Land Snails

Photo(s): From left to right: Vertigo perryi, Clinton SE, Kennebec County, Maine; Plymouth County, Massachusetts. Images © Jeffrey C. Nekola.

Click photo(s) to enlarge.

Vertigo (Alaea) perryi Sterki, 1905

Family: Vertiginidae

Identification
Height: 1.5-1.9 mm
Width: 1.0-1.1 mm
Whorls: 5

Taxonomy
Within the subgenus Alaea, Vertigo perryi shares with boreal North American V. ventricosa and northeast Asian V. kurilensis a small shell with irregular, weak striae and ovate-conical shape. It consistently differs from V. ventricosa shells in its more ovate shape, grayer olive-yellow color, silky luster from the presence of weak malleation and fine spiral lines on the shell surface, weaker lamellae development and a dark coloration of the apertural margin. These features remain constant across its range.

Ecology
Vertigo perryi is limited to moderately to highly acidic forested to open wetlands (Coles and Nekola, 2004; Nekola, 2008; Nekola and Coles, 2010). It can be abundant in dead leaf accumulations adjacent to sedge tussocks and may also ascend into living vegetation. Type Locality: Warwick, Rhode Island, U.S.A.

Taxonomy
There are no synonyms.

Distribution
While ranging in North America from northern Wisconsin to Newfoundland, V. perryi is most commonly encountered from areas bordering the Gulf of Maine and Cape Cod wetlands (Coles and Nekola, 2004; Nekola and Coles, 2010). While not yet reported from the southern Canadian Maritime provinces, it is to be expected from New Brunswick and southern Nova Scotia.

Conservation
NatureServe Global Rank: G3/G4, Vulnerable to Apparently Secure.

Jeff Nekola 9/2017

Range Map (click to enlarge)