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Terrestrial
Gastropods of the Columbia Basin, British Columbia
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VERTIGINIDAE Stimpson, 1851 The complex dentition of the aperture and unique features of the outer lip of some vertiginids are described using special terminology, which is adapted from Pilsbry (1948):
The four major denticles present in all our Vertigo, except some forms of V. modesta, are the columellar lamella (Lc), parietal lamella (Lp), upper palatal plica (Pu) and lower palatal plica (Pl). Additional denticles are often present. These are the angular lamella (La), infraparietal lamella (Li), suprapalatal plica (Ps), infrapalatal plica (Pi) and subcolumellar lamella (Ls). The relative positions of these denticles are illustrated below. Designation of the type and placement of denticles by a two-letter code is an innovation of this report and is used here for brevity. Position of denticles in pupillids
Genus Columella Westerlund, 1878 Columella columella (Martens, 1830): Mellow
Column
Description: Shell small (height 2.9 mm), cylindric and brown, with a silky lustre; spire very high; apex blunt; whorls convex and numbering 6-7; often either the last whorl or the penultimate whorl is a little smaller than the adjacent whorls; periphery rounded; suture deep; teleoconch coarsely striate (much more coarse and raised than in C. edentula); aperture ovate and without denticles; outer lip thin, unexpanded and without the sinulus and crest of many Vertigo; umbilicus small. Similar Species: C. edentula is smaller, more tapering and with fewer whorls which are less coarsely sculptured. The peculiarity of coiling that reduces the size of the penultimate or last whorl in some individuals is never present in C. edentula. Habitat: This is an arctic-alpine species usually collected at high elevations (Wayne 1959, Bequaert & Miller 1973). In the Columbia Basin region, specimens have been collected on wet ground under a log near the shore of Kootenay Lake and from under dead wood and fallen leaves in a spruce forest at Field. Range: Holarctic (Forcart 1959). In North America, Aleutian Islands (Hanna 1925) and Port Clarence, Alaska (Bequaert & Miller 1973), British Columbia and Alberta, east to Churchill, Manitoba (Wayne 1959) and the northern coast of Ontario (Oughton 1948), and south in the United States in New Mexico, Arizona, Colorado, Wyoming, Kansas, Iowa, Illinois (Pilsbry 1948, Karlin 1961), and Washington (Branson 1977). Distribution: Currently this species is only known from the southern Columbia Basin in British Columbia, but it may eventually be discovered elsewhere at higher elevations. Notes: North American populations of this snail were long known as Columella alticola (Ingersoll, 1875), but Forcart (1959) combined C. columella and C. alticola into one species. He and Bequaert & Miller (1973) retained alticola as the North American. Name: Genus and specific names meaning "a column." Records: Tobacco Plains* (49°02'N, 115°06'W) (Whiteaves 1905; Berry 1922); E shore of Kootenay Lake, near boat launch S of ferry, Kootenay Bay (49°40.4'N, 116°52.3'W) (Forsyth Coll. 97-097-1094); along 2nd Avenue, 200 m SW of First Street East, Field (51°23.75'N, 116°29.3'W) (Forsyth Coll. 98-091-3071); Field (51°24'N, 116°29'W) (Berry 1922, Pilsbry 1948). View the map. *Whiteaves reported "Sphyradium edentulum"
from Tobacco Plains; Berry later reidentified the specimens as Columella
alticola. Columella edentula (Draparnaud,
1805): Toothless Column
Description: Shell small (height 2.5 mm); subcylindric and a little tapering; brown, with a silky lustre; spire high; apex blunt; whorls convex and numbering about 5 or 6; last whorl always larger than the penultimate whorl; periphery rounded; suture deep; teleoconch with irregular, wrinklelike, rather low, axial striae; aperture ovate and without denticles; outer unthickened and unexpanded; sinulus and crest absent; umbilicus small. Similar Species:C. columella. Small juveniles of C. edentula resemble Punctum in size and shape except for a more angular periphery and more rapidly enlarging whorls. The undeveloped shells of juvenile Vertigo may be difficult to separate from C. edentula. Habitat:Under logs, dead wood, and on vegetation, and in leaf litter. Range: Aleutian Islands, Alaska, east to Labrador (Dall 1905) south to New Jersey, Pennsylvania, Iowa, Montana, and Oregon; Alabama (Pilsbry 1948). In the Palearctic realm, widespread, from Iceland to Japan (Bequaert & Miller 1973). Distribution: Common and widespread throughout the province. Notes: North American populations are sometimes considered specifically distinct from C. edentula of Europe and are called Columella simplex Gould, 1841. Name: Species name meaning toothless, likely named in contrast to Vertigo and other toothed members of the family. Records: Summit Creek, Blazed Creek Rest Area,
Hwy 3, Salmo-Creston Highway (49°08.03'N, 116°47.85'W) (RBCM
998-00267-002); Schroeder Creek, near highway 31, N of Kaslo (50°01.95
N, 116°54.55'W) (RBCM 998-00263-007); W of snow sheds, Glacier
National Park (circa 51°15.5'N, 117°28'W) (Staatliches
Museum für Naturkunde Görlitz); Redgrave Rest Area, Hwy
1 between Roger's Pass and Golden (51°29.54'N, 117°16.18'W)
(RBCM 998-00274-004).
