Maurice Kottelat

Abstract. Barbucca heokhuii, new species, is described from the Kahayan drainage in central Borneo. It is distinguished from the other species of the genus by its miniature size (the largest known specimen is 21.5 mm SL), a truncate to rounded caudal fin, an incomplete lateral line, and a distinctive colour pattern made, among others, of five pairs of irregular bars on the flank, narrower than interspaces, many of which may be dissociated into several small blotches. It occurs in syntopy with B. diabolica. Sexual dimorphism is reported for the first time for a member of the family; in males, the 2nd to 4th branched pectoral rays are thicker than the others and with a patch of small tubercles along their posterior edge.

Key words. Cobitoidei, loach, miniature fish, sexual dimorphism, black water, peat swamp forest

Read article here: RBZ-2025-0005