Page 118 - The Freshwater Mussels of Oklahoma

Partial Synonymy:
Obovaria jacksoniana (Frierson,1912), Simpson 1914; Johnson 1980; Branson
1984; Oesch 1984; Turgeon and others 1988; Vidrine 1993; Howells and
others 1996
Description:
“Shell small; dorsal and ventral margins gently rounded; anterior end uniformly
rounded, posterior end sharply rounded in the male and bluntly truncated in the female.
Shell stout, the anterior half thicker than the posterior half; size to 4.3cm; moderately
inflated; posterior ridge not prominent. Beaks broad and low but raised above the hinge
line, inequipartite; beak sculpture not discernable on the individuals recovered in this
study. Epidermis light to dark brown; green capillary rays cover the posterior two-thirds
of the shell.
Left valve has two stout, erect, roughened, triangular pseudocardinal teeth; the
lateral teeth are long, roughened and slightly curved. Right valve has a single erect,
columnar, grooved, emarginated pseudocardinal tooth; a small compressed, emarginated
tooth can be seen anteriorly; lateral tooth high, roughened and slightly curved.
Interdentum narrow to absent; beak cavity shallow; nacre bluish-white, iridescent
posteriorly” (Oesch 1984, p 161).

Table 21. Summary of O. jacksoniana shell characters.

Maximum
H/L Range Mean H/L Length W/L Range Mean W/L
Location N (%) (%) (mm) (%) (%)
Red River System
Kiamichi River 31 66.7-84.6 73.4 48 42.9-63.2 54.3
Little River 18 61.1-87.5 72.5 41 44.0-70.0 50.4
Glover River 28 61.4-82.4 74.7 48 44.0-65.6 53.9
West Fork of Glover River 14 68.0-80.5 75.0 49 47.6-58.3 51.4
Mountain Fork River 31 63.9-77.4 71.1 45 43.3-54.8 48.5

General Distribution:
Southern Mississippi River drainage and adjacent Gulf of Mexico tributaries from
easern Texas to Mississippi.
Oklahoma Distribution:
Found only in the Kiamichi and Little River systems in southeastern Oklahoma.

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