motani, 2002 ; Croft et al., 2019 ). According to Gutarra et al. ( 2019 ), this was compensated in Cymbospondylus and Besanosaurus leptorhynchus by large body size, and in Mixosaurus by the adaptations mentioned above. In particular, in Besanosaurus leptorhynchus, manoeuvrability could have been enhanced by a highly heterocercal tail and relatively long forefins (as suggested for sharks by e.g., Thomson & Simanek, 1977 ). Moreover, good manoeuvrability of the body supports the hunting strategy recently hypothesised for Besanosaurus leptorhynchus , a longirostrine raptorial snap feeder catching prey by rapid and precise movements of the head and neck (Bindellini et al., 2021 ; Fig.  12 ).

Rounded phalanges surrounded by a significant amount of cartilage in the forefins of Besanosaurus leptorhynchus would likely result in long and flexible appendages, useful for better manoeuvring of the anterior half of the body. On the other hand, hindfins with subrectangular and packed phalanges might have been stiffer and steadier. Similarly, long and robust hindfins were suggested to enhance manoeuvrability in Sveltonectes insolitus (Fischer et al., 2011 ). Since the main purpose of the dorsal fin is to stabilize the animal against rolling and yawing (e.g., Lingham-Soliar, Lingham-Soliar, 2005 ; Sanden & Lauder, 2007 ), aside from enhancing manoeuvrability, long forefins and hindfins in Besanosaurus could have compensated for the absence of a dorsal fin (Fig. 12 ).

Artistic reconstruction of Besanosaurus leptorhynchus (based on BES SC 999) catching a Phragmoteuthis . Two individuals of Mixosaurus and a shoal of the ammonoid Ceratites can be seen in the background to the left of Besanosaurus leptorhynchus. Some ammonoids of the genus Serpianites are visible swimming around the large ichthyosaur and a single individual of the same ammonoid is depicted in the foreground on the right, along with other specimens of Phragmoteuthis . Artwork by Alessio Ciaffi

Conclusions

In this work, we described the postcranial anatomy of Besanosaurus leptorhynchus based on four specimens, of which BES SC 999 and PIMUZ T 4376 are remarkably complete. This study and the recent publication of the skull material (Bindellini et al., 2021 ), comprise an extensive and complete revision of this taxon.

Besanosaurus leptorhynchus possesses a peculiar body profile intermediate between Cymbospondylus and some shastasaur-grade ichthyosaurs. The vertebral count consists of 61 presacral centra, at least two sacral vertebrae, and at least 138 caudal vertebrae. The position and the anatomy of the rib facets show characteristics common with both Cymbospondylus and shastasaur-grade ichthyosaurs. The caudal series represents 55% of the length of the whole axial skeleton. The presence of a tailbend that forms an angle of ~ 30° is confirmed and suggests the presence of a heterocercal caudal fluke, more similar to that of shastasaur-grade ichthyosaurs than to that of Cymbospondylus and mixosaurids. Remarkably, the pedal phalanges retain reduced shafts, a feature absent in all other shastasaur-grade ichthyosaurs, but also present in Mixosaurus . Conversely, forefin phalanges are round as in other shastasaur-grade ichthyosaurs. The rounded phalanges in the forefins were likely surrounded by a significant amount of cartilage, likely making them flexible and useful for better manoeuvering of the anterior half of the body. Such an adaptation is consistent with the ecological niche and hunting strategy previously hypothesised for Besanosaurus leptorhynchus . Furthermore, given some similarities in the morphology of the manual phalanges with some modern cetaceans (e.g., orcas, Xie et al., 2020 ), we suggest that in Besanosaurus leptorhynchus , the rounded profile of the forefin elements is achieved by partial loss of perichondral/periosteal bone in the shaft regions. Moreover, individual elements are hypothesised to be set in a (fibro-)cartilaginous rich connective tissue, which would explain their broad spacing.

After updating the phylogenetic scores of Besanosaurus leptorhynchus and testing its phylogenetic position we conclude that this taxon represents the earliest diverging member of Merriamosauria. Furthermore, shastasaurs are found to be a grade and not a monophyletic group, corroborating the previous results of Bindellini et al., ( 2021 ).