In some species of this genus, numerous form, varietal and subspecies names have been used for shells having additional or fewer denticles than typical, but the number of denticles (and often sculpture or strength of the crest) is assumed to be variable and form names and unqualified subspecies are not considered here. Named forms or 'subspecies', which are or could be applied to British Columbia material, are listed and defined under each species for reference. Identification is difficult in this genus, which is in need of revision. In place of a key, the most distinctive characters of the four species of Vertigo known from the Columbia Basin are presented in the following table (see the above figure for denticle nomenclature and their relative positions):
Comparison of the four species of Vertigo known from the Columbia Basin, British Columbia. Vertigo elatior
Sterki, 1894: Tapered Vertigo
Redrawn after Pilsbry 1948 Description: Shell small (height, 2.1 mm); subovate; spire with sides somewhat convex; whorls conves and numbering about 5; periphery rounded; suture deep; aperture irregularly subovate, with 5-7 (usually 5) denticles (Lp, Lc, Ls, Pu and Pl present; La occasionally present; Ps often present); sinulus prominent, turned inward to form a point; crest usually weak. (Specimens of this species have not been seen. The description is based on Pilsbry [1948].) Similar Species: V. ovata is less conical in form and has additional denticles. Habitat: Not reported for British Columbia. Range: Ontario and Maine, west to Montana and Field, British Columbia; New Mexico (Pilsbry 1948). Distribution: Known in British Columbia only from Field (Vanatta 1906; Pilsbry 1948). Name: Genus name meaning "whorl". Species name meaning "high". Record: Field (51°24'N,
116°29'W) (Vanatta 1906;
Pilsbry 1948). View
the map.
Vertigo
gouldii (Binney, 1843): Variable Vertigo
Description: Shell small (height, 1.9 mm), subcylindric; reddish brown or brown; spire long, with straight or slightly convex sides; apex blunt; whorls 5, convex; periphery rounded; suture deep; teleoconch with sharp, close axial striae, especially on the middle whorls; aperture subovate, with 4-6 (usually 4 or 5) denticles (Lp, Lc, Pl and Pu present La occasionally present, Ls occasionally present); outer lip slightly thickened and slightly flared; sinulus slight or moderate; crest absent or weak to rather prominent; umbilicus very small, slitlike, or closed. Similar Species: Vertigo gouldii is smaller than V. modesta, with a stronger crest and sharper, more regularly striate. Habitat: Under logs, rocks, moss, lichen and fallen leaves. Range: Québec, Ontario and Prince Edward Island to Missouri, Kentucky, Tennessee and Alabama; Colorado; Utah; New Mexico; Montana; British Columbia; Arizona; Kansas; Illinois (Pilsbry 1948). (Combined range of Vertigo gouldii and all its named subspecies or forms.) Distribution: Widespread throughout mountainous regions of eastern and northern British Columbia, although previously recorded in the province only from the Rocky Mountains at Field (Vanatta 1906; Pilsbry 1948). Notes: Doubtfully distinct western 'subspecies' of V. gouldii have been distinguished by the presence and absence of certain apertural denticles. Vertigo gouldii coloradensis (Cockerell, 1891) has 4 denticles (Lp, Lc, Pu, Pl) and a crest that is not well-developed. V. g. basidens Pilsbry & Vanatta, 1900 has 5 denticles (Lp, Lc, Ls, Pu, Pl), and a crest that is rather broad and sometimes prominent. V. g. arizonensis Pilsbry & Vanatta, 1900 has 5 denticles (Lp, Lc, La, Pu, Pl), and a crest that is very weak, and V. g. inserta Pilsbry 1919 has 6 denticles (Lp, La, Lc, Ls, Pu, Pl). Populations may consist of a single form or a mixture of forms. Name: Species name in honour of Augustus Addison Gould (1805-1866), malacologist and Boston physician. Records: Crowsnest Pass
Rest Area (49°39.06'N, 114°41.76'W) (RBCM 998-00297-003);
Hunter Creek Forest Recreation Site, along Kicking Horse R., ESE
of Golden (51°15.95'N, 116°44.69'W) (Forsyth Coll. 98-092-3300);
Along 2nd Avenue, 200 m SW of First Street East, Field (51°23.75'N,
116°29.30'W) (Forsyth Coll. 98-091-3074); Field (51°24'N,
116°29'W) (Vanatta 1906;
Pilsbry 1948); Sherbrooke
Trail head, N of Wapta Lake, Yoho National Park (circa 51°26.4'N,
116°21.5' W) (Forsyth Coll. 98-090-3387). View
the map.
