Scyliorhinoid Shark Vertebra

[Shellseeker]

I was out hunting the Peace River yesterday,  spent about 3 hours each at 2 locations,

I thought my 1st large (2 inch) Kentriodontae tooth was the prize,  but after looking close, that shark vert is a pretty nice find also...

 

This Vert is 8.5 x 20 mm diameter on the back ?? edge  and 8.5 x 23 mm diameter on the front edge.  Is this normal and does it tell us anything... like where the vert is positioned in the shark?

 

Scyliorhinoid  .. Catshark ??? Have I been finding their teeth in the Peace River...? 

 

What are those marks on the very inner core of the Vert ?

 

Is the hole in the center natural or due to erosion, age, damage ?

 

Ken,  @digit... you know about small Florida sharks ..  What can you tell me about this Vert.....

[Fin Lover]

I have found 2 since I've been hunting and only 1 has the hole all the way through. My larger one also has marks in the center, but I had never even noticed them.

[Fin Lover]

Sorry about the bad pics. Here is one using a different phone.

[Fin Lover]

Let's try that again. User error.

[Shellseeker]

46 minutes ago, Fin Lover said:

I have found 2 since I've been hunting and only 1 has the hole all the way through. My larger one also has marks in the center, but I had never even noticed them.

Thanks for the response and photos. I am very curious and try to make each find a discovery of new knowledge.  

I have my niece and her husband visiting over the weekend, fossils are a normal topic and after I told him what I had found when I first started, he naturally asked what so many ask. "How did you know what you were finding".

I told him the truth:  I didn't  know what I was finding,  but I learned over time by asking questions and doing research.  My motto has always been:  Ask a lot of questions, even dumb ones. With the help of my friends,  I will (slowly) figure it out. 

You and I are going to find out what those marks are....

Our Vertebra are from Scyliorhinoid type sharks and appear to have no septa.  What are a few of the more common Sharks that could produce such vertebra in the South Carolina or Florida Late Miocene?

 

@Al Dente @MarcoSr @siteseer @Northern Sharks @Harry Pristis

[Fin Lover]

It's funny that you mentioned this on the vertebrae post. The larger vertebrae is the first thing I ever found at the beach and I had no idea what it was. It was so perfectly crafted that I just knew it had to be man-made. Luckily, my husband recognized that it was "something" due to the concentric rings, and stuck it in his pocket. I look forward to learning.

[Al Dente]

9 hours ago, Shellseeker said:

This Vert is 8.5 x 20 mm diameter on the back ?? edge  and 8.5 x 23 mm diameter on the front edge.  Is this normal and does it tell us anything... like where the vert is positioned in the shark?

This centrum has a lot of erosion on one side. I don’t know the species but probably some type of Carcharhiniforme.

[Northern Sharks]

44 minutes ago, Al Dente said:

This centrum has a lot of erosion on one side. I don’t know the species but probably some type of Carcharhiniforme.

I was going to say the same thing. Bull, tiger, Hemi, lemon, hammerhead etc. are all potential candidates.

[MarcoSr]

11 hours ago, Shellseeker said:

This Vert is 8.5 x 20 mm diameter on the back ?? edge  and 8.5 x 23 mm diameter on the front edge.  Is this normal and does it tell us anything... like where the vert is positioned in the shark?

 

Scyliorhinoid  .. Catshark ??? Have I been finding their teeth in the Peace River...? 

 

What are those marks on the very inner core of the Vert ?

 

Is the hole in the center natural or due to erosion, age, damage ?

 

The vertebra size seems too large for a catshark.

 

I'm not sure what the marks are.  I haven't seen marks like that before.

 

Sharks have an embryonic stage where a notochord is present, but then during development in the womb, this structure is replaced with a spine.  The remnants of this notochord become the nucleus pulposus, a jelly-like center of intervertebral discs.  This doesn’t fossilize, so you have a hole in the very center of the shark centra. The size of this hole in relation to the centra overall size helps determine the size of the shark at birth according to a researcher who is currently studying thousands of shark centra which I donated.  So all shark centra have this hole, but some are extremely small or get filled in with hard matrix.

 

Marco Sr.

[MarcoSr]

7 hours ago, Shellseeker said:

Our Vertebra are from Scyliorhinoid type sharks and appear to have no septa.  What are a few of the more common Sharks that could produce such vertebra in the South Carolina or Florida Late Miocene?

 

@Al Dente @MarcoSr @siteseer @Northern Sharks @Harry Pristis

 

Check out my post at the below link, which shows a good number of shark centra from different extant species from Southeastern Archaeological Sites:

 

http://www.thefossilforum.com/index.php?/topic/107080-insane-sc-fossil-hunt/page/2/&tab=comments#comment-1187519

 

Marco Sr.

