Fort Crittendon Vert

[Masp]

This is a partial vert from the Fort Crittendon Formation, Old Santa Rita Mountains, Arizona. Anything diagnostic enough to tell what species or family this belongs to?

[frankh8147]

I'm not familiar with the formation but are there any Mosasaur remains found there?

 

One side is convex and the other is concave which makes me think Mosasaur (I'm just not sure if there are any dinosaurs with similar features).

[Masp]

56 minutes ago, frankh8147 said:

I'm not familiar with the formation but are there any Mosasaur remains found there?

 

One side is convex and the other is concave which makes me think Mosasaur (I'm just not sure if there are any dinosaurs with similar features).

There aren’t any mosasaurs described as far as I’m concerned, but everything about that area seems pretty vague to me...could it be croc possibly too?

[frankh8147]

16 minutes ago, Masp said:

There aren’t any mosasaurs described as far as I’m concerned, but everything about that area seems pretty vague to me...could it be croc possibly too?

 

The crocodile vertebrae I have seen tend to have a divot on one side which I'm not seeing here. 

 

I'm still thinking Mosasaur,  it looks right. I'm just not too familiar with the species in that area so that's what is stopping me from being definitive on this one.

 

 

 

 

[Masp]

Regarding dinosaurs I think 90% are indeterminate sp. from what I’m seeing, in any case I’m gonna compare with some mosasaur verts now  thank you

[JohnJ]

The bone texture doesn't seem like mosasaur, to me.  Is it as porous as it appears?

[Masp]

 Given that It’s only half of the vert could be misleading too maybe?

[-AnThOnY-]

Looks mosasaur to me as well, but I have zero idea about the formation or area.

 

 

[PFOOLEY]

DISTRIBUTION, AGE AND CORRELATION OF CRETACEOUS FOSSIL VERTEBRATES FROM ARIZONA

[frankh8147]

For comparison-sake, here is one I found in New Jersey that seems similar.

 

Again, I'm not saying this is 'definitely Mosasaur', just that I see some good similarities.

[Masp]

 

12 minutes ago, JohnJ said:

The bone texture doesn't seem like mosasaur, to me.  Is it as porous as it appears?

I don’t have it in my possession yet. When I receive it, I’ll post better pics so it’s easier to tell

[Masp]

2 minutes ago, frankh8147 said:

For comparison-sake, here is one I found in New Jersey that seems similar.

 

Again, I'm not saying this is 'definitely Mosasaur', just that I see some good similarities.

That’s a neat fossil...doesn’t my vert seem more flat/inward in the front in your opinion? 

[JohnJ]

The first photo in the topic seems to give the illusion of a more rounded "top".  The tilted second image shows more of what is probably a flatter surface.  The first and third photos show a separation crack (epiphysis?) on the concave end.  That, and the porous texture of the bone suggests something other than the more solid calcite infilling usually seen in fossil reptiles.

[FossilDAWG]

The Fort Crittenden Formation was deposited in a freshwater lacustrine environment.  A variety of dinosaurs , freshwater turtles, crocodiles, and fish have been found.  The most common fossils are freshwater unioid clams and snails.  No marine species are recorded from the formation.

 

Don

[Masp]

23 minutes ago, FossilDAWG said:

The Fort Crittenden Formation was deposited in a freshwater lacustrine environment.  A variety of dinosaurs , freshwater turtles, crocodiles, and fish have been found.  The most common fossils are freshwater unioid clams and snails.  No marine species are recorded from the formation.

 

Don

Does anything indicate dinosaur about this vert in your opinion?

[Masp]

31 minutes ago, JohnJ said:

The first photo in the topic seems to give the illusion of a more rounded "top".  The tilted second image shows more of what is probably a flatter surface.  The first and third photos show a separation crack (epiphysis?) on the concave end.  That, and the porous texture of the bone suggests something other than the more solid calcite infilling usually seen in fossil reptiles.