To test the swimming capabilities of Besanosaurus leptorhynchus we expanded on the body outline analysis of Motani et al., ( 1996 ) by adding 27 ichthyosaurian and fish taxa. This allowed for increasing the representation of the phylogenetic diversity and swimming styles in the dataset. Besanosaurus leptorhynchus plots in between anguilliform swimmers, such as Cymbospondylus , and shastasaur-grade ichthyosaurs. This result is supported by the anatomy reported in the description and by the recovered phylogenetic position . We also propose that Mixosaurus , independently and convergently, evolved a combination of adaptations that would later appear in Parvipelvia, such as a relatively rigid trunk, smaller hindfins, and a dorsal fin. These adaptations could have granted Mixosaurus a more efficient (in terms of net cost of locomotion) swimming style, when compared to the swimming styles of the larger Triassic ichthyosaurs and were likely related to the small body size of this taxon. Different swimming styles for Cymbospondylus, Mixosaurus, and Besanosaurus leptorhynchus are supported by the suggested niche partitioning of the three taxa from the Besano basin, as well as by their different anatomy, body proportions, and dimensions.

Previous authors have suggested the possibility that Besanosaurus is synonymous with ichthyosaur taxa described from the Triassic of the Svalbard archipelago. After comparing Besanosaurus leptorhynchus , Pessopteryx , and Pessosaurus we conclude that Besanosaurus leptorhynchus is not a junior synonym of either of the two taxa.

In summary, this manuscript completes the morphological and taxonomic revision of Besanosaurus leptorhynchus , being complementary to the previous work on this ichthyosaur (Bindellini et al., 2021 ; Dal Sasso & Pinna, 1996 ). Research on ontogenetic variation and the foetal remains inside the holotype specimen is still ongoing.

Availability of data and materials

All data generated or analysed during this study are included in this published article and its supplementary information files. The described specimens are available for study at the PIMUZ and MSNM.

Abbreviations

Museo di Storia Naturale di Milano, Milan, Italy

Department of Paleontology, University of Zurich, Zurich, Switzerland

Museum of Evolution, Uppsala University, Uppsala, Sweden

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Acknowledgements

We thank the volunteers of the former “Gruppo paleontologico di Besano”, who unearthed the holotype of Besanosaurus leptorhynchus , and many other exceptional fossils. We also thank D. Affer, F. Fogliazza and L. Magnoni (MSNM), C. Egli (PIMUZ), and B. Riss (PIMUZ) for preparation of the specimens; M. Auditore for anatomical drawings; A. Ciaffi for the artwork; L. Forzenigo, C. Bonelli, and G. Terribile (Fondazione IRCCS “Cà Granda” Ospedale Maggiore Policlinico di Milano) for CT scanning the holotype of Besanosaurus leptorhynchus ; the “Ministero della Cultura” and the “Soprintendenza Archeologia, Belle Arti e Paesaggio delle province di Como, Lecco, Monza-Brianza, Pavia, Sondrio e Varese” for permissions. For 3D-scanning the holotype of Besanosaurus leptorhynchus , we thank M. Merella and F. Nobile (Università di Pisa). For access to key specimens in museum collections, we thank C. Klug (PIMUZ), B. P. Kear (PMU), E. E. Maxwell (SMNS) and R. B. Hauff (Urweltmuseum Hauff, Holzmaden). We also thank M. Auditore, M. Balini, A. Crasti, B. P. Kear, S. Maganuco, and G. Teruzzi, for helpful discussions and the Willi Hennig Society for making TNT 1.5 freely available. Finally, we thank editor Daniel Marty and three anonymous reviewers for their feedback, which helped us to improve our manuscript.

This paper is part of a Ph.D. project (GB) focusing on the Besano Formation fossil fauna, led by the Università Statale di Milano (M. Balini) in agreement with the Museo di Storia Naturale di Milano (C. Dal Sasso). ASW was supported by the International Postdoctoral Exchange Fellowship Programme from the Chinese Postdoctoral Science Foundation, grants from the National Natural Science Foundation of China awarded to ASW (42202006) and Jun Liu (41772003, 42172026), and the Bekker Program of the Polish National Agency for Academic Exchange (BPN/BEK/2022/1/00194). TMS acknowledges support by the Swiss National Science Foundation (Grant No. 31003A_179401).

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Dipartimento di Scienze della Terra “Ardito Desio”, Università degli Studi di Milano, Milan, Italy

Gabriele Bindellini

Dipartimento di Scienze della Terra, Sapienza Università di Roma, Rome, Italy

Department of Earth Sciences, University of Cambridge, Cambridge, UK

Andrzej S. Wolniewicz

School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, China

Institute of Paleobiology, Polish Academy of Sciences, Warsaw, Poland

Staatliches Museum Für Naturkunde Stuttgart, Stuttgart, Germany

Feiko Miedema

Sezione di Paleontologia dei Vertebrati, Museo di Storia Naturale di Milano, Milan, Italy

Cristiano Dal Sasso

Paläontologisches Institut, Universität Zürich, Zurich, Switzerland

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GB, CDS and TMS designed the research. GB prepared all figures and tables, segmented and visualised CT data and performed the body shape analysis. All authors analysed and interpreted the anatomical data. GB wrote the manuscript with contributions from other authors. All authors read and approved the final manuscript.

