Freshwater Pond Snails
Some facts about pond snails
Introducing Lymnaea stagnalis, the Great Pond Snail: a diligent and hardy resident of ponds and ditches popular with pond-owners and researchers in neurology
- The common name for Lymnaea stagnalis is the Great Pond Snail
- The zoological taxonomy is:
- Kingdom: Animalia
- Phylum: Mollusca
- Class: Gastropoda
- Group: Pulmonata
- Family: Lymnaeidae
- Genus: Lymnaea
- The Great Pond Snail is widespread in England, but is rare or absent in Northern England, Scotland and Wales. It is also found in Central Europe and in Canada
- Lymnaea Stagnalis can reach ages of 6 or 7 years, although relatively few reach this age. Adult shells are typically from 40 to 60 mm in length
- Food is mainly algae and decaying organic matter. Some sources claim that larger snails can attack small pond fauna.
- Great Pond Snails are hermaphrodytes with one snail of the pair taking the male role and the other the female. Unlike some other hermaphrodyte snails they cannot simultaneously fertilise one another, nor can they fertilise themselves.
- Eggs are laid in thin strands of clear jelly on rocks, water-plant leaves and other surfaces. The eggs are in a stggered double-file for larger snails, or single-file for smaller snails. The snails become visible as tiny black dots after a few days and hatch in approximately three weeks (depending on temperature)
- Lymnaea Stagnalis have lungs (are pulmonates) and so are able to breathe as well as to extract oxygen from the water through hair-like cilia on their tentacles. This allows them to survive in oxygen-poor environments such as algae-laden ponds by surfacing to breathe. In winter when the surface is frozen they burrow in the mud and remain dormant.
- Lymnaea are commonly used in laboratories to study learning and how it affects the central nervous system.