Page 178 - The Freshwater Mussels of Oklahoma

Partial Synonymy:
Strophitus edentulus (Say, 1829), Isely 1925
Strophitus rugosus (Swains, 1822), Isely 1925; Murray and Leonard 1962
Strophitus undulatus undulatus (Say, 1817), Oesch 1984; Watters 1995
Strophitus undulatus (Say, 1817), Johnson 1980; Branson 1983; Turgeon and
others 1988; Vidrine 1993; Howells and others 1996
Description:
“Shell generally subrhomboid, scarcely inflated, rather thin, inequilateral, with
high beaks, whose sculpture consists of a few very strong ridges running parallel with the
growth lines, turning up somewhat behind; behind these there are usually a few radial
lirae; posterior ridge generally well developed and angular, sometimes double; surface
with fine growth lines; epidermis dull ashy, ashy-green or smoky, often with faint, darker
rays; hinge line narrow, somewhat incurved in front of the beak, having the merest
vestiges of pseudocardinals and no laterals; beak cavities not deep; nacre bluish, often
straw-colored, buff or pale salmon in the shell cavities” (Simpson 1914, p 349).
Hosts for Glochidia:
Creek Chub, Largemouth Bass, Green Sunfish?, Plains Killifish?, it has also been
reported that the species is a facultative parasite and does not necessarily need a fish host,
(Watters, 1994).

Table 34. Summary of S. undulatus shell characters.

H/L Range Mean H/L Length W/L Range Mean W/L
Location N (%) (%) (mm) (%) (%)
Arkansas River System
Illinois River 2 56.2-56.5 56.4 108 34.8-35.2 35.0
Red River System
Kiamichi River 9 57.5-63.5 60.3 92 35.6-42.7 38.9
Little River 6 54.8-62.7 58.4 84 37.8-43.4 40.1
Glover River 7 56.7-61.0 59.1 98 38.3-43.3 40.8
Mountain Fork River 5 54.3-58.0 56.3 85 32.8-40.0 36.1

General Distribution:
Most of the Mississippi River system, Great Lakes, St. Lawrence, upper Atlantic
drainages and many Gulf of Mexico tributaries west to central Texas.
Oklahoma Distribution:
Found in the Little River and Kiamichi River systems of southeastern Oklahoma
and the Illinois River and other scattered localities in the northeastern part of the state.

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