Nephronaias is a poorly understood genus found in Central America and in Cuba. The general morphology of the included species — at least for those for which it it known — suggests a close affinity to Elliptio and Pleurobema, which are found further north in the United States and Canada.
Only one other freshwater mussel is known from Cuba, and that is "Nephronaias" gundlachi. Johnson (1981) considered gundlachi to belond in the genus Villosa. While it is clear that "N." gundlachi is a lampsiline, given its sexual dimorphism and brooding anatomy, we are not certain that Villosa is the best place for it.
Both of the freshwater mussel species on Cuba appear to be endemic to that island. The only other Caribbean island with mussels is Trinidad, but its species all co-occur in nearby Venezuela.
