Campanian Shark, Ray, Fish, Reptile, And Dinosaur Micros From The Kirtland Fruitland Formations Of New Mexico

[MarcoSr]

I want to thank Mike for sending me some Cretaceous matrix from the Campanian Kirtland and Fruitland Formations of New Mexico. I also want to thank Mike for helping me id some of the specimens. The matrix was clay based and broke down very easily by pouring boiling water over it, letting it sit overnight, and then washing it in a .4mm sieve using a water hose. There was a very high fossil density with very little matrix left and very little other debris. The species that I found reminded me of the Hell Creek Formation of Montana and the Lance Formation of Wyoming. I found a very large number of fish fossils including fish teeth and scales. I also found shark, ray, reptile, and dinosaur teeth. I’m posting the nicer and more unusual micros which I found. These micros were specimens ranging in size from .5mm to 10mm. If you place your cursor on a JPEG image you will see the file name which will have the specimen id as best that I can determine and the specimen size. If you can identify the specimens further please do so. Each matrix that I search makes me more of an avid micro tooth collector. If anyone has or can collect good matrix with shark, ray, and fish micros please send me a PM.

Below are some of the shark teeth which I found. Note Lissodus with roots are very uncommon.

Below are some of the ray teeth which I found.

Below are some of the fish teeth, scales and skull fragments which I found.

Continued in next reply

Marco Sr.

[MarcoSr]

Below are some of the fish teeth, scales and skull fragments which I found (continued).

Below are some of the reptile teeth which I found:

Crocodile Tooth:

Alligator Teeth:

Continued in next reply

Marco Sr.

Edited September 14, 2013 by MarcoSr

[MarcoSr]

Below are the dinosaur teeth which I found.

Below is a mammal tooth that I found (edited per comments from Jess and Jean-Pierre, fourth lower premolar of a multituberculate mammal)

Some unknown specimens that I need id help.

Marco Sr.

Edited September 14, 2013 by MarcoSr

[siteseer]

Marco Sr,.

The first dinosaur tooth looks like the lower fourth premolar of a multituberculate mammal. The last of the unknown specimens might be a premolar of another group of Late Cretaceous mammals.

Jess.

Below are the dinosaur teeth which I found.

Dinosaur tooth1 7mm.jpgDinosaur tooth2 4mm.jpgDinosaur tooth3 2mm.jpg

Some unknown specimens that I need id help.

Unknown3 3mm.jpg

Unknown4a 3mm.jpgUnknown4b 3mm.jpg

Unknown5 2mm.jpg

Marco Sr.

[MarcoSr]

Marco Sr,.

The first dinosaur tooth looks like the lower fourth premolar of a multituberculate mammal. The last of the unknown specimens might be a premolar of another group of Late Cretaceous mammals.

Jess.

Jess

Thank you for the id help. I wasn't expecting any mammal teeth in this matrix. JPC also said in a PM to me that he also thought Dinosaur tooth1 was a fourth lower premolar of a multituberculate mammal.

Marco Sr.

[sixgill pete]

Again, wonderful micro's Marco.

[siteseer]

No problem. I've seen some Hell Creek stuff. Those premolars are distinctive. I forgot to mention that you found a couple of great Lissodus teeth. As you noted, it's tough to get them with a good amount of root. A friend once picked up a collection of Hell Creek teeth. He had about 50 Lissodus teeth but only one had a complete root. One had a decent root - just a little wear.

Those fish teeth with the "arrowhead" tips resemble teeth I've seen from the Eocene of Virginia and Belgium identifed as Trichurides or Euthrichurides but it may be just a passing resemblance.

Jess

Jess

Thank you for the id help. I wasn't expecting any mammal teeth in this matrix. JPC also said in a PM to me that he also thought Dinosaur tooth1 was a fourth lower premolar of a multituberculate mammal.

Marco Sr.

[jpc]

Hi Marco-

I think your unknown3 is another rear tooth of an alligator... "button tooth" we call 'em around here.

[Ridgehiker]

Great specimens. I just sifted through a 10 liter bucket of Campanian sedoiment I brough home this week and posted a few much less quality photos to my thread on Lost River, Alberta.

Some same genera. I used to think what you called Trichurides were small sawfish teeth because they resembler the large ones we find....but now I think our little ones may also be something else.

Curious. How are you differentiating crocodile and alligator teeth?

[MarcoSr]

Great specimens. I just sifted through a 10 liter bucket of Campanian sedoiment I brough home this week and posted a few much less quality photos to my thread on Lost River, Alberta.

Some same genera. I used to think what you called Trichurides were small sawfish teeth because they resembler the large ones we find....but now I think our little ones may also be something else.

Curious. How are you differentiating crocodile and alligator teeth?

The Kirtland Fruitland Formation clay was very concentrated with fossils. All of these fossils came from a gallon of unprocessed clay. I'll check out your thread.

The alligator teeth are much smaller. The alligator teeth shown here are 1mm to 3mm, The Crocodile tooth is 10mm. But the main difference is the Crocodile tooth has a round or circular base and the alligator teeth have a very compressed base.

Marco Sr.

