Land Snails

Photo(s): Allogona profunda (Say, 1821) © John Slapcinsky; Allogona profunda shell © Larry Watrous
Illustration © Kathy Schmidt from her series "Land Snails of New York State"

Click to enlarge.

Allogona profunda (Say, 1821)

Family: Polygyridae
Common name: Broad-banded Forestsnail

Identification
Width: 25-33 mm
Height: 15-17 mm
Whorls: 5+

This snail has a robust heliciform shell with a wide umbilicus, a reflected peristome, and a broad reddish stripe. The stripe may be absent from long-dead shells, but the big, flattened shell with a “bump” of a basal lip tooth is easily recognized. The animal's body is a medium to light gray.

Ecology
Allogona profunda is usually found in leaf litter in rich forests on floodplains or hilly terrain. Fieldwork in an oak-maple forest in Illinois found that overwintering A. profunda were completely inactive for nearly six months, not responding to brief periods of warm weather (Blinn, 1963). In the active season, snails moved to an area of a well-rotted log. In a second year of study, individuals returned to their previous overwintering site. Immature animals usually grew to maturity in their second active season, less often their third.

Taxonomy
Synonyms for A. profunda include Helix profunda, H. richardii, Mesodon profunda, Polygyra profunda, P. p. alba and unicolor, P. p. efasciata, P. p. strontiana, and P. p. pleistocenica.

Distribution
This species is found in the Midwestern states and in the interior of the Mid-Atlantic, though its distribution is patchy. Its range reaches north to New York (though it is introduced there) and Minnesota, and south to Tennessee and North Carolina. It is presumed extirpated in states further to the south - Louisiana, Arkansas, and Mississippi (NatureServe, 2012). In Virginia it is found in mostly western counties.

Conservation
NatureServe Global Rank: G5.

 

Ken Hotopp, Meegan Winslow 8/2012

Range Map