Eocarcharia? Kryptops?

[Dino Dad 81]

Hello and Happy Friday!

 

A while back I posted an alleged Eocarcharia tooth that was ultimately thought to probably be Eocarcharia, but possibly be Kryptops. I just got a more definitive Kryptops tooth that has me second guessing the Eocarcharia. So, the focus of this post is tooth #1, the smaller tooth (unless you don't think tooth #2 is Kryptops--then please let me know). Both are from Elrhaz.

 

Tooth 1 (alleged Eocarcharia and the focus of the post):

• CH: 29mm
• CL: 12mm
• CW: 5.4mm
• Mesial serration density: 4/mm

• Distal serration density: 3.4/mm

 

 

 

Tooth 2 (Kryptops comparator):

• CH: 36mm
• CL: 15mm
• CW: 6.5mm
• Mesial serration density: 3.4/mm

• Distal serration density: 3.4/mm

 

 

 

 

Comparisons, Tooth 1 on the left:

 

 

 

 

 

 

 

 

Thanks!

[Troodon]

I don't see any kryptop in these photos,  as described in the hopotype

[FB003]

Whatever they are, they sure look alike thats for sure.

[Dino Dad 81]

@Troodon are you basing that on the serrations? I included the pics of serration density just to give a decently look at the serrations. They're so worn, it's very hard to say anything about shape, but I think I'm seeing some interserrational sulci. I could try to get better pics of the serrations and crowns margins, if that'd help.

 

 

But the shape, at least on the bigger one, is clear-cut Abelisaurid, no? (Even if not Krpytops.) Do you think the two are from the same species?

 

Thank you!!

Edited October 14, 2022 by Dino Dad 81

[Troodon]

Here is another case, like most from Niger,  where we have very limited published information, just a vouple of teeth, that is all I can go on.  Unfortunately we do not have a lot of morphology information to completely identify the tooth.

  And yes the serrations on your teeth are not apically hooked and I think they should be more compressed like rugops but thats a guess. 

 

 The two teeth are from the same species.

 

 

[Dino Dad 81]

Can't thank you enough @Troodon.

 

What's your personal opinion on what FAMILY these most likely came from?

[Troodon]

I dont know, these could be Carcharodontosaurids but they seem too narrow to fit the normal morph.  The 1 (only 1) Eocarcharia tooth that was in Hendrickx study fits the more typical width.   Maybe a Noasaurid ?  That would be a better fit. 

Hey Sereno is currently in Niger on a 3 month expedition. They are spending 22 days in Gadoufaoua.  Maybe will will see some clarity to all the questions.  Unfortunately all he appears to be interested in big newsworthy finds. 

 

 

Look I found an Eocarcharia tooth no its a Kryptops no its a ....

 

[Dino Dad 81]

@Troodon, this has gotten me interested in the serrations of Rugops...just out of curiousity/learning. Is there a place to see good pictures? That holotype paper really sucks.

 

Thanks,

[Troodon]

1 hour ago, Dino Dad 81 said:

@Troodon, this has gotten me interested in the serrations of Rugops...just out of curiousity/learning. Is there a place to see good pictures? That holotype paper really sucks.

 

Thanks,

 

Sereno's papers tend to be short but you can see not much was found with the holotype, again material from Niger is pretty scarce in published form.

 

I've written a number of times of specimen UCPC 10 from the Kem Kem Group.   Most believe this is similar to Rugops.   The very short paper mainly discusses the maxilla and says this about the teeth " Denticles, spaced at 2.3–3.0 per millimeter, adorn the entire anterior and posterior carinae of each tooth, fading only at the very tip."   No close up images

 

 

RECORD OF ABELISAURIDAE (DINOSAURIA: THEROPODA) FROM THE CENOMANIAN OF MOROCCO LUKE MAHLER*, Department of Anatomy and Organismal Biology, University of Chicago, 1027 East 57th Street, Chicago, Illinois 60637 U.S.A.

[Dino Dad 81]

On 10/14/2022 at 5:42 PM, Troodon said:

I dont know, these could be Carcharodontosaurids but they seem too narrow to fit the normal morph.  The 1 (only 1) Eocarcharia tooth that was in Hendrickx study fits the more typical width.   Maybe a Noasaurid ?  That would be a better fit. 

 

@Troodon

Have any toothed Noasaurids been found in the Elrhaz formation? In Niger? 

[Dino Dad 81]

Maybe these help with a most-likely family?

 

Tooth #1

Tooth #1

 

 

Tooth #2

Tooth #2

 

Thank you!

[Troodon]

7 hours ago, Dino Dad 81 said:

Have any toothed Noasaurids been found in the Elrhaz formation? I

Nothing published

6 hours ago, Dino Dad 81 said:

Maybe these help with a most-likely family?

No change from prior remarks.  We really need to see what critters exist in that fauna.

[Dino Dad 81]

On 10/14/2022 at 5:42 PM, Troodon said:

I dont know, these could be Carcharodontosaurids but they seem too narrow to fit the normal morph.  The 1 (only 1) Eocarcharia tooth that was in Hendrickx study fits the more typical width.   Maybe a Noasaurid?  That would be a better fit. 

 

Hi @Troodon

I was researching a Noasaurid tooth and I came across these quotes in Hendrickx and thought back to the teeth in this post. Hendrickx seems to be describing Noasaurid denticles to be awfully very different than the teeth I posted here months back.

 

"Regardless of the tooth dimension, theropods with particularly small denticles, i.e., more than 6 denticles per millimeter on the distal carina, include non-neotheropod saurischians such as Aorun, Baryonychinae, Coelophysis, Compsognathidae, Eodromaeus, Eoraptor, Falcarius, Liliensternus, Noasauridae..."

 

"...teeth bearing distal denticles significantly bigger than the mesial ones [DSDI>1.2] are considered as synapomorphic for the clades Coelurosauria, Noasaurinae, and Piatnitzkysauridae."

 

I also used the same serration density pics I included in this post and see that my counts were poor.

I'm now seeing the smaller tooth (tooth 1) at:

Mesial: 19/5mm

Distal: 17/5mm

 

And the larger tooth (tooth 2) at:

Mesial: 15/5mm

Distal: 17/5mm

 

I'd be grateful to get your thoughts on whether this info makes Noasaurid unlikely for these teeth.

[Troodon]

Anything is possible but again we need to see what in that faunas and to-date we have very little information that is published.   I dont just want to look at one characteristic and say yes.  In the KK we probably only have one Deltadromeus, and thats debated.   Its teeth most likely dont look like these given the indeterminate morphs which exists.