Among the most common pelecypods that can be found in the Moscow formations is Modiomorpha mytilodies. It's an oval shaped shell with the anterior smaller than the posterior. The surface of the shell is covered with broad, undulating concentric growth lines.
Specimen #1 is a loose cast of the shell that is compressed to nearly flat
Specimen #2 - isolated right valve
Specimen #3 - isolated left valve
Specimen #4 - Another loose cast but it's slightly deformed such that the right valve is partially folded over along the dorsal margin
These specimens were found at a borrow pit on Deep Springs Road in Madison County, NY which exposes the Windom shale member of
the Moscow formation (middle Devonian in age, Givetian stage.)