Triassic reptile or fish tooth?

[cck]

Going through some rocks collected in one of the triassic basins of the Newark supergroup in Virginia, and this popped out. Length is 5/8 inch, width is 1/8 inch. It looks toothy to me… any ideas?

[jpc]

I think even the Triassic folks here will need sharper photos...

Nice find, though.

 

[Fossildude19]

Pictures aren't great, but it looks fishy to me. I don't know what type of Triassic fish would have a tooth of that size, however. 

 

Any chance of more prep work on this to expose more?

And what is the item to the far left in the second picture? Fish scale?

 

Cropped and contrasted:

 

 

[cck]

Hey thanks I know the pics aren’t great.. I’ll try to get some better ones posted. Item on the lower left I think is a partial fish scale. This would be a shallow water environment… 

[cck]

And I’m a little scared of destroying it with prep.. matrix is fragile

[Fossildude19]

Just now, cck said:

Hey thanks I know the pics aren’t great.. I’ll try to get some better ones posted. Item on the lower left I think is a partial fish scale. This would be a shallow water environment… 

 

Is the tip lighter in color, as it appears to be in the photos?

That would imply an acrodin cap covering, so definitely fish.

 

[cck]

That’s a trick of the light and matrix I think. Apologies for the bad photos.. working on better

[cck]

This ‘tooth ‘ is going to the VA museum of natural history. I’ll keep posting if new info arises.

[cck]

For scale

[cck]

And a more detailed picture

[RuMert]

Unfortunately still very vague idea of how the tooth looks judging by these pictures

[cck]

Can anyone enumerate what details are important to focus on? What about the possibility that it’s a spine rather than a tooth? 

[Fossildude19]

General outline, textures present or not, enamel, tip color.

I think this is likely a fish tooth from a larger fish, but hard to confirm with the pictures currently.

Too small to be a spine, I think.

 

[pachy-pleuro-whatnot-odon]

It's always rather tricky to identify fossils from the Triassic, especially since so much about this time period remains unknown to us. Moreover, with Triassic exposures being far and few between, there aren't altogether too many people with solid knowledge of this kind of material around. @Pemphix is one that I know of on this forum, as is @sander. @Indagator may also face some useful insights.

 

What I can tell you from my own experience is this is definitely not a nothosaurid, pachypleurosaurid or tanystropheid - all of which have markedly ribbed teeth - nor placodontid or thecodont (which would be terrestrial anyway). Upper Triassic ichthyosaur teeth already pretty much look like their Jurassic counterparts and can therefore also safely be ruled out, whereas the Upper Triassic plesiosaur teeth I know of also sport pronounced ribbing - not like the very fine ribbing shown in the close-up image. This doesn't cover all of the marine reptile diversity from the Triassic, of course - such as the rather more diverse types of teeth exhibited by early ichthyosaurs (including tribodont dentition) - but would rule out the major suspects...

 

With the strong ridge that looks like a carina visible in the closeup photograph, I doubt this would be a spine, as these would show greater lateral compression and have a different texture. So fish would be my guess too. As Tim mentioned, if we can establish the tooth has an acrodin cap, that'd be a sure confirmation of it being fish - and, as a fish-collector he should know. But we indeed need better pictures of ornamentation/texture, tooth apex and the general outline to get a better impression...

[Indagator]

This is a very difficult one to identify with the current pictures. I have a few Triassic teeth in my collection. It is difficult to id them when they are not completely prepped but i think it could be most likely crocodile. Other possibilities are ichthyosaur or less likely plesiosaur. 

 

But to be sure it needs prepping.

[pachy-pleuro-whatnot-odon]

54 minutes ago, Indagator said:

This is a very difficult one to identify with the current pictures. I have a few Triassic teeth in my collection. It is difficult to id them when they are not completely prepped but i think it could be most likely crocodile. Other possibilities are ichthyosaur or less likely plesiosaur.

 

Funny you should mention crocodile, as I've thought of this as well, especially with reference to the one apicobasal ridge visible in the close-up that may represent a carina. However, with the discoloured tip visible in the very first photograph, slight S-curve along the length of the tooth, the slender shape of the tooth overall and the apparent anastomosing striations seen in the close-up (which to me don't look fully crocodilian), fish is probably still my preferred option.

 

Just wondering, though: when you said ichthyosaur is a possibility, do you have any reference material on Middle Triassic ichthyosaur teeth that show them having a different morphology from the Late Triassic ones - that is, absence of the plicidentine enamel folds seen on most ichthyosaur teeth? The tooth also seems rather tall and slender for ichthyosaur, in my opinion.

 

One thing I forgot to add in my previous post, though, which I think we can also rule out is temnospondyl amphibian. They too have ribbed teeth.

[Fossildude19]

Ichthyosaur and Plesiosaur are not a possibility, as far as I know.

I believe the Newark Supergroup is entirely lacustrine in nature, not marine.

 

I would not rule out an aetosaur tooth.

[Plax]

Have seen a lot of phytosaur teeth from our east coast Triassic but this doesn't quite look like one.

[cck]

Thanks to all for the insights, and for tolerating my less than adequate photos. This tooth is off to professionals for proper prep and study. I’ll post if any info arises. Thanks again!

[Pemphix]

Due to the poor quality of the photos available, there is unfortunately no possibility of making reliable statements about the identification of the piece. At the very least, sharp recordings focused on the piece would be necessary. It looks like the piece is still in the matrix for the most part, which makes a serious determination even more difficult. The multitude of fossil material from the Newark Supergroup, which extends into the Lower Jurassic, requires careful assessment with the best possible image material. Below are a few links that give an impression of the Newark Supergroup. Pls. come back to the forum with sharper, focused photos of the more exposed piece.

 

https://www.ldeo.columbia.edu/~polsen/nbcp/olsen_88.pdf

https://www.ldeo.columbia.edu/~polsen/nbcp/olsen_gr_80_vsm.pdf

https://www.nysga-online.org/wp-content/uploads/2019/06/NYSGA-2001-2-The-Age-of-Dinosaurs-in-the-Newark-Basin-with-Special-Reference-to-the-Lower-Hudson-Valley.pdf

https://www.semanticscholar.org/paper/Correlation-of-the-early-Mesozoic-Newark-Supergroup-Olsen-McCune/973ce3248bf2bc5709b5c8b06af781861d78241c

https://www.palass.org/sites/default/files/media/publications/palaeontology/volume_41/vol41_part6_pp1215-1230.pdf

[sander]

Yes I agree with what is said in several post above here, the photos are still too vague. Since it is at a museum now, it is best to wait for their identification. They know the area (I hope) and they can see it much better than we can from photos.

[Andúril Flame of the West]

Hello @cck,

I found it very interesting to read through this post and to see a fossil from the Newark of VA, definitely something one doesn’t see every day. I hope you do not mind me asking, but did anyone at the museum ever get an ID on the tooth? 

[cck]

Unfortunately, this tooth remains a mystery… as well as others that have been subsequently recovered… but I think they are still being studied. 

[va paleo]

Yes still being studied. but reptile for sure 

[patelinho7]

I was just thinking about this thread. After seeing @va paleo‘s enlightening poster, hopefully more will be uncovered about this tooth. @cck, was this a Culpeper Basin or Taylorsville Basin find?
(if you don’t mind me asking. feel free to ignore that question)