Pennsylvanian Brachiopod Bi-Valve?

[Lucid_Bot]

Howdy! Found this little critter today in Allegheny county, Pennsylvania. It is Pennsylvanian, Glenshaw Formation, probably Brush Creek Limestone. It's a bit different from the ones I'm used to finding and I don't see anything similar in my guides. It is approximately 1.75 cm x 1.25 cm. Even if it can't be ID'd I'd appreciate it if someone could tell me if it's brachiopod or bi-valve. Thanks in advance.

[Fossildude19]

Bivalve.

[Tidgy's Dad]

Yup, not a brachiopod, sadly.

Nice fossil, though. 

[ClearLake]

I am going to suggest Acanthopecten and most likely A. carboniferous based on the shape, number of costae and the keel on them. It is known from the Brush Creek. All this info is from Hoare, et al (1979] Pennsylvanian Marine Bivalvia and Rostrochonchia of Ohio. 

[cngodles]

Pennsylvanian Marine Bivalvia and Rostroconchia of Ohio, Bulletin 67
Richard D. Hoare, Myron T. Sturgeon, Eugene A. Kindt
1979
77 pages, 18 plates

This out-of-print publication is a good resource for plates and descriptions of Pennsylvania bivalves. This publication is currently out of print but is downloadable for free from the Ohio State University Knowledge Bank: http://hdl.handle.net/1811/78537

 

This is your best bet today for identifying many bivalves from the Conemaugh Group.