Page 46 - The Freshwater Mussels of Oklahoma

Partial Synonymy:
Plagiola securis (Lea, 1829), Simpson 1914
Plagiola lineolata (Rafinesque, 1820), Murray and Leonard 1962
Ellipsaria lineolata (Rafinesque, 1820), Johnson 1980; Branson 1984; Oesch
1984; Turgeon and others 1988; Vidrine 1993
Description:
“Shell subtriangular, solid, subcompressed or scarcely inflated, with a sharply
defined up-curved posterior ridge, behind which it is truncated; region of the beaks and a
considerable area of the upper part of the shell compressed; beak sculpture consisting of a
few irregular, slightly doubly-looped ridges; beaks curved forward over a small, wide
lunule passing back under the hinge, where it is filled with epidermal matter; ligament
small, brown; surface with irregular, often rude, sometimes almost sulcate, growth lines;
epidermis rather smooth, but showing fine, wrinkled loops under a glass, tawny or
yellowish-green, generally with faint, broken rays, which are made up of dots or lunate or
arrow-head markings; they are sometimes composed of alternately lighter and darker
dashes; hinge strong, the plate often flattened; left valve with two triangular, ragged
pseudodcardinals, a faint anterior third one, and two slightly curved laterals; right valve
with three pseudocardinals, the middle one the largest, and two laterals, the lower the
smaller; beak cavities moderately deep; muscle scars impressed, the anterior ones ragged;
nacre silvery-white. The male and female shell differ widely, the former are much the
larger and are considerably compressed; the female shell is somewhat humped, is more or
less inflated, is considerably produced at the posterior base and gaps a little in front and
behind” (Simpson 1914, p 304-305).
Hosts for Glochidia:
Freshwater Drum, Green Sunfish, Sauger (Watters, 1994).

Table 5. Summary of E. lineolata shell characters.
Maximum
Mean H/L H/L Range Length Mean W/L W/L Range
Location N (%) (%) (mm) (%) (%)
Arkansas River Drainage
Verdigris River 4 74.0 71.7-75.6 99 - 37.8
Neosho River 5 75.5 71.7-78.9 134 - -
Red River Drainage
Kiamichi River 1 74.8 66.3-88.6 101 43.0 32.3-57.1
Little River 9 73.8 68.1-79.2 91 45.8 44.4-46.9

General Distribution:
Mississippi River drainage in general except gulf coastal areas.
Oklahoma Distribution:
Found in the Verdigris and Neosho River systems in the northeastern part of the
state and the Kiamichi and Little River systems in southeastern Oklahoma.

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