Land Snails

Photo: Aperture view of Triodopsis alabamensis © Bill Frank.

Click photo to enlarge.

Triodopsis alabamensis (Pilsbry, 1902)

Family: Polygyridae
Common name: Alabama Threetooth

Identification
Width: 11-12 mm
Height: 5-7 mm
Whorls: 6+

The low, dome-shaped shell of Triodopsis alabamensis has whorls that are very closely coiled around an open umbilicus. The final whorl of the shell descends, so at the aperture it is attached to the previous whorl about a third of the way down from the top. The periphery of the aperture is dish-shaped, with the top edge in a nearly horizontal plane. The shell has three teeth, like many of its genus, with a pronounced and somewhat curved parietal tooth on the body whorl. The palatal lip tooth is bent inward.

Ecology
This snail prefers pine or oak forests, and is usually found in leaf litter and around logs (Coney et al, 1982; Hubricht, 1985).

Taxonomy
T. alabamensis has also been known as Polygyra alabamensis, P. vannostrandi alabamensis, and Triodopsis vannostrandi alabamensis.

Distribution
T. alabamensis inhabits the southern Appalachian Mountains of Alabama, South Carolina, Georgia, Tennessee, and Virginia (Hubricht, 1985). Virginia’s population is an apparent disjunct in Pittsylvania County (though not reported in Hubricht, 1950).

Conservation
NatureServe Global Rank: G4
NatureServe State Rank: SNR

 

Meegan Winslow, Ken Hotopp 11/2012

Range Map (click to enlarge)