Hemibagrus furcatus, a new species of bagrid catfish (Teleostei: Siluriformes) from Sabah, East Malaysia

Abstract

Hemibagrus furcatus, new species, is described from the Segama River drainage in Sabah, northeastern Borneo. It is similar to H. baramensis and H. sabanus in having the combination of a relatively short body with 43-45 vertebrae and a long adipose fin of more than 20 %SL spanning most of the postdorsal distance. It can be differentiated from congeners in having a unique combination of the following characters: head width 18.3-19.5 %SL, length of caudal peduncle 18.8-20.7 %SL, depth of caudal peduncle 9.4-10.3 %SL, length of adipose-fin base 21.2-26.3 %SL, dorsal to adipose distance 6.3-8.6 %SL, absence of a dark midaxial streak, 4-7 serrations on the dorsal spine, bifurcated serrae on the pectoral spine, upper lobe of the caudal fin rounded posteriorly, dorsal fin without an extended second ray, with broader membranes and allowing the fin to be spread wider, giving a more rounded appearance.