Wednesday, November 25, 2009

Brevispirifer gregarius Brachiopod

It has taken a while to find an intact specimen of this brachiopod. It has special significance in the Louisville area. The fossil marks a zone of the Jeffersonville Limestone. The small book entitled Middle Devonian Type Jeffersonville Limestone at the Falls of the Ohio by James E. Conkin, Barbara Conkin, and Larry Steinrock refers to this fossil quite a bit. The book and the Internet do not have good images for identification. Recently, I was lucky to find several complete ones. In the past, I have found the shells in rock plates, just one half, or fragments.



These specimens were found in Jeffersonville Limestone and existed in the Middle Devonian Period.


This brachiopod is known as the Brevispirifer gregarius and the ones in this picture range in size of 1-1.5 cm wide, 1-2 cm tall. It was named by Clapp in 1857 as Spirifera gregaria. The brachiopod is also found in Ohio in the Columbus Limestone.







Now that I have found some good specimens, I need to get a good photo of the Devonian Period horn coral Bordenia knappi.

5 comments:

Shamalama said...

Great specimens and really great pictures. I especially like the 2/3 profile where you can see how exaggerated the shell looks in the vertical.

Michael Popp said...

Yes, the curves are fantastic on this species.

It appears I found part of Brevispirifer that is shown in a August 13, 2009 post. (See http://louisvillefossils.blogspot.com/2009/08/unidentified-devonian-brachiopod.html)

Besides the two fossils shown in the pictures, I found 3 other intact brachiopods but have not determined what they are. I also gave away a couple more I found to the person I was collecting with that day.

Shamalama said...

Yeah, very nice. Are you finding these in quarries or road cuts?

Michael Popp said...

Neither, they are being found at private sites.

I am guessing we could find these brachiopods at the Devonian Period site we were at when you were here last though.

Shamalama said...

Yeah, I know there is a layer where they are very abundant at that site, I think it's a marker layer too in the Jeffersonville Limestone. Now's a good time to visit that site since the plants should be mostly dead or dormant and you've had a summer of rains to wash things down. Maybe I'll try for a extended weekend trip out to visit you in the spring before things green up.