Virginia Land Snails
Photo(s): A Helicodiscus lirellus shell from Rockbridge County, Virginia, by Jeffrey C. Nekola ©. Live animal by Ken Hotopp ©.
Click photo(s) to enlarge.
Helicodiscus lirellus Hubricht, 1975
Common name: Rubble Coil
Width: 4-5 mm
Height: 1.5-2.0 mm
The whorls of the disk-like Helicodiscus lirellus are flattened so that almost no spire is visible. Coarse growth wrinkles are intersected by fine spiral lirae. The final whorl of H. lirellus bears one or two sets of teeth – each set has a long, radial lamella on the outer wall, another on the basal wall, and a third on the parietal wall. The parietal lamella is cupped, facing toward the aperture.
Separate parietal teeth, rather than a single, larger lamella with a notch, distinguish this animal from H. multidens. Its dished parietal lamella is unlike the simpler parietal tooth of H. triodus, and it lacks the tiny hair-like projections of H. diadema. The animal is white and apparently blind.
Recent fieldwork shows that Helicodiscus lirellus is found among leaf litter and limestone stones or talus, or in rich shale scree, upon steep, forested slopes (K.P. Hotopp. J.C. Nekola, T.A. Pearce, pers obs). These slopes are associated with certain rivers in the upper James River watershed, including the Maury River and Kerr’s Creek.
There are no synonyms.
Helicodiscus lirellus is known only from Rockbridge County.
NatureServe Global Rank: G1
NatureServe State Rank: S1
Virginia wildlife action plan: Tier I
State Status: Endangered
Ken Hotopp, Meegan Winslow 11/2012