Page 35 - The Freshwater Mussels of Oklahoma

Partial Synonymy:
Anodonta suborbiculata Say, 1831, Simpson 1914; Murray and Leonard 1962;
Branson 1983; Oesch 1984; Turgeon and others 1988; Vidrine 1993; Howells and others
1996
Description:
“Shell large, irregularly short ovate, thin but strong, gaping in front and behind,
subinflated, with low beaks, which are compressed in young shells but fuller in old ones,
their sculpture a few irregular, feeble undulations, each bar usually having small, sharp
tubercles, these tubercles form two imperfectly radiating rows; dorsal line somewhat
curved, ending in front and behind in a small wing or angle; dorsal slope truncated, its
outline incurved just above the low posterior ridge; the rounded posterior point about at
the median line; base line rounded; anterior end rounded, sometimes cut away a little
below; surface smooth and shining in young shells, pale, yellow-green, beautifully and
delicately rayed, with three broad rays behind; in old shells the outer growth is
concentrically sculptured and the epidermis is smoky or ashy, often banded and nearly or
quite rayless; nacre silvery and iridescent, tinted bluish or purplish” (Simpson 1914,
p400).
Comments:
An uncommon species in the state and records are probably the result of
accidental introduction.

Table 3. Summary of A. suborbiculata shell characters.

H/L Mean Maximum W/L Mean
Range H/L Length Range W/L
Location N (%) (%) (mm) (%) (%) Remarks
Lake Texoma 5 69.2-77.8 72.1 81.0 23.8-40.7 29.0 4 of these 5
were early
juvenile shells

General Distribution:
Upper Mississippi and Great Lakes drainages and some Gulf of Mexico
drainages.
Oklahoma Distribution:
Currently known only from Lake Texoma and Robert S. Kerr Reservoir but can
be expected to be introduced into almost any lake or river backwater within the state.

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