Anisus leucostoma is a European species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of small air-breathing freshwater snail

Freshwater snail

A freshwater snail is one kind of freshwater mollusc, the other kind being freshwater clams and mussels, i.e. freshwater bivalves. Specifically a freshwater snail is a gastropod that lives in a watery non-marine habitat. The majority of freshwater gastropods have a shell, with very few exceptions....

, an aquatic

Aquatic animal

An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that...

 pulmonate gastropod in the family Planorbidae

Planorbidae

Planorbidae, common name the ramshorn snails or ram's horn snails, is a family of air-breathing freshwater snails, aquatic pulmonate gastropod mollusks....

, the ram

Ovis

Ovis is a genus of mammals, part of the goat-antelope subfamily of the ruminant family Bovidae. Its five or more highly gregarious species are known as sheep...

's horn snails and their allies.

Synonyms

According to Glöer (2002) Anisus septemgyratus (Rossmässler, 1835) is a junior synonym of Anisus leucostoma (Millet

Millet

The millets are a group of small-seeded species of cereal crops or grains, widely grown around the world for food and fodder. They do not form a taxonomic group, but rather a functional or agronomic one. Their essential similarities are that they are small-seeded grasses grown in difficult...

, 1813).

Shell description

The shell of this species is about 8 mm in maximum dimension, usually planispiral and tightly coiled, with a white rib in the aperture.

Distribution

This species occurs in countries and islands including:

• Czech Republic - near threatened (NT)
• Germany
• Slovakia
• British Isles, Great Britain, Ireland