Ammonites? They're Roundish Anyway.

[GKH]

Hello. I signed up this evening after I looked over the board. As knowledgeable as the members here are I was hopeful you could help me. I know nothing about fossils, except they're mostly really old. Anyway, the ones in the pictures are from the Middle East (at least that's what my friend said). I tried to get the picture as clear as I could. I hope it's up to par. And thank you for your help!

Greg.

[Ludwigia]

Based on the form of the sutures, they look to me like goniatites (order Goniatitida), which were the precursors of the true ammonites (order Ammonitida). A lot of material like that comes out of Morocco. Both are cephalopods belonging to the subclass Ammonoidea. Ceratites (order Ceratida), which preceded the Ammonitida chronologically, also belong to that subclass. There are several other orders as well, but the three mentioned are the main ones. There is a layman's tendency to call anything with a flat spiral form an ammonite, which is essentially okay for day to day usage, since the name of the subclass invites one to do that. Scientifically they are all referred to as ammonoids but one should differentiate between the types. This link gives good basic information.

http://en.wikipedia.org/wiki/Ammonoidea

Edited May 10, 2015 by Ludwigia

[GKH]

Thank you for the info, Ludwigia. It's cool to know these predate the ammonites. I'll pass this along and let my friend know he has something older than he thought.