
KEY POINTS
- Rare 'German hairy snail' is now one of London's most threatened molluscs
- Conservation groups are mapping its habitat along the Thames to prevent extinction
- Fossil records suggest it has lived in Britain since the Ice Age, long before its 1980s discovery
The German hairy snail (Pseudotrichia rubiginosa) is a fingernail-sized mollusc known for the fine hairs covering its shell. These tiny hairs may help the snail retain moisture and keep its slime sticky enough to move along slippery riverside debris.