|Description: Medium-sized spider fully adapted for an aquatic life-style. Carapace pale to dark yellowish brown. Abdomen with dense pubescense appearing velvet-grey on land. But when in water, air is trapped around the abdomen giving it a silvery appearance. Legs coloured as carapace. Legs III and IV are furnished with long fine hairs that aid in swimming. These swimhairs are easily seen with a lens when the spider is examined in a tray with water, and identifies both immatures and adults. The species is one of very few spider species where the male usually is larger than the female. They build a retreat in the form of an underwater diving-bell, which is kept filled with air collected at the surface. The species has a reputation of being able to deliver a painful bite. Size: Female 8-12 mm; male 10-15 mm. Maturity: All year. Habitat: Ponds, streams with little current and shallow lakes, usually where there is well-developed aquatic vegetation. Range: Austria, Belarus, Belgium, Bosnia/Herzegowina, Bulgaria, Croatia, Czech Republic, Denmark, Estonia, Finland, France (Mainland), Germany, Great Britain (Mainland), Great Britain (Northern Ireland), Hungary, Ireland, Italy (Mainland), Latvia, Liechtenstein, Lithuania, Macedonia, Moldova, Netherlands, Norway (Mainland), Poland, Romania, Russia (Central European), Russia (Eastern European), Russia (Kaliningrad Region), Russia (Northern European), Russia (NW. European), Russia (Southern European), Slovakia, Slovenia, Spain (Mainland), Sweden, Switzerland, Ukraine, Yugoslavia (van Helsdingen 2009.1). Global range: Palearctic (Platnick 10.0).