|
| |||||
|
|
|
Terrestrial
Gastropods of the Columbia Basin, British Columbia
|
| Family THYSANOPHORIDAE
Pilsbry, 1926 Genus Microphysula Cockerell &
Pilsbry, 1926 Microphysula ingersollii (Bland, 1875): Spruce Snail
Description: Shell small (width, to 5.0 mm), depressed-heliciform, thin shelled, silky and translucent whitish; spire very low and very slightly convex; whorls convex and about 5.5 in number; whorls tightly coiled and slowly enlarging; periphery rounded; suture very deep; protoconch smoothish; teleoconch with very low, weak axial riblets and fine, close, evenly spaced spiral striae that are even finer and more closely spaced on the base and that are not evident on the early whorls of the teleoconch; aperture subovate and without denticles; lip unthickened and not expanded; umbilicus about 25% of the width of the shell. Similar Species: A coastal species, Microphysula cookei Pilsbry 1922, is very similar. The shell is smaller and has fewer, less tightly coiled whorls (Pilsbry 1940). Habitat: In British Columbia, Microphysula ingersollii has been recorded living under mossy boulders, rocks and dead wood in moist places. Beetle (1957) recorded this snail from an aspen grove in Wyoming. In Arizona, M. ingersollii is reported at altitudes of 981-3,353 m [6,500-11,000 ft] (Bequaert & Miller 1973). Vannatta (1914) reported M. ingersollii in Montana from 2,591 m [8,500 ft]. Berry (1919) also recorded the species in Montana, from altitudes of 1,082-1,829 m [3,550-6,000 ft] from under sticks, loose rocks, bark and small logs. Range: Rocky Mountain region; southeast British Columbia through Washington, Oregon, Idaho, Montana, Wyoming, Utah, Colorado, New Mexico and Arizona (Bequaert & Miller 1973). Distribution: In British Columbia, Microphysula ingersollii is limited to the mountain of the southeastern British Columbia where it is known from a few localities in the Columbia Basin region. Sherbrooke Trailhead in Yoho National Park is the most northern locality for this species (circa 51°26.4'N, 116°21.5'W). Name: Genus name meaning "little bubble". Species named after Ernest Ingersoll, U.S. Geological Survey naturalist, who discovered the species (Binney & Bland 1885). Records: E of Hwy bridge, S bank of Elk River
(49°10.76'N, 115°9.76'W) (Forysth Coll. 97-107-4236); Lockhart
Creek, Kootenay Lake (49°30.6'N, 116°47.1'W) (Forysth Coll.
97-099-1045); Cummings Creek, N of Sparwood (49°46.32'N, 114°54.95'W)
(RBCM 998-00293-007); along 2nd Avenue, 200 m SW of First Street
East, Field (51°23.75'N, 116°29.3'W) (Forysth Coll. 98-091-3073);
Field (51°24'W, 116°29'W) (Vannatta
1906; Pilsbry 1940); Sherbrooke
Trailhead, N of Wapta Lake, Yoho National Park (circa 51°26.4'N,
116°21.5'W) (Forysth Coll. 98-090-3389). |
|
|
 |
||
 |
Copyright © Royal
BC Museum |
|
