Page 135 - The Freshwater Mussels of Oklahoma

Partial Synonymy:
Lampsilis purpurata (Lamarck, 1819), Simpson 1914; Isely 1925
Proptera purpurata (Lamarck, 1819), Isely 1925; Murray and Leonard 1962;
Johnson 1980; Branson 1984
Proptera capax (Green, 1832), Murray and Leonard 1962 (based on the
misidentification of a large, obese female Potamilus purpuratus)
Potamilus purpuratus (Lamarck, 1819), Valentine and Stansbery 1971; Oesch
1984; Turgeon and others 1988; Vidrine 1993; Howells and others, 1996
Description:
“Shell very large, somewhat obovate, inflated, with full, high beaks, having very
faint, corrugated sculpture, scarcely winged in front, with a low, angular wing behind;
there are two or sometimes three low, radiating ridges on the posterior slope; surface
nearly smooth or somewhat sulcate, covered with a shining, blackish epidermis; ligament
large and long, generally exposed in adult shells; left valve with two subcompressed to
solid, ragged pseudocardinals and two strong, remote laterals, the hinge line rounded
between the two sets of teeth; right valve with two pseudocardinals, the lower the larger,
and one strong, truncated lateral; beak cavities rather deep, with a row of deep scars
running towards the anterior base; muscle scars large, the anterior deep and smooth, the
posterior scarcely impressed; nacre rich, dark purple, somewhat iridescent behind, much
thicker in front. Male shell full at the posterior base, rounded and obtusely biangulate
behind above the median line; the female shell has a wide, rounded, marsupial swelling
far behind, and is decidedly truncate posteriorly” (Simpson 1914, p 166).
Hosts for Glochidia:
Freshwater Drum (Watters, 1994)

Table 25. Summary of P. purpuratus shell characters.

H/L Mean Maximum W/L Mean
Range H/L Length Range W/L
Location N (%) (%) (mm) (%) (%) Remarks
Arkansas River System
Verdigris River 13 61.3-77.6 67.1 163 35.9-49.6 41.4
Caney River 17 58.2-75.9 67.3 156 35.6-49.3 40.7
Neosho (Grand) River 19 65.2-75.0 69.2 161* 34.1-53.7 41.5 4 with rays
Spring River 1 63.3 - 90 36.7 -
Illinois River 10 61.4-73.1 69.0 158 40.5-53.7 46.0
Poteau River 14 61.0-72.9 66.7 146 36.0-54.8 42.9
Red River System
East Cache Creek 3 69.0-74.1 70.9 100** 40.0-45.0 43.2
Lake Ellsworth 3 68.0-70.4 68.9 155 41.4-53.7 47.8
Lake Texoma 9 61.9-74.1 68.2 91 36.0-48.4 42.6 5 with rays
Blue River 18 59.5-75.0 64.1 158 37.7-53.0 42.7
Muddy Boggy River 15 61.2-73.0 68.1 152 35.0-52.6 44.2 1 with rays
Atoka Reservoir 29 59.4-72.2 67.3 143 34.3-44.8 39.6 23 with rays
Kiamichi River 34 59.1-73.7 67.4 128 36.2-50.0 44.0 1 with rays
Little River 9 65.5-75.0 69.4 90 39.3-54.4 48.2
Glover River 2 60.9-62.7 61.8 115 40.0-49.4 44.7
Mountain Fork River 7 58.2-71.2 66.6 170 41.7-52.4 47.0
* one half valve 183mm.
** one specimen from Medicine Creek 186mm.

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