Aquatic Coleoptera Of Singapore: Species Richness, Ecology And Conservation # Author Hendrich, Lars Author Balke, Michael text Raffles Bulletin of Zoology 2004 52 1 97 145 journal article 10.5281/zenodo.13244881 2345-7600 13244881 Chasmogenus abnormalis ( Sharp, 1890 ) Philydrus abnormalis Sharp, 1890: 351 . Helochares abnormalis ( Sharp, 1890 ) - Fernando, 1961: 23 ; 1964: 87 . Chasmogenus abnormalis ( Sharp,1890 ) - Hebauer, 1992: 68 ; Hansen, 1999: 174 , and references therein. Material examined. – 5 specimens – Central catchment area - 1 ex. , Nee Soon Swamp Forest , Fluorescent Light trap , 1930 – 2130 hrs., 22 May.1992 ( ZRC ) ; 2 ex. , Lower Pierce Forest , H.R. Light trap , 2130-2330 hrs., 4 Jun.1992 ( ZRC ) ; 2 ex. , Lower Peirce Reservoir , after the concrete water runoff, 22 Apr.1997 , 230a, coll. H. K. Lua ( ZRC ) . Distribution . – The most widespread species of the genus in the Oriental region. Sri Lanka , Thailand , Vietnam , Cambodia , West Malaysia , Indonesia [ Java , Sumatra , Sulawesi , Kalimantan], Philippines [Luzon], Taiwan and Japan ( Hebauer, 1992 ; Hansen, 1999 ). Singapore ! Ecology . – Some of our specimens were collected under lighted conditions. Like other species of the genus (Hendrich pers. observ.) it is most probably a lentic species, living in very shallow water at the edge of semi-shaded forest pools and puddles. The species has already been recorded from a light trap ( Fernando, 1961 ).