Identificaciones de jenaemo

Only a single pair of shells was seen on the lower end of a gravel bar. It appeared to have been recently eaten. I have never seen this species before, and I don't know mussels well at all, so I won't even guess at the species yet.

8-15-2016: added four photos of umbo, posterior end, and shell surface on posterior end after flaking calcite encrustations off part of a shell. Several folks have looked at it in-hand and seem to be undecided between R. petrina and Fusconaia mitchelli. Maybe these photos will help confuse things!

Only a single pair of shells was seen on the lower end of a gravel bar. It appeared to have been recently eaten. I have never seen this species before, and I don't know mussels well at all, so I won't even guess at the species yet.

8-15-2016: added four photos of umbo, posterior end, and shell surface on posterior end after flaking calcite encrustations off part of a shell. Several folks have looked at it in-hand and seem to be undecided between R. petrina and Fusconaia mitchelli. Maybe these photos will help confuse things!