Page 90 - The Freshwater Mussels of Oklahoma

Partial Synonymy:
Symphynota costata (Rafinesque, 1820), Simpson 1914; Isely 1925
Lasmigona costata (Rafinesque, 1820), Murray and Leonard 1962; Valentine and
Stansbery 1971; Johnson 1980; Branson 1983; Oesch 1984; Clarke 1985;
Turgeon and others 1988; Vidrine 1993; Watters 1995
Description:
“Shell long rhomboid, subcompressed, solid, inequilateral, with scarcely elevated,
compressed beaks, their sculpture consisting of a few strong, straight or slightly double-
looped ridges; posterior ridge well developed, sometimes partly double; posterior slope
covered with strong, corrugated, radial costations; hinder half of the disk often slightly
corrugated; growth lines strong and irregular; epidermis yellowish-green, tawny or
brownish, often rayed, dull or subshining; left valve with a strong ^-shaped reflexed tooth
under the beak, often with a low one in front of it; right valve with an irregular,
subtriangular tooth in front of the beak, the hinge plate cut away behind it; laterals low
and much blurred; muscle scars large, impressed, the anterior ones separate; nacre
whitish or straw-colored” (Simpson 1914, p 488-489).
Hosts for Glochidia:
Carp (Watters, 1994).

Table 14. Summary of L. costata shell characters.

Maximum
H/L Range Mean H/L Length W/L Range Mean W/L
Location N (%) (%) (mm) (%) (%)
Arkansas River Drainage
Illinois River 13 50.6-58.9 52.1 162 26.8-39.0 30.2
Red River Drainage
Little River 1 52.9 - 138 34.8 -
Glover River 5 47.8-57.5 53.4 120 26.1-35.8 31.6
Mountain Fork River 4 51.3-53.7 52.7 156 29.9-36.5 32.3

General Distribution:
Most of the Mississippi River River Drainage except the lower reaches. Also,
parts of the Great Lakes and St. Lawrence River drainage.
Oklahoma Distribution:
Found in the Little River system in southeastern Oklahoma and in the Illinois
River of northeastern Oklahoma. One record exists for the Verdigris River.

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