Teeth from Aguja formation

[gturner333]

I obtained some matrix from the Aguja formation, which is late Cretaceous, from Brewster, County, Texas. I have been finding all kinds of good stuff, but will start with the following. The first two pics are from what I believe to be a therapod - maybe Tyranasaurid? There are approx. 5 serrations per mm. The next two are of an unidentified tooth. The last is a group photo of what may be Champsosaurus teeth? The hash marks are 1mm. Any ideas?

[Darktooth]

Can't help with ID, but I really like the first tooth. Maybe @Troodon can help.

[ynot]

The group shot looks like shark teeth with no root.

Can We see other angles of them?

Would like to see end shots of the other two also.

[StevenJD]

First tooth looks like it could be dromaeosaurid.   

The second tooth looks like it could be a shark tooth without a root. 

The group of teeth are champsosaurus.

[Anomotodon]

59 minutes ago, gturner333 said:

 

These teeth are NOT champsosaur, as is widely thought. Champsosaur teeth are also tiny, but they have typical reptilian features - pulpar cavity, thick enamel, they are also very thin and recurved (like some crocodile teeth). Instead these teeth belong to an amiid bony fish Melvius thomasi.

[gturner333]

Interesting. I'm not denying it, but what do you base that ID upon? I would love to see that source. Thanks for replying.

[gturner333]

Here are more pics of the ends.

[Anomotodon]

1 minute ago, gturner333 said:

Interesting. I'm not denying it, but what do you base that ID upon? I would love to see that source. Thanks for replying.

I have added a link to the original paper describing this species - https://sci-hub.tw/https://www.jstor.org/stable/pdf/4523160.pdf?casa_token=088QR-jz7lkAAAAA:gx7DYPj4Jx578ekhMmo73kVjH0baMfMfhE22tjUs3hAJOmcxdrULPi4EGScfbxsNUDMHS9Egncuch-_51DmeUUXibX6nMjssyneEEPP3GMuDEPLr_wKryg&seq=1#page_scan_tab_contents

Here is a picture from that paper

 

Another paper with a similar Amiidae species https://s3.amazonaws.com/academia.edu.documents/31360690/2013_Martinelli_et_al_Amiidae_Fm_Marilia_Uberaba.pdf?AWSAccessKeyId=AKIAIWOWYYGZ2Y53UL3A&Expires=1531708778&Signature=%2FlzTRPpNJIJ%2BQjKd2Dh%2FE%2Fb4aLk%3D&response-content-disposition=inline%3B filename%3DFirst_fossil_record_of_amiid_fishes_Hale.pdf

 

Can't find any good pictures of Champsosaurus teeth but here is a description

The long, slender recurved teeth along the margins render it a most effective device for catching fish. (Erickson, 1985)

[Anomotodon]

Here is a choristoderan (maybe Champsosaurus) tooth from Campanian of NC

And a related species from Eocene Kazakhstan with tooth pictures

https://www.researchgate.net/profile/Alexander_Averianov/publication/235807470_The_first_choristoderes_Diapsida_Choristodera_from_the_Paleogene_of_Asia/links/00b7d5177790a9f728000000.pdf

[Troodon]

I have a Champsosaurus jaw with teeth and publication and its not that will post photos.  I agree with Anomotodon is the Amiid fish M. thomasi.  Most of the vertebrae  you are seeing belong to this fish.

 

Here is a an illustration of Champsosaurus from late Cretaceous 

[Troodon]

Your theropod tooth is a Dromaeosaurid indet. like StevenJD said.  No species is described from the Aguja fm.

[Anomotodon]

Second tooth is also a bony fish, might be a gar Lepisosteus sp. Here is a modern jaw

[Troodon]

Your middle tooth is the crown of a shark tooth like ynot indicated. 

Some of candidates are shown below possibly a Hybodus 

[Anomotodon]

11 minutes ago, Troodon said:

Your middle tooth is the crown of a shark tooth like ynot indicated. 

Some of candidates are shown below

 

Also thought about a hybodont crown, but it just doesn't feel right about the shape of the tooth, especially the root part. Thick enamel is a problem though, but Lepisosteus also has this feature.

[Troodon]

16 minutes ago, Anomotodon said:

Also thought about a hybodont crown, but it just doesn't feel right about the shape of the tooth, especially the root part. Thick enamel is a problem though, but Lepisosteus also has this feature.

Agree , Just a shot in the dark.  

Some more shark teeth from Aguja

[gturner333]

From the pictures, Melvius thomasi looks like a good match.

 

Troodon, you mentioned above that most  the vertebrae I see would be from this fish. Are you talking in general about most of the vertebrae that are found in the Aguja are from this fish? Also, I have found what I believe to be fish teeth and scales. One site showed similar pictures of teeth and scales from Lepisosteus alligator gar from Hell Creek formation. Could the attached pics from the Aguja be that gar or perhaps the H. thomasi? Do you have a link to the text with IDs for the above picture of shark teeth in the Aguja?

 

I appreciate the links some of you have included. They are helping me to ID some of the sawfish, ray, and shark teeth that I am seeing.

[Troodon]

Im going through the same matrix you are and most vertebrae are fish with the occasional shark.  I believe the teeth and scales you show above are Lepisosteus sp.

 

Aguja Assembladge.pdf

 

[Troodon]

Here is another

https://www.google.com/url?sa=t&source=web&rct=j&url=https://ttu-ir.tdl.org/ttu-ir/bitstream/handle/2346/48850/SCHUBERT-THESIS.pdf%3Fsequence%3D2&ved=2ahUKEwiNv-jsi6TcAhUCFogKHVD7AGYQFjABegQIABAB&usg=AOvVaw1IJn4-xqu-sDGH2U9C3jO_

[gturner333]

Those are really helpful, Troodon. Thanks. 

[Troodon]

Just did some checking on Melvis and its not described from the Aguja Fm although it may be present.  Probably best described as cf Melvis or Amiid indet.