Clausilia bidentata

Clausilia bidentata, the two-toothed door snail, is a species of door snails, terrestrial pulmonate gastropod mollusks in the genus Clausilia belonging to the family Clausiliidae, all of which have a clausilium.

Clausilia bidentata
Clausilia bidentata var. crenulata
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Order:	Stylommatophora
Family:	Clausiliidae
Genus:	Clausilia
Species:	C. bidentata
Binomial name
Clausilia bidentata (Strøm, 1765)
Synonyms
Turbo Bidentatus Strøm, 1765[2] Clausilia nigricans Maton & Rackett, 1807

Subspecies

• Clausilia bidentata abietina Dupuy, 1849
• Clausilia bidentata bidentata (Ström, 1765)
• Clausilia bidentata crenulata Risso, 1826
• Clausilia bidentata moniziana Lowe, 1852

Distribution

This species is present in much of western Europe,^[1] including:

• Czech Republic - in Bohemia only
• Great Britain
• Ireland

Habitat

This species is commonly found under bark of trees or in crevices of rocks. The snails are often encountered when they are most active, at night during wet weather, at which time they often climb up trees and feed on lichens.

Ecology

It selectively grazes on calcareous-rock lichens, particularly the crustose lichen species Verrucaria nigrescens.^[3]

Description

The shell of this snail is a small and cylindrical snail, very high-spired and narrow. The shell length reaches 10–11 millimetres (0.39–0.43 in). The shell is dark brown with noticeable spiral ribs, slight longitudinal grooves, and a horny operculum.

Gallery

Clausilia bidentata var. crenulata – Close-up

Lateral view of the shell of Clausilia bidentata crenulata.

Clausilia bidentata var. crenulata.

Clausilia bidentata var. crenulata, close-up.