Freshwater mussel

Freshwater mussel

Observation - Freshwater mussel. Description: I picked this shell up in the gravel of the tidal Thames at Richmond. I wonder if it is Sphaerium rivicola. It is 22mm across at the widest. There were many the same.

I picked this shell up in the gravel of the tidal Thames at Richmond. I wonder if it is Sphaerium rivicola. It is 22mm across at the widest. There were many the same.