Land Snails

Photo(s): Live Xolotrema denotatum showing the very dark-colored animal, (shell apex is deformed) © Bill Frank. Images of shell © Dan Dourson.

Click photo(s) to enlarge.

Xolotrema denotatum (Férussac, 1821)

Family: Polygyridae
Common name: Velvet Wedge

Identification
Width: 18-26 mm
Height: 10-14 mm
Whorls: 5+

Xolotrema denotatum has an exceptional shell – large, dark, and fuzzy with a striking flared lip. The outer coat of its shell is covered with fine, hair-like processes, giving it a moleskin-like texture, and it is often draped with cobwebs that provide a sort of camouflage. Old shells lose this fine coating as it is part of the outer protein coat, or periostracum. The lip is concave and has elongate parietal and basal teeth, and a shorter, blunt palatal tooth. The umbilicus is usually closed and the animal itself is very dark-colored.

Ecology
This species is often found near or upon big logs and snags, sometimes on steep, damp slopes where large trees have fallen. It may also occasionally be found on floodplains (Hubricht, 1985).

Taxonomy
Synonyms for X. denotatum are Helix denotata, Triodopsis denotata, Triodopsis notata, and Xolotrema denotata.

Distribution
This animal lives in upland forests from Vermont, southeastern Canada, and Michigan, south to eastern Arkansas, northern Mississippi, and Alabama. In Virginia it is mainly in the western counties but is also reported from Fairfax County (Hubricht, 1985).

NatureServe Global Rank: G5
NatureServe State Rank: S3S4

 

Ken Hotopp, Meegan Winslow 11/2012

Range Map (click to enlarge)