Perhaps the most important brachiopod know from the Jeffersonville limestone formation in Kentucky is Brevispirifer gregarius. It is a common constituent of the formation and even has a zone within named after it due to the abundance of fossils. B. gregarius is a small Spiriferid type brachiopod that is roughly half moon shaped when viewing the dorsal surface of the brachial valve. The two valves are both convex with the pedicle valve a bit more than the brachial. The interarea of the pedicle valve is slightly recurved with a well defined "V" shaped foramen. The surface of both valves have coarse radiating ribs and a fold/sulcus feature.
Specimen #1 - Brachial valve with Beekite rings
These next two pictures are of a partial, dis-articulated pedicle valve interior.
Another dis-articulated pedicle valve interior. The difference in features could be a result of incomplete preservation and replacement by the Quartz. Both were collected from the same horizon in the same roadcut.
I collected these specimens from the Jeffersonville formation (Devonian, Eifelian stage) near Louisville, KY
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