Batoid or Squatina Vertebra?

[The Jersey Devil]

Hey everyone,

I would like your opinion on this interesting vertebra (from the NJ Late Cretaceous). I identified it a long time ago as a first cervical vertebra from either a ray or an angel shark. An expert looked at some pictures and thinks it is a batoid first cervical vertebra. Sorry about the picture quality, these are old photos. Thanks for any help!

[Carl]

I've only ever heard those called Squatina vertebrae but I've never seen any justification as to why they can't be some other chondrichthyan.

[The Jersey Devil]

14 hours ago, Carl said:

I've only ever heard those called Squatina vertebrae but I've never seen any justification as to why they can't be some other chondrichthyan.

 

Do you think there is a way to distinguish between Squatina and Batoid verts? I always thought that angel shark verts had a smaller anterior face than posterior face compared to ray verts. This vert is a bit different though.

[Carl]

41 minutes ago, josephstrizhak said:

 

Do you think there is a way to distinguish between Squatina and Batoid verts? I always thought that angel shark verts had a smaller anterior face than posterior face compared to ray verts. This vert is a bit different though.

I suspect there is but I've come across nothing in decades of working on this fauna.

[MarcoSr]

15 hours ago, Carl said:

I've only ever heard those called Squatina vertebrae but I've never seen any justification as to why they can't be some other chondrichthyan.

 

I agree with Carl that I have only seen a vertebra like yours "called Squatina vertebrae but I've never seen any justification as to why they can't be some other chondrichthyan."  It is unfortunate that so little is written on fossil shark and ray vertebrae.  I have thousands of shark and ray fossil vertebrae from an Eocene site in Virginia and have tried for years to get researchers to look at them.  I haven't found any interest at all.  I've only been able to find one paper on modern shark vertebrae (identifying modern shark vertebrae found at archaeological sites) and that author wasn't interested either.  I've heard that the vertebrae aren't really diagnostic enough to merit an extensive study.  I don't really agree with that.  I could definitely group a good number of the ones that I have and I believe that the vertebrae of at least certain genera/species are diagnostic.

 

Marco Sr.

[The Jersey Devil]

23 minutes ago, MarcoSr said:

 

I agree with Carl that I have only seen a vertebra like yours "called Squatina vertebrae but I've never seen any justification as to why they can't be some other chondrichthyan."  It is unfortunate that so little is written on fossil shark and ray vertebrae.  I have thousands of shark and ray fossil vertebrae from an Eocene site in Virginia and have tried for years to get researchers to look at them.  I haven't found any interest at all.  I've only been able to find one paper on modern shark vertebrae (identifying modern shark vertebrae found at archaeological sites) and that author wasn't interested either.  I've heard that the vertebrae aren't really diagnostic enough to merit an extensive study.  I don't really agree with that.  I could definitely group a good number of the ones that I have and I believe that the vertebrae of at least certain genera/species are diagnostic.

 

Marco Sr.

 

Hey Marco Sr.,

Thanks for the info. I don't know if this will help, but here is a more usual vertebra from a batoid/Squatina with the cartilage attached. I found many vertebrae that look similar to these, but do not have cartilage attached. Does that mean the only difference between the verts with cartilage and verts without cartilage is that the ones with cartilage are simply better preserved? Is there a way to determine what creature(s) these vertebrae are coming from by examining modern Squatinas and various batoids?

Thanks,

Joseph

[non-remanié]

Carl, the Frankstown paper refers them to batoid.   I think an important study to differentiate would include figuring out all the places where vertebrae with attached cartilage like this are found.  Oddly the only 2 sites I can come up with are the exact same age, Frankstown and the NJ brooks.   Does anyone know of other locations?  

[MarcoSr]

2 hours ago, josephstrizhak said:

 

Hey Marco Sr.,

Thanks for the info. I don't know if this will help, but here is a more usual vertebra from a batoid/Squatina with the cartilage attached. I found many vertebrae that look similar to these, but do not have cartilage attached. Does that mean the only difference between the verts with cartilage and verts without cartilage is that the ones with cartilage are simply better preserved? Is there a way to determine what creature(s) these vertebrae are coming from by examining modern Squatinas and various batoids?

Thanks,

Joseph

 

 

 

Unfortunately I can't answer your first question for sure but your specimens in the new pictures look more like the ray specimens shown in the Manning, Dockery 1992 paper that Steve references:

 

 

 

EDIT: Your first specimen in this post looks more like the Squatina vertebra shown below in Kent 1994:

 

 

 

Although I haven't found papers dealing with just fossil vertebrae, there are a number of papers that show vertebrae that were found associated with teeth etc. that helps identify the vertebrae to a genus/species.  I've seen squatina, cetorhinus, pristis etc. vertebrae depicted in various papers over the years but truthfully no longer remember which papers I saw them in.  Finding vertebrae in one of these papers like the ones above that resemble what you are finding would be the best way to try to identify what you have but it can be like looking for a needle in a haystack to find the applicable papers.

