- Source: Spercheus
Spercheus is a genus of aquatic beetles which are placed in a family of their own, Spercheidae within the Hydrophiloidea. About 20 species are known from around the world except the Nearctic with the majority being from the Oriental and Afrotropical Realms.
All life stages are found in shallow still water with rich vegetation, which in some species includes temporary saline pools. Adults and larvae live attached to pieces of vegetation or debris, and also walk on the underside of the water surface. Air is held in a bubble on the underside of the body. The larvae feed on grazed detritus as well as drifting algae, dead organisms, and other organic refuse. The adults live as filter feeders on floating debris like decaying plant material and other decomposing organic remains. The adult females build a silken-egg case which they attach to their mid-tibiae and held by the hind legs, carried below the abdomen. These beetles were formerly placed in the family Hydrophilidae but are distinctive.
The front of the head is notched and the 7–9 segmented antenna has the terminal 3–4 segments club like and an enlarged fourth segment. The elytra are very convex and one or two abdominal segments may extend beyond the apex. They have 5 tarsal segments on all legs.
Possible fossils of Spercheus have been described from the Eocene aged Bembridge Marls of the Isle of Wight, England. The extinct genus Prospercheus from the Late Jurassic of Shar-Teg, Mongolia, has also been considered a close relative of Spercheus, and also placed in Spercheidae.
Species
Spercheus belli Champion, 1919
Spercheus burgeoni Orchymont, 1929
Spercheus cerisyi Guérin Méneville, 1842
Spercheus crenulatus Fairmaire, 1893
Spercheus emarginatus (Schaller, 1783)
Spercheus fimbriicollis Bruch, 1915
Spercheus gerardi Orchymont, 1929
Spercheus halophilus Archangelsky, 2001
Spercheus hanseni Hebauer, 1990
Spercheus hovanus Fairmaire, 1903
Spercheus humeralis Régimbart, 1906
Spercheus platycephalus MacLeay, 1825
Spercheus senegalensis Castelnau, 1832
Spercheus siamensis Hebauer, 1990
Spercheus spangleri Hebauer, 1990
Spercheus stangli Schwarz & Barber, 1918
Spercheus stasimus Orchymont, 1937
Spercheus wattsi Hebauer, 1999
References
External links
Australian Freshwater Invertebrates
Tree of Life