 Right, I think my best bet is to post some better pics when I receive it. 

[jpc]

Looks awfully mosasauroid to me too.  I can't think of any Cretaceous dino that has verts like this.  

 

Corrections based on the paper posted above... there are titanosaurs known from this FM and they seem to have concave/convex ends.  I don't know enough about Titanosaurs to say anything more. 

[FossilDAWG]

50 minutes ago, Masp said:

Does anything indicate dinosaur about this vert in your opinion?

I'm not very familiar with dinosaurs vertebrae so I'll defer to others on that.  My experience with the Fort Crittenden Formation includes finding turtles and a vertebra of Melvinus, an amiid fish, as well as many clams and snails.  Because of that experience I am fairly familiar with the published literature 

 

I gather that your vertebra is purchased?  In that case are you fully confident that it comes from the Fort Crittenden Formation?

 

Don

[Masp]

3 minutes ago, FossilDAWG said:

I'm not very familiar with dinosaurs vertebrae so I'll defer to others on that.  My experience with the Fort Crittenden Formation includes finding turtles and a vertebra of Melvinus, an amiid fish, as well as many clams and snails.  Because of that experience I am fairly familiar with the published literature 

 

I gather that your vertebra is purchased?  In that case are you fully confident that it comes from the Fort Crittenden Formation?

 

Don

I purchased first for the fact that it was very affordable and from a rarer locality, otherwise I would post here first - regarding if I’m confident that it’s from Fort Crittenden, I don’t know. I’m just taking the seller’s word for it. He has sold some other material from this locality before I believe. 

[Masp]

In fact, this is another listing, same seller, for a dinosaur fossil from the same locality. However this to  me looks Mosasaur. 

[JohnBrewer]

@JarrodB has more mossy verts than I’ve seen in a collection maybe he could help?

[-AnThOnY-]

2 hours ago, Masp said:

In fact, this is another listing, same seller, for a dinosaur fossil from the same locality. However this to  me looks Mosasaur. 

 

This looks mosasaur as well, even more so, haha. Hmm....

[frankh8147]

6 hours ago, Masp said:

That’s a neat fossil...doesn’t my vert seem more flat/inward in the front in your opinion? 

Thanks! 

 

There is a good amount of variation between the specimens I've seen. Mosasaur verts can vary greatly depending the species, the size of the animal, the position of the vert., the amount of wear, the preservation, etc.

 

I still have a hunch it's Mosasaur but I know nothing about Titanosaurs, and without a definitive location for these pieces, it's a tough ID!

 

Also, are both of those fossils supposedly from the same layer/preservation, or just the same location?

[Masp]

55 minutes ago, frankh8147 said:

Thanks! 

 

There is a good amount of variation between the specimens I've seen. Mosasaur verts can vary greatly depending the species, the size of the animal, the position of the vert., the amount of wear, the preservation, etc.

 

I still have a hunch it's Mosasaur but I know nothing about Titanosaurs, and without a definitive location for these pieces, it's a tough ID!

 

Also, are both of those fossils supposedly from the same layer/preservation, or just the same location?

Agreed it is tough! I’m don’t see why he would lie about this locality, even though it could always be the case.  However I think I’m going to message him and see if he can give me a background story, which would help me tremendously.  When I actually receive it I will post more pics, better quality. 

[Carl]

22 hours ago, JohnJ said:

The first photo in the topic seems to give the illusion of a more rounded "top".  The tilted second image shows more of what is probably a flatter surface.  The first and third photos show a separation crack (epiphysis?) on the concave end.  That, and the porous texture of the bone suggests something other than the more solid calcite infilling usually seen in fossil reptiles.

I agree that it doesn't exactly look like a mosasaur. I've never seen the separated epiphysis in mosasaurs like that. Not even sure I've seen it like that in dinosaurs or other reptiles. I'm entertaining the idea that it may be mammal.