Sphaeriidae is a family of small to minute freshwater bivalvemolluscs in the orderSphaeriida. In the US, they are commonly known as pea clams or fingernail clams.[3][4]
Sphaeriidae are hermaphrodites with internal fertilization. Developing young are incubated within their mother (ovoviviparity), and newborn clams look like miniature copies of the adults.[4]