|
Please
Note: Red text
is defined in the Glossary
Description
Rafinesque described the slippershell mussel in 1820 from the Ohio
River. This species has a small, moderately solid, rhomboid shaped
shell that rarely exceeds 55 mm in
length. Shells are thicker towards the anterior
end. The periostracum can be
yellowish brown or light yellow, with wavy green rays;
however, the periostracum on most adult specimens in North Carolina
is dark brown. The nacre is bluish
white or creamy beige, and the posterior margin
may be slightly iridescent blue. Lateral teeth
are indistinct and may be represented by a slight swelling along
the hinge line. Each valve
has one, stumpy pseudocardinal tooth.
Sometimes, an additional, vestigial
pseudocardinal tooth may be present in each valve.
Distribution
(see map)
This species has a widespread distribution that includes the
Upper Mississippi River Basin; Ohio, Cumberland and Tennessee River
Subbasins; St. Lawrence River Basin; and Lake Huron, Lake St. Clair,
and Lake Erie drainages in Canada.
Distribution by
County: Little Tennessee River Basin: Swain Co. (Little Tennessee
River Basin); French Broad River Basin: Henderson Co. (Mills River
Subbasin). NOTE: All headwater areas that flow into these occupied
habitats should receive special management.
Habitat Preferences
This species has been found in a wide variety of habitats across
its range. In North Carolina, the slippershell mussel inhabits riffle
areas with gravel/cobble/boulder substrate. In other locations,
the species has been found in small to large streams and lakes;
substrates ranging from silt and sand to cobble; and slow to fast
currents. It is often found in and around waterwillow, Justicia
americana.
Life History
The slippershell mussel is a bradytictic
brooder, with gravid females
observed from fall through spring (Baker 1928, Clarke 1981, Zale
and Neves 1981). Hermaphroditic individuals
also have been found (Ortmann 1911). Identified fish hosts for this
species include the banded sculpin, the mottled sculpin, and the
johnny darter (Clarke 1981, Zale and Neves 1981).
|
