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Family: Polygyridae
Common name: Spruce Knob Threetooth
Discovery: Hubricht, 1958
Identification
Width: 12-15 mm
Height: 7.5-9.5 mm
Whorls: 5
The shell of Triodopsis picea is a depressed-globose shape, with coarse radial striae. The whorls gradually increase in size, and all but the nuclear whorl are covered with papillae. The reflected lip is guttered behind. The umbilicus, as in T. juxtidens, is small and open, and the denticles are smaller than those in T. fraudulenta. The parietal tooth is high, straight, and long; the basal tooth is narrow; and the tooth on the outer lip is broad and blunt.
Ecology
This snail is found in leaf litter and near rocks and logs, at higher elevations in rocky woods, often in mixed conifer and hardwood stands. Its common name is for its type locality on West Virginia’s highest mountain. In western Maryland it lives at low densities on cool hemlock and yellow birch slopes or stream valleys (Hotopp, pers obs).
Taxonomy
There are no known synonyms.
Distribution
The uncommon T. picea is a central Appalachian Mountain endemic, living in southwest Pennsylvania, western Maryland, West Virginia, and Virginia. In Virginia, it is known only from Highland County.
Conservation
NatureServe Global Rank: G3
NatureServe State Rank: S1
Virginia’s wildlife action plan: Tier II
