Great Pond Snail (Lymnaea stagnalis) Breeding Guide

Lymnaea stagnalis is a simultaneous hermaphrodite that lays gelatinous egg masses underwater on plants and glass. It is cold-tolerant and prized in neuroscience for its large neurons.

Overview

Lymnaea stagnalis is a large pulmonate pond snail of the family Lymnaeidae, with a tall conical shell 45 to 60 mm high bearing 4.5 to 6 weakly convex whorls. It is found across the temperate zones of North America, Europe and Asia, reaching northern Norway and montane sites up to 1,700 metres, and feeds on plant matter and algae.

Sexing

The species is a simultaneous hermaphrodite that can mate in either the male or the female role, but performs only one role per copulation. It shows a Coolidge effect, performing more inseminations in larger groups and preferring novel over familiar partners, so group keeping encourages reproduction.

Egg-laying / Reproduction

Eggs are deposited in gelatinous egg masses attached underwater to aquatic plants and other firm surfaces. Because the species is cold-tolerant and a hardy generalist, it breeds readily under aquarium conditions without an air gap, since reproduction takes place fully submerged.

Juvenile Care

Juveniles hatch directly from the gelatinous masses as miniature snails and graze immediately on algae and plant matter, requiring no special care. The species functions as an aquarium cleaner, consuming algae and organic debris, though it also eats soft plants.