Page 71 - The Freshwater Mussels of Oklahoma

Partial Synonymy:
Actinonaias rafinesqueana (Frierson, 1927), Johnson 1980
Lampsilis rafinesqueana Frierson, 1927, Branson 1984; Oesch 1984; Turgeon and
others 1988
Description:
“Shell oblong, dorsal line gently rounded, ventral line straight to gently curved;
anterior end uniformly rounded, posterior end truncated above and at the posterior ridge
which usually gives it a biangulate appearance. Shell is strong although relatively thin;
size to 9.5cm; compressed; posterior ridge broadly rounded dorsally becoming flattened
and biangulate ventrally. Beaks low, only slightly raised above the hinge line;
inequipartite; beak sculpture consists of a number of fine lines rounded up posteriorly;
growth-rest lines prominent; the epidermis is usually darker colored in the grooves.
Epidermis light brown and has a dull, waxy luster; it usually becomes dark brown with
age; green rays usually cover the surface, rays are often discontinuous, especially during
the second and third year of growth; during this period the shell usually exhibits chevron-
and Y-shaped patterns.
Left valve has two stout, divergent, striated, triangular pseudocardinal teeth; the
two lateral teeth are short, stout and slightly curved. Right valve has a tall, triangular to
columnar, striated pseudocardinal; a low, lamellar tooth can be seen anteriorly; right
lateral tooth is short, stout and slightly curved. Interdentum present but not broad; beak
cavities relatively shallow; nacre bluish-white to white, slightly iridescent posteriorly”
(Oesch 1984, p219-220).
Hosts for Glochidia:
Unknown
Comments:
Very similar in appearance to Actinonaias ligamentina and often confused with
that species.

Table 10. Summary of L. rafinesqueana shell characters.

Mean H/L Max. Mean W/L
H/L Range Length W/L Range
Location Sex N (%) (%) (mm) (%) (%) Remarks
Arkansas River Drainage
Caney River ♂ 2 62.3 61.9-62.6 115 - - subfossil
♀ 1 - 68.4 114 - - subfossil
Verdigris River ♂ 2 64.4 63.0-65.8 119 - 41.2 subfossil
Neosho River ♂ 3 61.5 58.3-65.7 120 - 42.4 subfossil
♀ 2 62.1 61.6-62.5 136 - - subfossil
Illinois River ♂ 23 61.7 56.3-66.4 135 38.5 31.3-45.7 1 with pinkish
teeth
♀ 26 65.1 59.2-69.5 150 41.6 35.4-46.1

General Distribution:
Southwestern Missouri, southeastern Kansas, northwestern Arkansas and
northeastern Oklahoma.

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