Elktoe

The elktoe (Alasmidonta marginata) is a species of freshwater mussel, an aquatic bivalve mollusk in the family Unionidae, the river mussels. This species is found in southeastern Canada and the eastern United States. Like many mussels, it is threatened by water pollution from agriculture, industry, and other development, such as acid mine drainage and sedimentation. It may be extinct in Oklahoma.

== Description == The elktoe is a moderately sized mussel of about 4 inches. The shell is thin and triangular-shaped with an inflated center. The anterior end is elongated and round and the border of the shell is marked with fine ridges. The hinge of the two shells, or umbo, is large and located near the center of the shell. The shell is a dull yellowish-green with multiple rays and dark green spots. The interior of the shell is a glossy bluish-white and may have some salmon near the edges and beak. The beak consists of double-looped ridges lined with thin teeth. The elktoe most closely resembles the snuffbox and deertoe, however, both lack a beak and teeth.