Mollusks : Carnegie Museum of Natural History · Columella simplex appears similar to immature...

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Photo(s): Columella simplex shells may

vary in height, by Jeff Nekola ©.

Click photo(s) to enlarge.

Virginia Land Snails

Columella simplex (Gould, 1840)

Family: Vertiginidae

IdentificationHeight: ~2.1 mmWidth: ~1.1 mmWhorls: 5-­7

Columella simplex appears similar to immature Vertigo with its small, brown shells that are considerably tallerthan they are wide but which lack apertural lamellae. Adult shells are most easily distinguished from immatureVertigo by possessing at least 5 whorls. Immature Columella with fewer whorls in many cases cannot bedistinguished from immature Vertigo.

Columella “simplex” encompasses such a large variation of shell sizes, shapes, and shell surface sculpturesthat Pilsbry (1948), Oughton (1948), Hubricht (1985) and Nekola & Coles (2010) all suggest this name likelyrefers to a several-­species complex. Large forms in this complex that occur on limestone outcrops across thecentral and eastern states (Nekola, 2004) have been commonly confused with Columella columella in thesouthwestern USA (Bequaert and Miller, 1973;; Metcalf and Smartt, 1997).

EcologyAcross its range, C. simplex, as currently defined, is found in a wide variety of forested and open habitats,varying from subtropical to taiga, xeric to wet, and acidic to calcareous. In the north it is commonly foundclimbing on ferns and other herbaceous vegetation, up to a meter above the ground (in such situations leaf littersieving underestimates population size). In the south, however, it most commonly occurs in leaf litteraccumulations.

TaxonomySynonyms for this animal’s name include Pupa simplex and Columella edentula.

DistributionColumella simplex, as currently defined, ranges from central Quebec and Labrador south to southern Alabamaand Mississippi west to southern New Mexico and Arizona north to central Ontario, Manitoba, and Alberta andAnchorage, Alaska along the Pacific coast (Oughton, 1948;; Nekola & Coles, 2010).

In Virginia, this species has been observed from across most of the state. Although not currently reported fromthe southeastern counties, its presence in the adjacent coastal plain of North Carolina suggests that it ispresent but simply overlooked in this region.

NatureServe Global Rank: G5QNatureServe State Rank: S4

Jeff Nekola 9/2012

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