Dineutus (Spinosodineutes) spinosus ( Fabricius, 1781 )

Hendrich, Lars & Balke, Michael, 2004, Aquatic Coleoptera Of Singapore: Species Richness, Ecology And Conservation #, Raffles Bulletin of Zoology 52 (1), pp. 97-145 : 123

Dineutus (Spinosodineutes) spinosus ( Fabricius, 1781)

Gyrinus spinosus Fabricius, 1781: 298 .

Dineutus (Spinosodineutes) spinosus : Ochs, 1929: 401, 1930a: 10; Brinck, 1981: 353; Vazirani, 1984: 16, and references therein; Balke et al., 1999: 326.

Material examined. – 1 specimen - Central catchment area - 1 ex., stream of MacRitchie Reservoir, 20 Apr.1994, NS 123a, coll. K. L. Yeo et al. ( ZRC) .

Distribution. – India, Bangladesh, Myanmar, Thailand, Laos, Vietnam ( Vazirani, 1984); Malaysia, Indonesia: Sumatra ( Ochs, 1929) and Borneo (Mazzoldi, in litt.); Singapore ( Ochs, 1930a; Balke et al., 1999).

Ecology. – The single specimen was collected from a relatively clear, slow-flowing and oxygen-rich, well-shaded part of a stream in the Central catchment area. In West Malaysia this species is common in medium-sized streams with slow-flowing water in the forest. It is rare in Singapore as all streams are shallow and small. Often found in association with Orectochilus productus .

FAMILY GROUP HYDROPHILOIDEA

FAMILY SPERCHEIDAE

This is a rather small family with 17 species worldwide which all belong to the genus Spercheus . Most species described are from the Ethiopian and Oriental regions. Just four species are reported from Southeast Asia ( Hebauer, 1997; Hansen, 1999). Most species have coarsely punctuated and costate elytra. Spercheidae inhabit stagnant, often weedy pools, ponds, swamps and paddy fields. Adults and larvae have been reported to walk on the underside of the surface film. The life history of most species is still unknown, except for the central European S. emarginatus ( Hansen, 1987) .