A revision of the South-east Asian catfish genus Silurichthys

Abstract

The taxonomy of the catfish genus Silurichthys is revised, and eight species are now recognized. A neotype is designated for S. hasseltii. Two new species are described: S. gibbiceps from the Barito basin in southern Borneo and S. marmoratus from north-western Borneo. Silurichthys leucopodus Fowler, 1939, is considered a subjective junior synonym of S. schneideri Volz, 1904. The extent of the gape and the relative positions of the dorsal and pelvic fins show considerable infraspecific variation and are of little taxonomic value. The number of anal-fin rays is useful if used with other meristic data such its the number of vertebrae. Colour varies infraspecifically as individuals become paler anti less mottled at night, but can still be used as a secondary character in separating some species. The head and caudal fin shapes are useful discriminating characters. Mature males are smaller than females and have prominent posterior serrae on the pectoral spine and articulated segments of the first pectoral-fin element. The shape and number of these serrae are also diagnostic for some species.