Description: A flat-coiled shell of 4½ whorls. Similar to Anisus leucostoma but whorls broader and maximum width of the last whorl >25% of shell width. Status in Ireland uncertain. 6-8 mm.

World Distribution: Widespread in Europe, with a Eurasian Wide-temperate range (65).

Irish Distribution: Very uncommon in Ireland and possibly confined to the south and south-east. Not recorded recently and status uncertain.

Ecology:

• Characteristic of temporary water-bodies, like A. leucostoma, but probably with a more southerly range

Key Identification Features:

• Shell a flat coil of 4½ whorls
• Has broader and fewer whorls than A. leucostoma so that the last whorl is greater than 25% of the maximum shell width
• Aperture round but lacking an internal rib
• Internally, the number of diverticulae of the prostate gland are significantly fewer (10-15) than in leucostoma (20-25) (Glöer & Meierbrook, 2008)

Red list status:

• Data deficient.

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

iNaturalist: Anisus spirorbis at iNaturalist World Species Observations database.

GBIF data for Anisus spirorbis | Classification: Gastropoda, incertae sedis, Planorbidae, Anisus

Thumbnails for genus Anisus