Description: A small, very tightly coiled shell of 7-8 whorls. The whorls overlap on the underside. Color mid brown but invariably coated with a dark brown matt deposit. Aperture flattened and enveloping the previous whorl. Widespread and common. 4.5-6 mm.

World Distribution: Found across Europe and Siberia to the Far East. Distribution type: Eurasian Wide-temperate (65).

Irish Distribution: Widespread and generally common except in the south-west, extreme west and north-west.

Ecology:

• This snail has a predilection for small, impoverished water-bodies, drains and marshy or peaty pools, also floodplain marshes
• It occurs only sparingly in larger water-bodies
• Seemingly tolerant of acidic conditions to a greater extent than other pulmonates except perhaps Radix balthica - often the only species present in drains or pools in and around raised bogs

Key Identification Features:

• A small, very tightly coiled flat shell of 7-8 whorls
• The whorls overlap on the underside producing a shallow umbilicus
• The aperture is a flat oval and follows the curvature of the previous whorl
• Shell light brown to olive-brown but invariably coated with a dark brown deposit

Red list status:

• Least concern (lc).

Distribution Map from NBN: Bathyomphalus contortus at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Bathyomphalus contortus at iNaturalist World Species Observations database.

GBIF data for Bathyomphalus contortus | Classification: Gastropoda, incertae sedis, Planorbidae, Bathyomphalus

Thumbnails for genus Bathyomphalus