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Correspondence to Gabriele Bindellini .

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Supplementary Information

13358_2024_330_moesm1_esm.zip.

Supplementary material 1: Fig. S1 Close-up of the ribcage of BES SC 999, the holotype of Besanosaurus leptorhynchus (caudal right quarter; slab 26 following the numbering in Dal Sasso & Pinna, 1996 ). Scale bar equals 10 cm. Fig. S2 Close-up of the cervico-dorsal region and shoulder girdle of BES SC 999, the holotype of Besanosaurus leptorhynchus . Scale bar equals 10 cm. Fig. S3 Close-up of the interclavicle of Besanosaurus leptorhynchus (PIMUZ T 4376). Scale bar equals 1 cm. Fig. S4 Strict consensus tree of 14,480 most parsimonious trees of 717 steps (CI 0.361, RI = 0.787). Numbers indicate Bremer support values obtained from parsimony analysis of the phylogenetic matrix in File S1. Fig. S5 Majority rule consensus of 14,480 most parsimonious trees of 717 steps (CI 0.361, RI = 0.787), obtained from parsimony analysis of the phylogenetic matrix in File S1. Note that ‘shastasaurids’ are recovered as a grade at the base of Merriamosauria. Percentages of trees in which particular clades are recovered are reported for each node. Fig. S6 Ichthyosaur and fish silhouettes used as measurement sources for the body shape analysis. Silhouettes of Salmo , Gadus , Scomber , Thunnus and Carcharodon are based on those available at fisheries.noaa.gov. Fig. S7 High-resolution version of Fig. 11 . Full skeletal reconstruction of Besanosaurus leptorhynchus . Size and proportions are based on the holotype BES SC 999. Scale bar equals 1 meter. Line drawing by Marco Auditore. Table S1. Ichthyopterygian and fish measurements taken from the silhouettes in Fig. 10 . Lengths and heights are given in cm.

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Bindellini, G., Wolniewicz, A.S., Miedema, F. et al. Postcranial anatomy of Besanosaurus leptorhynchus (Reptilia: Ichthyosauria) from the Middle Triassic Besano Formation of Monte San Giorgio (Italy/Switzerland), with implications for reconstructing the swimming styles of Triassic ichthyosaurs. Swiss J Palaeontol 143 , 32 (2024). https://doi.org/10.1186/s13358-024-00330-9

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Received : 17 December 2023

Accepted : 13 August 2024

Published : 10 September 2024

DOI : https://doi.org/10.1186/s13358-024-00330-9

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• Ichthyosauria
• Shastasauridae
• Middle Triassic
• Besano Formation
• Monte San Giorgio
• Postcranial anatomy
• Swimming style
• Marine reptiles

How to Finish All Your Missing Assignments Fast; 8 Useful Tips

When you do not submit or complete assignments on time you are faced with the challenge of missing assignments. It can be hard to keep track of all your missing assignments when they pile up but don’t worry.

First, talk with your teachers about the assignments you failed to submit and ask for a deadline extension. Then, make a plan for how to handle your work, putting the most important tasks first. Take breaks, treat yourself, and keep a good attitude to get more done. It’s not easy to make up for the schoolwork you missed, but if you’re organized and have a plan, you’ll be better able to handle whatever comes your way.

It is a daunting situation, and without the right approach, you may end up not finishing your missing assignments which will affect your overall grade. Here are critical steps that can help you finish all your missing assignments fast.

1.   Create a list of all missing assignments

When working on missing assignments, you are more likely to pick the easier assignment first and forget about the tough assignments. Making a list of all your assignments helps to make sure you complete all missing assignments.

List all the missing assignments that need to be done; even if you have to re-read notes, all these tasks must be included in the list. Tick off the tasks after completion to keep you motivated.

2.   Create a detailed timetable

A timetable helps you plan your tasks. Assign all your missing assignments time. Schedule more time for the tough assignments. Remember you are on a deadline, so whatever time you estimate an activity might take, reduce it by at least 5 to 10 minutes. You have to be ruthless and, at the same time, realistic when coming up with a timetable.

3.   Gather all assignment materials

After listing all the missing assignments, you will have an idea of all the required materials. You must gather all the necessary tools, such as laptops and writing materials. By doing this, you ensure that you will not have to take breaks now and then to fetch something leading to time wastage. If you are the type of person who concentrates better on music in the background, this can be a great time to choose a studying playlist.

4.   Switch off your devices

You must turn off all the gadgets not needed to do the assignments. These may include phones and tablets. You need to find a place with minimal distraction to enable you fully concentrate on the task at hand.

Being destructed will cost you time which could have been used to finish your missing assignments. Therefore, you can choose to keep your devices in a different room and only use them when you are on break. You can use one of the breaks already programmed to check on your social media.

