†family Plethocardiidae Scarlato and Starobogatov 1979 (clam)
Bivalvia - Megalodontida - Plethocardiidae
Parent taxon: Mecynodontoidea according to J. G. Carter et al. 2011
See also Bouchet et al. 2010
Sister taxa: Beichuaniidae, Congeriomorphidae, Mecynodontidae, Prosocoelidae
Subtaxa: Plethocardia
Ecology: facultatively mobile infaunal suspension feeder
Distribution:
• Ordovician of Canada (1: Ontario collection), the Russian Federation (1), United States (19: Illinois, Iowa, Minnesota, Minnesota, Illinois, Iowa)
Total: 21 collections each including a single occurrence