FRESH-WATER FISHES FROM THE HEADWATERS OF THE BELALONG-TEMBURONG RIVER SYSTEM, BRUNEI-DARUSSALAM, BORNEO

Forty four species belonging to 10 families and 30 genera were collected from the headwater streams within the primary dipterocarp forest of the Belalong-Temburong river system, upstream from the confluence (Kuala Belalong) and within the Batu Apoi Forest Reserve, Temburong District, Brunei Darussalam. All but three species are new records for Brunei Darussalam. Twenty three (52%) of these are endemic to Borneo, with 15 belonging to the family Balitoridae. As with other streams in Southeast Asia, the fish fauna in the Kuala Belalong area is dominated by Cyprinoidea (three families, totalling 29 species) with the Balitoridae and Cyprinidae comprising 15 and 13 species, respectively. In the absence of data from the rest of Brunei, the ichthyofauna of the study area is North Bornean (sensu Inger & Chin, 1962) with western elements and resembles most closely to that of the western part of Sabah. Over 20 of the fish species recorded form the basis a subsistence fishery for the Iban longhouse population.