Pfeiffer, J.M., A.E. Sharpe, N.A. Johnson, K.F. Emery & L.M. Page. 2018. Molecular phylogeny of the Nearctic and Mesoamerican freshwater mussel genus Megalonaias. Hydrobiologia 811: 139-151. Available electronically.
+ Unio crassus var. giganteus Barnes, 1823
+ Unio heros Say, 1829
+ Unio multiplicatus Lea, 1831
+ Unio nicklinianus Lea, 1834
+ Unio boykinianus Lea, 1840
+ Unio digitatus Morelet, 1851
+ Unio eightsii Lea, 1860
+ Unio triumphans B.H. Wright, 1898
+ Unio (Crenodonta) stolli Martens, 1900