Hydrophilus cavisternum ( Bedel, 1891 )

Hendrich, Lars & Balke, Michael, 2004, Aquatic Coleoptera Of Singapore: Species Richness, Ecology And Conservation #, Raffles Bulletin of Zoology 52 (1), pp. 97-145 : 128-129

Hydrophilus cavisternum ( Bedel, 1891)

( Fig. 30 )

Stethoxus cavisternum Bedel, 1891: 310 .

Hydrous cavisternum (Bedel) - Zaitzev, 1908: 364.

Hydrophilus cavisternum (Bedel) - Gentili et al. 1995: 212; Hansen, 1999: 228, and references therein.

Material examined. – 1 specimen – Other areas - 1 ex., Confederate Estate, July1915, “ P. de Fontaine Coll. ” ( ZRC) .

Distribution. – China [Hainan] (d’Orchymont, 1935), Laos, Cambodia, Vietnam, Thailand, West Malaysia, Indonesia [Java] ( Knisch, 1924b; Hansen, 1999) and New Guinea [Irian Jaya, in coll. Hendrich]. Singapore!

Ecology. – The species is living in various types of perennial standing and slow-flowing waters, such as swamps, ponds, paddy fields, fish ponds, shallow lakes and ditches. The habitat must be rich in detritus and submerged vegetation. Hydrophilus cavisternum is frequently attracted to light and is one of the most common larger hydrophilids in Southeast Asia.

Remarks. – The species has become extinct in Singapore. In Thailand [Pak Chong, Chaiyaphum and Bangkok] different species of this genus are sold as food throughout the year ( Chen et al., 1998; Fritzsche & Gitsaga, 2000).

Figures

Figs. 24-30. 24. Cybister sugillatus Erichsin, 1834 (Fam. Dytiscidae, 22.0 mm); 25 Hydrocanthus indicus Wehncke, 1876 (Fam. Noteridae, 4.5 mm); 26. Spercheus stangli Schwarz & Barber, 1917 (Fam. Spercheidae, 4.2 mm); 27. Berosus fairmairei Zaitzev, 1908 (Fam. Hydrophilidae, 4.5 mm); 28. Amphiops mater sumatrensis (Sharp, 1873) (Fam. Hydrophilidae, 3.5 mm); 29. Helochares pallens (MacLeay, 1825) (Fam. Hydrophilidae, 3.1 mm);30. Hydrophilus cavisternum Bedel, 1891 (Fam. Hydrophilidae, 32.0 mm).