[Shellseeker]

2 hours ago, Northern Sharks said:

I was going to say the same thing. Bull, tiger, Hemi, lemon, hammerhead etc. are all potential candidates.

In the Peace River, the most common shark teeth are; Lemon, Dusky, Bull, Hemi, Tiger  Hammerhead,  making up 80-90% of all small shark teeth finds...

I went down a wrong path trying to figure this out... I thought that Scyliorhinoid type sharks are catsharks and the above common species are not catsharks... more likely Requiem sharks.  Where did I go wrong?

As far as I know,the only Catshark tooth I have found is Nurse shark and they are tiny.

52 minutes ago, MarcoSr said:

Check out my post at the below link, which shows a good number of shark centra from different extant species from Southeastern Archaeological Sites:

This is going to take a while to understand... Looks like a great post.  But I have company and it is Sunday morning...  Going to Breakfast..  Jack

[digit]

11 hours ago, Shellseeker said:

Scyliorhinoid  .. Catshark ??? Have I been finding their teeth in the Peace River...?

Likely not. I've found catshark (Scyliorhinidae) teeth from Cookiecutter Creek and the Montbrook site. All have been found while picking micro-matrix as they tend to be quite tiny.

 

 

12 hours ago, Shellseeker said:

Ken,  @digit... you know about small Florida sharks ..  What can you tell me about this Vert.....

The lamnoid vert are distinguished by the large number of septa running (thin ridges) through the vert as seen from the side. The larger slots are where the cartilaginous neural and haemal arches would fit in on the top and bottom of the vert. The verts that are smooth around the side (except for the slots) are called scyliorhiniform which is likely an artifact of when they were first named (though I cannot support that assertion without some research). The catshark family (Scyliorhinidae) are sister to the Carcharhinidae, Hemigaleidae, and Sphyrnidae all under the order Carcharhiniformes. The verts we find in the Peace River likely come from Carcharhinidae (various Carcharhinus species), Hemigaleidae (Hemipristis serra), and Sphyrnidae (Sphyrna species) and likely no species of Scyliorhinidae so the name is deceiving (or at best confusing). I tend to call shark verts carcharhiniform or lamniform instead.

 

 

Cheers.

 

-Ken

[digit]

22 minutes ago, Shellseeker said:

As far as I know,the only Catshark tooth I have found is Nurse shark and they are tiny.

Despite the resemblance to catsharks, nurse sharks are in the order Orectolobiformes (carpet sharks) along with the huge Whale Shark (Rhincodon typus).

 

 

Cheers.

 

-Ken

[Shellseeker]

23 hours ago, Shellseeker said:

This Vert is 8.5 x 20 mm diameter on the back ?? edge  and 8.5 x 23 mm diameter on the front edge.  Is this normal and does it tell us anything... like where the vert is positioned in the shark?

 

Scyliorhinoid  .. Catshark ??? Have I been finding their teeth in the Peace River...? 

 

What are those marks on the very inner core of the Vert ?

 

Is the hole in the center natural or due to erosion, age, damage ?

I felt I should go back over my questions with summarized answers.

The non_symectric vert would be due to post fossilization wear and tear,  Also the size of both the verts and septa will vary based on the position of the vert within the shark's backbone..

 

The use of the word "Scyliorhinoid " is an unfortunate term to describe a class of shark vertebrae because it is also used as a term to describe a class of sharks.. The word adds confusion rather than clarity.

 

If @MarcoSr with the thousands of shark verts he has seen,  does does not recognize and has never seen the marks on the inter centrum of the Verts I and Fin Lover found,  then those marks must be post _ fossilization and/or some what unique to the organisms in the environment where they were found.

 

The hole is the center of shark verts is natural but may be filled by post fossilization matrix.

 

The research paper on extant shark centra "A Guide to Identifying Shark Centra from Southeastern Archaeological Sites" Kozuch and Fitzgerald 1989. is an easy and good read on the issues in connecting fossil shark vertebra with a specific species of shark. 

 

It allows me to say that the sharks whose verts most resemble the vertebra I found are Bull, Dusky and Sandbar..... which are very common fossils anywhere in the Peace River.

 

Thank to all who responded and helped me to better understand the possibilities for this shark vertebra.  Jack

 

 

[Fin Lover]

Yes, thank you everyone for such helpful information!

 

Jack, I found two more today, both of which have the holes filled in. I don't see the marks on these that we saw on our other ones. But, I'm loving the colors... amazing how much difference there is 30 miles from the beach.