5.   Ask for Assignment help online

If you’re thinking “I need help with my missing assignments” and want to finish homework fast, don’t avoid getting help. There are fast writers online who will help you with your assignments – for a small price of course.

Remember that your mental health has a big effect on how much you get done. No matter how hard you try, you won’t be able to finish your assignment faster if you are tired or stressed out. Assignment help experts will relieve you of your missing assignments stress.

6.   Reward yourself after finishing a missing assignment

Doing assignments may be challenging. Our brains work better when there is a possibility of getting a reward. Rewarding yourself after finishing each assignment will motivate you to continue and improve your speed.

These rewards can be a few minutes of rest, eating a snack, playing games, or spending some time on social media. These rewards should be manageable, they should not be activities that will take much of your time.

7.   Avoid unnecessary breaks

Breaks are very important when doing any task, but you need to be disciplined and take breaks only when necessary to avoid wasting time. The best way to do this is by working in short sprints and taking at most a 5-minute break.

Remember, it is also not advisable to work continuously without a break. Your mind will be exhausted, and you will take longer to complete simple tasks.

To ensure you are disciplined, you need to have punishments in place if you don’t achieve your target. You can punish yourself by taking away break privileges when a task is not done as allocated.

8.   Stay positive and remember what is at stake

Apart from following these steps, the most important step to finishing all your missing assignments is having a positive mindset. You must remember what is at stake, which in this case, is your academic achievement. Having this in mind will act as a form of motivational tool whenever things seem impossible.

Is it bad to have missing assignments in college?

Yes, it is bad to have incomplete assignments. You can skip some assignments without getting into trouble with the faculty, but you will lose some credits. Some lecturers are lenient and will award you partial credit for late submission of assignments, while others will give you nothing. When you miss assignments and are in an upper-division class, be sure your grades will be negatively impacted. You may not get into trouble with the faculty for missing one or two assignments, but your grades might be affected in the long run.

Do missing assignments affect your GPA?

Yes, missing assignments do affect your GPA. Missing assignments are usually given low or 0 marks which negatively impacts the grade, which is not a good thing for the student. You must maintain a GPA of 2.8 and above to have a good academic transcript. To remain competitive with the higher percentile range of students, you must have a 3.2 and above GPA score.

Can a professor drop you from a class for missing assignments?

Generally, a professor cannot drop you from a class because of missing assignments. However, this will also depend on your institution and its policy regarding missing assignments. Some lecturers are usually lenient and will pardon you for missing a few assignments, while others are stricter.

If you have any concerns about missing assignments, it is important to talk to your lecturer and understand their expectations and policies regarding missing assignments. If you are interested in getting the best results, you can contact your professor with genuine reasons why you missed the assignments and they might agree to give you partial credit that will assist in boosting your final grade.

Can I complete all my missing assignments in a day?

Yes, you can complete all missing assignments in a day. However, it will depend on the type and quantity of assignments you have. In most cases, it will be better to ask for more time instead of producing sub-standard work because of time.

Completing all missing assignments in a day will also require you to devise a good plan and implement it. You will have to stay away from any disruptions that may hinder your progress. Prior planning and communication with your lecturer will help you avoid situations whereby you have to complete a number of missing assignments within a day. You can ask for assignment help online if overwhelmed by deadlines.

Do missing assignments show up on transcripts?

No, missing assignments do not appear in your transcript; they only reduce your grades. Unlike cheating, missing assignments only affect total grades; therefore, it is better to have unsubmitted assignments than receive an “F” because of cheating. The only issue you will have on your transcript due to missing assignments is your GPA.

Can you graduate with missing assignments?

No, you cannot pass a class with missing assignments; therefore, you cannot graduate with incomplete assignments. To complete a course, some different assignments and tasks need to be completed, and failure to complete assignments will greatly affect your overall score.

Therefore, it is critical for a student to ensure that all assignments are completed and preferably on time. However, depending on the institution, you can graduate if the missing assignment didn’t greatly affect your final score.

Can a professor fail you for missing one assignment?

Not really, missing assignments will only impact your grade, and the lecturer has nothing to do with it. Most lecturers deal with several students and do not have time to deal with a particular student’s missing assignment. It is the responsibility of a student to make sure that all the assignments are completed. However, there are lecturers teaching units with few students; such lecturers have the time to follow up on individual students’ missing assignments. You need to know that even the lecturers that follow up on missing assignments will still deduct credit for a late submission.

It is completely the student’s responsibility to ensure no missing assignments. Professors do not fail students because of missing assignments because missing an assignment does not necessarily mean the student is performing badly; it might be because the student had a legitimate reason for not doing that assignment.

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