Water spider
Argironeta aquatica (Clerck, 1757)
Order Araneae
Family Cybaeidae
Conservation status: in Bulgaria: Critically endangered CR.
General distribution. Europe, Asia and Japan.
Distribution and abundance in Bulgaria. Reported from the marshes of Radomir, Dragoman, Straldzha and Boyana [1, 2, 3, 4]. There are no data of its abundance.
Habitats. It inhabits stagnant or slowly changing water basins overgrown with waterweed and other water vegetation.
Biology. It leads an underwater way of life. It is found on plants close to the water when preparing for diving. In the water it appears silvery, because of the air that embraces the mossy small body. Under the water it builds a small dome of a network of web-like matter, fixes it onto the stem of some plant and starts filling it with air. It goes onto the surface many times, shows the edge of the small belly, scoops air with the hind legs, dives and unloads it into the underwater dome. A predator feeding on water insects, their larvae and even tadpoles. It spends its whole life in the underwater dome where it breeds and dies.
Similar species. None.
Negative factors. Loss and degradation of the major habitats as a result of drying up water areas; infrastructure development; tourism.
Conservation measures taken. None.
Conservation measures needed. Maintenance and preservation of stagnant water habitats; specification of the protection status for water basins where the Argironeta aquatica has been found. Studies on the biology and ecology of the population; monitoring.
References. 1. Drensky, 1913; 2. Jurinich & Drensky, 1917; 3. Drensky, 1936; 4. Deltshev & Blagoev, 2001.
Author: Christo Deltshev
