Spirifera vericosa brachiopod found in Jeffersonville Limestone of Clark County, Indiana. Animal existed in the Devonian period. These small but well defined brachiopods are sometimes used in jewelry.
UPDATE: I changed the identification of this brachiopod from Mucrospirifer to Spirifera.
6 comments:
Mike, Are you sure that is a Mucrospirifer and not a Spinocyrtina?
I see that KPS labels one of their brachiopods the Spinocyrtina so it is found in this area.
What about Mediospirifer?
I believe Mediospirifer has a smaller interarea and it is slightly curved with a curled "beak" seen on both valves. Your specimen has a flat interarea with no "beak" on the pedical valve. Here is a post I did a little while ago with, what I believe, is a Spinocyrtina from the Jeffersonville. http://viewsofthemahantango.blogspot.com/2010/06/common-spirifers-of-middle-devonian.html
Another thing which leads me to think it is a Spinocyrtina is the fact the Cyrtina has the same look only its smaller.
If you look at Nettleroth's Fossil Shell book he has quite a few illustrations that match this brachiopod. One match is the Spirifera vericosa. I am guessing it has a more modern name by now.
I think the Cyrtina has shorter wings than the brachiopod shown in this post.
The first brachiopod in your post looks like an Orthospirifer and in the Nettleroth book a Spirifera alwaterana.
Mike, I have to defer to you in this discussion. After further research I found this article on the Deep Blue site: http://deepblue.lib.umich.edu/handle/2027.42/48301
The plates and descriptions seem to support that Spinocyrtina is an entirely different shell that what I have labeled as such in the past. Since Cyrtina, while a smaller shell, has a similarly shaped interarea as the one you posted, I have assumed that Spinocyrtina would have a congruent feature. Now I need to go back and figure out what I read that gave me that idea. Back to the mystery box for those fossils, for now.
Your comments prompted me to change the identification on this brachiopod to Spirifera vericosa from Mucrospirifer.
I have a container of unidentified brachiopods as well. Good luck with your identifications!
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