 

 

With respect to your second question, I strongly believe that you need to understand extant sharks and rays to help understand the fossil ones.  Looking at extant ray vertebrae would give you some idea if there are extant ray species that have vertebrae similar to Squatina which might answer your questions.  But to do that you would need to go to a museum with an extant shark and ray vertebrae collection unless there are pictures of the museum's vertebrae collection out on the web somewhere.  Dr Weems who I work with a lot goes to the Smithsonian all the time to look at their extant fish collection when he is trying to id a fish fossil specimen that he hasn't seen before.  If he finds a close extant match then he does a paper search on applicable genera to see if there is anything written up on fossil specimens that might be similar.  However there is at least 65 million years between your specimens and extant species so a lot could have changed over that time period.  Species back then that may have had very similar vertebrae to Squatina may now be extinct.  On the other hand some genera have changed little over millions of years.

 

The below link is to the only extant shark vertebrae paper that I'm aware of.

 

https://www.academia.edu/5653950/A_Guide_to_Identifying_Shark_Centra_from_Southeastern_Archaeological_Sites_Kozuch_and_Fitzgerald_1989?auto=download

 

Marco Sr.

 

 

 

[Al Dente]

Here's some Oligocene Squatina centra from Belgium from "A partial braincase and other skeletal remains of Oligocene angel sharks from northwest Belgium". The second photo are some centra from a modern Squatina that I collected from North Carolina.

[The Jersey Devil]

1 hour ago, MarcoSr said:

EDIT: Your first specimen in this post looks more like the Squatina vertebra shown below in Kent 1994:

 

 

That's interesting. I used to guess that the anterior face was smaller than the posterior face in angel shark verts based on my own specimens. Although based on the specimens that @Al Dente posted, I guess the oligocene and modern verts have an anterior face and posterior face of the same size. Thanks for the match up for the first vert in the post. The second vert also has a smaller anterior face compared to its posterior face. 

[The Jersey Devil]

@MarcoSr Would you say that these attached pics are also of a Squatina hassei vert? It is also from the NJ Late Cretaceous just like the other two verts and has a smaller anterior face than posterior face. Like the second vert I posted, it resembles the vertebra in figure A from the paper about the oligocene of Belgium that @Al Dente posted.

 

Thanks a lot everyone,

Joseph

 

[Carl]

3 hours ago, non-remanié said:

Carl, the Frankstown paper refers them to batoid.   I think an important study to differentiate would include figuring out all the places where vertebrae with attached cartilage like this are found.  Oddly the only 2 sites I can come up with are the exact same age, Frankstown and the NJ brooks.   Does anyone know of other locations?  

Thanks for the reminder, Doc!

[MarcoSr]

3 hours ago, josephstrizhak said:

@MarcoSr Would you say that these attached pics are also of a Squatina hassei vert? It is also from the NJ Late Cretaceous just like the other two verts and has a smaller anterior face than posterior face. Like the second vert I posted, it resembles the vertebra in figure A from the paper about the oligocene of Belgium that @Al Dente posted.

 

Thanks a lot everyone,

Joseph

 

 

There are currently 20 named extant Squatina species.  Eric showed extant vertebrae from one of twenty Squatina species.  First how much vertebrae variation is there within a species?  Second how much vertebrae variation is there among the twenty named species?  Without knowing the answers to these two questions it is difficult to generalize that all extant Squatina vertebrae are all similar to the ones that Eric showed even though this may in fact be true.  Also are there extant rays that have very similar vertebrae?  These same questions apply to fossil vertebrae.  Also are the identifications made by Manning, Kent and in Eric’s paper all correct?  I tend to trust much more vertebrae ids when the vertebrae were found in association with other identifiable parts of the specimen like in Eric’s paper.  My bottom line is that with the current state of published data on vertebrae it is speculative to try to get to a 100% certain id.  Unfortunately you may have to say that your specimen looks like Squatina but it could be ray.  I get really frustrated when I can’t id a lot of my shark teeth 100% to a specific species.  But with a lot of the teeth that I have, one species can be the most likely but there still are other possibilities.

 

Marco Sr.

[The Jersey Devil]

3 hours ago, MarcoSr said:

There are currently 20 named extant Squatina species.  Eric showed extant vertebrae from one of twenty Squatina species.  First how much vertebrae variation is there within a species?  Second how much vertebrae variation is there among the twenty named species?  Without knowing the answers to these two questions it is difficult to generalize that all extant Squatina vertebrae are all similar to the ones that Eric showed even though this may in fact be true.  Also are there extant rays that have very similar vertebrae?  These same questions apply to fossil vertebrae.  Also are the identifications made by Manning, Kent and in Eric’s paper all correct?  I tend to trust much more vertebrae ids when the vertebrae were found in association with other identifiable parts of the specimen like in Eric’s paper.  My bottom line is that with the current state of published data on vertebrae it is speculative to try to get to a 100% certain id.  Unfortunately you may have to say that your specimen looks like Squatina but it could be ray.  I get really frustrated when I can’t id a lot of my shark teeth 100% to a specific species.  But with a lot of the teeth that I have, one species can be the most likely but there still are other possibilities.

 

 

 

Marco Sr.

 

 

That definitely makes sense. I was hoping it would be possible to distinguish between them, but I guess you can't narrow it down further at the moment. Thanks for your info.