Bottlecap-shaped Paleozoic Fossil

[Helicoprion]

Can someone please identify this fossil for me? I found it in Broome County, New York and I believe it to date from the Paleozoic era as I found it in association with bivalve fossils which means the fossil in question is likely a marine species and New York was underwater during the Paleozoic. 

[Mahnmut]

Hello Helicoprion and welcome to the Forum!

I think what you got there is a crinoid stem section. imagine a stack of coins forming the stem of a sea lily.

Where I grew up they where known as "st. Bonifaz' pennies".

Best regards,

J

[Rockwood]

I think you need to go one step more. Calling it a segment implies that more than one ossicle has been preserved in articulation. These appear to be singles.

And yes, the sea level was higher relative to the land surface at the time.

Edited May 7, 2022 by Rockwood

[Mahnmut]

Thanks  Rockwood.

Well, call it the shortest possible segment/section if you will.

I surely sometimes get the details wrong, English being not my first language.

I did not hear the term ossicle applied to invertebrates before, in German the technical term is "Trochit", from Greek trochos= wheel.

Or "Seelilienstielglied" (a rather beautiful example of a German compositum).  Seelilie stands for itself in this context I think, "Stiel" meaning stalk and "Glied" meaning part, member (both meanings), segment.

Segment on the other hand comes from Latin segmentum, "cut off part", (secare = to cut.)

Sorry, you put me in a mood to be a smart asinine perissodactyl (even more than usually).

 

And indeed I did not see that there are at least three ossicles of different sizes in the specimen, thats neat!

 

Cheers,

J

 

[Ludwigia]

I agree with my predecessors. By the way, I've seen paleontologists referring to these things as stem segments, so you're probably both correct, athough Rockwood is the scientist and Mahnmut the layman as far as the jargon is concerned

[Fossildude19]

And I would go ahead and call them crinoid columnal imprints.  

Welcome to the Forum. 

NY has lots of fossil potential.

[minnbuckeye]

2 hours ago, Mahnmut said:

English being not my first language

@Mahnmut, the eloquent way you described your mood shows me y'alls command of the English language is better than mine and English is my first language!!!!

[Mahnmut]

Here is a forum link that gives a lot of information about your finds anatomical context, aswell as another example of goodwilled terminology discussion:

http://www.thefossilforum.com/index.php?/topic/65447-are-these-crinoid-columns/

Cheers,

J

 

[Tidgy's Dad]

Columnal refers to segments of the stem. 

Ossicle can be segments of the stem, holdfast rootlets, cirrii, arms etc. 

 

[abyssunder]

I call them columnal articular facet imprints. 

[Rockwood]

By the way the reason I chose to treat sections different from the individual elements is that the ligaments which hold the stem together attach to varying numbers of them leaving some in place long enough that the unit preserves after the overall form is lost.