[MarcoSr]

Hi Marco-

I think your unknown3 is another rear tooth of an alligator... "button tooth" we call 'em around here.

Jean-Pierre

Thank you for the id help. I was thinking alligator but this tooth had many more and longer ridges so I really wasn't sure.

Marco Sr.

[MarcoSr]

No problem. I've seen some Hell Creek stuff. Those premolars are distinctive. I forgot to mention that you found a couple of great Lissodus teeth. As you noted, it's tough to get them with a good amount of root. A friend once picked up a collection of Hell Creek teeth. He had about 50 Lissodus teeth but only one had a complete root. One had a decent root - just a little wear.

Those fish teeth with the "arrowhead" tips resemble teeth I've seen from the Eocene of Virginia and Belgium identifed as Trichurides or Euthrichurides but it may be just a passing resemblance.

Jess

Jess

I have a good number of Lissodus from multiple sites including Hell Creek and like you said the vast majority are totally missing their roots. I do have a few very nice specimens with full roots from the Triassic of Belgium.

Marco Sr.

[busyeagle]

Love those Cretaceous fossils, wish we had more opportunities to collect those in this area.

[MarcoSr]

Love those Cretaceous fossils, wish we had more opportunities to collect those in this area.

I agree. That is why I really enjoy trading for and searching matrix from all over. I get to find specimens from all different sites around the US and the world that I will never be able to get to in person.

Marco Sr.

[PFOOLEY]

Marco, you are welcome. You found some wonderful specimens... things I have never seen. Your work has been a great learning experience.

Thank you for the excellent sample of your local fauna in return... spectacular!...

...I look forward to what you will be sifting next.

[jpc]

Personally, I've never distinguished between croc and alligator teeth... except for the rear button teeth are alligator.

[Ridgehiker]

Is there any comprehensive paper on western Cretaceous croc material? I have individual ones on Leidyosuchus, Albertachampsa,etc. but nothing looking at them as a group with comparative dentition. One would think that teeth would morph over a few million years and the changes would be within the range of both crocodile and alligator.

[MarcoSr]

Marco, you are welcome. You found some wonderful specimens... things I have never seen. Your work has been a great learning experience.

Thank you for the excellent sample of your local fauna in return... spectacular!...

sample.jpg

...I look forward to what you will be sifting next.

Mike

I really enjoyed the Kirtland Fruitland matrix, a lot of really nice specimens. Thank you again for sending the matrix. I'm glad you like the Virginia specimens.

Marco Sr.

Edited September 18, 2013 by MarcoSr

[MarcoSr]

Personally, I've never distinguished between croc and alligator teeth... except for the rear button teeth are alligator.

Jean-Pierre

I'm not an expert at distinguishing between crocodile and alligator teeth. Alligator teeth are blunter and better designed for crushing. The experts probably called the Brachycampsa an alligator because of the rear crushing or button teeth. The teeth of Brachycampsa that I found in this matrix are pretty distinctive with their very small size and very compressed bases. Most other alligator/crocodile teeth are too similar and I don't try to distinguish between them either.

Marco Sr.

[MarcoSr]

Is there any comprehensive paper on western Cretaceous croc material? I have individual ones on Leidyosuchus, Albertachampsa,etc. but nothing looking at them as a group with comparative dentition. One would think that teeth would morph over a few million years and the changes would be within the range of both crocodile and alligator.

Two USGS folks are working on a paper on Paleocene crocodiles/alligators. They have found a couple of new species by examining collections of amateurs like myself. I'm not sure when they will publish. They are still gathering data.

Marco Sr.

[Al Dente]

Personally, I've never distinguished between croc and alligator teeth... except for the rear button teeth are alligator.

My opinion is teeth are not diagnostic for differentiating alligator from crocodile, even rear button teeth. Modern dwarf crocodiles have button like teeth in the rear of their jaws. https://www.google.com/search?q=dwarf+crocodile&source=lnms&tbm=isch&sa=X&ei=F6A5UuKuHeSwyQGjooHABA&sqi=2&ved=0CAcQ_AUoAQ&biw=1301&bih=567&dpr=1#q=dwarf+crocodile+skull&tbm=isch

[MarcoSr]

My opinion is teeth are not diagnostic for differentiating alligator from crocodile, even rear button teeth. Modern dwarf crocodiles have button like teeth in the rear of their jaws. https://www.google.com/search?q=dwarf+crocodile&source=lnms&tbm=isch&sa=X&ei=F6A5UuKuHeSwyQGjooHABA&sqi=2&ved=0CAcQ_AUoAQ&biw=1301&bih=567&dpr=1#q=dwarf+crocodile+skull&tbm=isch

Very interesting. Just another case of where amateur collectors are trying to decipher what the experts have established with the existing papers on alligators and crocodiles. I showed my Brachychampsa specimens from Montana, Wyoming and New Mexico to a reptile expert who was examining some of the reptile teeth in my collection for a paper he was writing and he felt that the teeth were not alligator at all but lizard. Today they will be alligator. Tomorrow crocodile. Then maybe lizard or something else. Even using DNA testing on extant species where do you draw the line and call the species something different.

Marco Sr.