Description: A small limpet-like, conical shell with a backwardly-directed curved apex. Very common and widespread in flowing water. 5-8 mm.

World Distribution: In Europe only absent from areas where flowing water is likely to freeze in winter, therefore not in central or northern Scandinavia. Distribution type probably Eurosiberian Southern-temperate (84), but the de-limitation of various southern and eastern forms which may be given independent species status is poorly known.

Irish Distribution: Abundant throughout except in polluted streams and rivers.

Ecology:

• A bottom living species ubiquitous in unpolluted running water of all kinds where it adheres to the sides of stones in moderate flows
• Also lives on stones in the wave zone of lakes
• Sensitive to pollution but is usually excluded from suitable habitat only by chronic pollution as it will normally recolonize lost territory after point-source incidents (Anderson, 1977).

Key Identification Features:

• A small, limpet-like shell with a conical, backwardly directed apex
• Shell with fine growth lines but lacking other ormament and fairly dull, pale brown
• Animal grey

Red list status:

• Least concern (lc).

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

iNaturalist: Ancylus fluviatilis at iNaturalist World Species Observations database.

GBIF data for Ancylus fluviatilis | Classification: Gastropoda, incertae sedis, Planorbidae, Ancylus

Thumbnails for genus Ancylus