Highnut

The highnut (Pleurobema altum) was a species of freshwater mussel, an aquatic bivalve mollusk in the family Unionidae, the river mussels.

Highnut
Conservation status
Extinct  (IUCN 2.3)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Bivalvia
Order:	Unionida
Family:	Unionidae
Genus:	Pleurobema
Species:	†P. altum
Binomial name
†Pleurobema altum (Conrad, 1854)

This species was endemic to rivers of the United States.

Unionids are vulnerable to habitat change and are a highly endangered taxa (70% of them are considered imperiled).^[2]