Scaleshell (Leptodea leptodon)
(Federally listed as Endangered)
Description:
The Scaleshell is an elongate, roughly oval-shaped freshwater
mussel that grows to a length of approximately four inches. The
shell is relatively thin, and yellowish-tan in color. Overall,
this mussel has a relatively compressed and streamlined shape
that may be an adaption to living in swift flowing waters. Like
all freshwater mussels, it is a filter-feeder that filters fine
organic material, suspended algae and microscopic organisms out
of the flowing water around it.
Habitat: The Scaleshell is typically found in riffles within
relatively swift moving water. It commonly lies buried a few
inches below the bottom of the riffle in gravel or cobble
substrate.
Current and Historic Distribution: In Oklahoma, populations of
the Scaleshell are thought to remain only in the Kiamichi and
Little rivers in the Ouachita Mountains in the southeastern part
of the state. Historically, populations of the Scaleshell were
known to exist in 13 states within the Mississippi River
watershed, but currently they are known to occur only in
Missouri, Arkansas and Oklahoma.
Reasons for Decline: The causes for their decline are uncertain
but may be related to modification of river flow patterns by
reservoir construction; in-stream gravel mining, past water
pollution by pesticides, fertilizer and fine sediment; or
reductions in the populations of their fish host species.
County by County List of Endangered and Threatened Species
US Fish and Wildlife Endangered Species Lists