Crinoid Id Lost

[Lithologia]

hello ,

I have lost the labell of this crinoid and I was not able to find the name .

This specimen comes from Mississipian of Montgomery county , Indiana .

The slab is 10 x 10 cm .

thanks!

[jkfoam]

Lithologia,

First let me say that I am not real familiar with crinoids and paleozoic fossils in general. However I did check my references and I suggest that the identity of your speciman is Eratocrinus elegans (Hall). You have a very beautiful speciman. "Index Fossils of North America", Shimer and Shrock, and "Invertebrate Fossils", Moore, Lalicker, and Fischer, both picture Eratocrinus elegans. Now if someone else posts another identification of your fossil I would give their identification serious consideration for the reason I stated above. Also Moore, et.al. lists several references at the end of their chapter on Crinoids that you could consult if you have access to a good geology University library.

Again, really nice crinoid fossil.

JKFoam

[Lithologia]

JKFoam ,

thank you very much for your very helpfull answer .

Lithologia

[crinus]

I do believe that it is an Abortocrinus.

[Lithologia]

Thank you Crinus ,

In first , please excuse my sometimes "rusty" English .

I have looked into the "Moore" invertebrate paleontology book (it's the only one I have about US crinoids ) ...and it should be Abrotocrinus. The basals are proeminent (not clearly visible due of conservation of this specimen, but they were proeminent ).However , I have thoughts about the lenght of the arms .At the one pictured into the "Moore" and at another one in my collection (labelled as Abrotocrinus ), the arms are very longer as the one from this topic.The general morphology of the pictured one here seams not to be completely as the pictures of Abrotocrinus I found with google ..........but I know it is always possible to be another subspecies .

Thank you,

Lithologia

[crinus]

Thank you Crinus ,

In first , please excuse my sometimes "rusty" English .

I have looked into the "Moore" invertebrate paleontology book (it's the only one I have about US crinoids ) ...and it should be Abrotocrinus. The basals are proeminent (not clearly visible due of conservation of this specimen, but they were proeminent ).However , I have thoughts about the lenght of the arms .At the one pictured into the "Moore" and at another one in my collection (labelled as Abrotocrinus ), the arms are very longer as the one from this topic.The general morphology of the pictured one here seams not to be completely as the pictures of Abrotocrinus I found with google ..........but I know it is always possible to be another subspecies .

Thank you,

Lithologia

There are two species of Abortocrins found at Crawfordsville. I am not sure which is which. I did notice the difference is arms. I believe that unicus had longer arms but I am not sure about the other species. I think the other species is coreyi. I am currently on the road and cannot check any references.

crinus

[Lithologia]

Again , thank you crinus for taking the time to help to ID this specimen .

I could find the names of the 3species of Abrotocrinus know from Edwardsville formation : A.coreyi ;A.unicus and A. occidentalis .

I will try to find more information about these.

Lithologia