Orectochilus (Patrus) oxygonus Régimbart, 1907

Hendrich, Lars & Balke, Michael, 2004, Aquatic Coleoptera Of Singapore: Species Richness, Ecology And Conservation #, Raffles Bulletin of Zoology 52 (1), pp. 97-145 : 122

Orectochilus (Patrus) oxygonus Régimbart, 1907

Orectochilus oxygonus Régimbart, 1907: 203 ; Ochs, 1927a: 2; Balke et al., 1999: 326.

Material known. – Number ? - « Singapour » ( Régimbart, 1907). Not seen. – 106 specimens - Central catchment area – 13 ex., Seletar Reservoir, 16-27 May.1994 [NS 134C, 137A,140, 143A]

( CPM, ZRC); 5 ex., Upper Peirce Reservoir , 24 May.1993, NS92, coll. C.Y. Chang et al. ( ZRC) ; 18 ex., MacRitchie Reservoir , May1994, NS122A & 178, and 7 Jun.1995, NS 183 ( CPM, ZRC) ; 25 ex., Nee Soon Swamp Forest , May1994, NS126A & 127 ( CPM, ZRC) ; 45 ex, Chesnut Drive 5-10 May.1994 [NS 128B, 130, 154 &155] ( ZRC) .

Distribution. – Southernmost part of West Malaysia, Johor State (Mazzoldi, in litt.) and Singapore ( Régimbart, 1907; Ochs, 1927a; Balke et al., 1999).

Ecology. – A common species in forest streams. Most specimens were collected in clear and oxygen rich water in well-shaded small streams and edges of reservoirs in the Central Catchment Area. Mazzoldi (in litt.) has collected some specimens from a very small, completely shaded stream in thick secondary forest in Johor (West Malaysia) but this species seems to be common only in Singapore.

Remarks. – Singapore is the type locality of O. oxygonus .