Land Snails

Photo(s): Triodopsis juxtidens shell © Bill Frank. The parietal tooth points at or above the palatal tooth in this species.

Click photo(s) to enlarge.

Triodopsis juxtidens (Pilsbry, 1894)

Family: Polygyridae
Common name: Atlantic Threetooth

Identification
Width: 12-19 mm
Height: 6.5-10 mm
Whorls: 5+

This snail possesses a typical threetooth shell, with three tooth-like barriers in the aperture. The shell has a microsculpture of fine ridges and an open umbilicus on a depressed heliciform shell. It looks very similar to T. tridentata, but it can be distinguished by a parietal tooth that points at or above its palatal tooth, when viewed from the bottom.

Ecology
Triodopsis juxtidens commonly inhabits hilly, rich forests, sometimes on limestone. It can be found in leaf litter and under logs and rocks. It can also occasionally be seen in meadows, along roadsides, or on abandoned terrain in urban areas (Hubricht, 1985).

Taxonomy
T. juxtidens has also been known as Polygyra tridentata juxtidens, P. t. juxtidens, and Triodopsis tridentata juxtidens.

Distribution
Triodopsis juxtidens occurs in forests to the east of the Appalachian Plateau, but it is found farther west in New York, Pennsylvania, and some Mid-Atlantic states, including Virginia. However, it is not found in Virginia’s southwestern-most counties.

Conservation
NatureServe Global Rank: G5
NatureServe State Rank: S4S5

 

Ken Hotopp, Meegan Winslow 11/2012

Range Map (click to enlarge)