Wednesday, September 7, 2011

Evactinopora

I present to you one of the strangest fossil Bryozoan species I've ever seen: Evactinopora radiata. It is known primarily from the Fern Glen limestone, where this specimen is from, but can be found in other formations that are from the very earliest Mississippian (Tournaisian). From the base (bottom) or top it looks like a starfish. Studies have shown that there are pores in the sides of the rays and that is where the individual Byrozoan polyps lived. Unfortunately none are exposed on this specimen.






 There are many questions brought up when studying the specimen: Why did it grow this way, why is it (seemingly) limited to the North American continent and why didn't it radiate into new species?



Here is a nice page that discusses Evactinopora in depth.


Thanks to Joe K. for the specimen.

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