Physella acuta

Physella acuta, also known as the European physa, tadpole snail, sewage snail, bladder snail, or acute bladder snail, is a species of small, air-breathing freshwater snail of the family Physidae. It originates from North America and was first described in 1805 by Jacques Philippe Raymond Draparnaud based on a specimen found in France. Like other physids, P. acuta presents a sinistral (left-coiling) shell as well as a unique set of muscles called the physid musculature that allows it to rapidly twist the shell as a defence mechanism.

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