Vertigo
modesta (Say, 1824): Cross Vertigo Description: Shell small (height, 2.5 mm), subcylindric, glossy; reddish brown or brown; spire long, with slightly convex sides; apex blunt; whorls 4½-5½, convex; periphery rounded; suture deep; teleoconch with fine, irregular, weak to strong axial striae, which are more distinct on the middle whorls; aperture subovate, regularly with 4-5 (typically 4) denticles (Lp, Lc, Pu and Pl regularly present; La sometimes present) or with various or all denticles absent; outer lip rather thickened, scarcely flared; sinulus absent or only a slightly flattened area on the outer lip; crest weak or moderately strong; umbilicus very small, slitlike or closed. Similar Species: Some forms of V. gouldii with only 4 denticles or with 4 denticles and an angular lamella may be mistaken for V. modesta. V. gouldii is smaller, however, with stronger and more regular sculpture. A subcolumellar plica is never present in V. modesta. Habitat: In British Columbia, V. modesta has been found living under rocks, leaves and moss. Range: Holarctic: in North America from New England west to California and northward (Dall 1905); Aleutian Islands (Hanna 1925); in Europe, known from Norway, Finland, Sweden, Switzerland, Bavaria and Iceland (Kerney & Cameron 1979). Distribution: Vertigo modesta is particularly widespread in the northwest and north-central interior of the province. It was reported from Field by Vanatta (1906). Notes: Specimens bearing an angular lamella (as in figure above) have been given the name Vertigo modesta parietalis (Ancey, 1887). These often occur with typical V. modesta. Name: Species name meaning "unassuming". Records: Cummings Creek,
N of Sparwood (49°46.32'N, 114°54.95'W) (RBCM 998-00293-005);
Lake Revelstoke, ½ km distant from Mica Dam (51°03.81'N,
118°33.42'W) (RBCM 998-00259-001); Field (51°24'N, 116°29'W)
(Vanatta 1906; Pilsbry
1948); Redgrave Rest Area, Hwy 1 between Roger's Pass and Golden
(51°29.54'N, 117°16.18'W) (RBCM 998-00274-003) . Vertigo ovata Say, 1822: Ovate Vertigo
Description: Shell small (length, 2.5 mm), subovate; somewhat translucent; rather glossy; reddish brown; spire rather short with sides very convex; apex obtuse; whorls 4, convex; periphery rounded; suture deep; teleoconch with fine axial striae; aperture irregularly subovate, with 7-9 (usually 9) denticles (Lp, Lc, La, Li, Ls, Pu, Pl present; Pi and Ps usually present); outer lip unthickened but flared; sinulus prominent, sharply turned inward to form a point; crest prominent; umbilicus slitlike or closed. Similar Species: This species is similar to Vertigo binneyana Sterki, 1890, and V. elatior. V. ovata is easily recognised by the large number of denticles around the peristome, its very much ovate form, and well-developed crest and sinulus. Habitat: Marshes and other wet places along the edges of waterways under decaying vegetation, leaf litter and logs. Range: Ungava Bay, northern Québec, south to the Florida Keys and the West Indies; in the west from Kodiak and Tigalda Islands, Alaska, south to Utah and Arizona (Pilsbry 1948; Bequaert & Miller1973); perhaps in Sonora, Mexico (Naranjo-García 1991). It has been introduced to New Zealand (Barker1982). Distribution: Widespread in the province, both inland and on the coast. Name: Species name describing the egg-shaped shell. Records: Creston Valley
Wildlife Management Area (49°07.19'N, 116°37.82'W) (RBCM
998-00282-003); Parson Bridge, Hwy. 95, S of Golden, near branch
of Columbia River (51°03.85'N, 116°38.77'W) (RBCM 998-00273-002).
View the map. Juvenile pupillids not identified to species:
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