Anisus septemgyratus

Anisus septemgyratus is a species of air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails.

Taxonomy
Glöer (2002) considered Anisus septemgyratus (Rossmässler, 1835) as a junior synonym of Anisus leucostoma (Millet, 1813). Later Glöer & Meier-Brook (2008) used name Anisus septemgyratus again.

Horsák et al. (2013) consider Anisus calculiformis (Sandberger, 1874) as a synonym of Anisus septemgyratus.

Distribution
This species occurs in countries and islands including:


 * Czech Republic – in Moravia, critically endangered (CR)
 * Slovakia
 * Poland
 * British Isles

Description
The number of prostate diverticles ranges from 30 to more than 50.