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Hickorynut, Obovaria olivaria
Description: The Hickorynut is a
medium-sized mussel (up to 100-
110mm) that has a really thick, heavy
shell. It has a rounded shell that
looks lopsided as the posterior end is
much longer than the anterior end.
The shell is smooth and a yellowish
brown color. The nacre is white. The
beaks are prominent and curl around
to meet each other to the point that
they rub. The beak sculpture is not
very evident but is supposed to be fine
double-looped ridges.
Similar species: There really aren't
any other species in Nebraska that
look like this except for the Higgins
Eye. The Higgins Eye is supposed to
have green rays that the Hickorynut
lacks. The female Higgins Eye has a
greatly inflated shell. Since the
Higgins Eye is endangered, finding
any shell that looks like this is cause
for notifying someone of the find.
Please note that there are many other
species of mussel, not found in
Nebraska, that look like this.
Conservation status: G4, N4, SX.
This species was always rare and is
extirpated from the state.
Hosts: Lake sturgeon, shovelnose
sturgeon.
Habitats used: Large rivers in sand
or mixed sand and gravel (Cummings
and Mayer 1992). Medium to large
rivers in soft or coarse substrate and
flowing water (Seitman 2003). Small
to large gravel or mud-gravel in rivers
(Oesch 1995). Found on sand or
gravel substrates in deep water with
good current (Parmalee and Bogan
1998). Muddy sand or gravel in rivers
and lakes (Watters et.al. 2009).
Distribution: The Mississippi River
basin from western Pennsylvania and
New York to Kansas, north to
Minnesota, and south to Louisiana.
St. Lawrence from Lake Ontario to
Quebec.
Collection notes: This species has
been found twice as relict shell, once
in the Big Blue River and once in
Logan Creek. It was identified from
one archeological site in Sarpy
County.
Comments: This really could hardly
be claimed to be a Nebraska species as
it was always very rare.
