A REVISION OF THE SOUTH-EAST ASIAN CATFISH GENUS SILURICHTHYS

The taxonomy of the catfish genus Silurichthys is revised, and eight s pecies are now recognized. A neotype is designated for S. hasseltii. T wo new species are described: S. gibbiceps from the Barito basin in so uthern Borneo and S. marmoratus from north-western Borneo. Silurichthy s leucopodus Fowler, 1939; is considered a subjective junior synonym o f S. schneideri Volt, 1904. The extent of the gape and the relative po sitions of the dorsal and pelvic fins show considerable infraspecific variation and are of little taxonomic value. The number of anal-fin ra ys is useful if used with other meristic data such as the number of ve rtebrae. Colour varies infraspecifically as individuals become paler a nd less mottled at night, but can still be used as a secondary charact er in separating some species. The head and caudal fin shapes are usef ul discriminating characters. Mature males are smaller than females an d have prominent posterior serrae on the pectoral spine and articulate d segments of the first pectoral-fin element. The shape and number of these serrae are also diagnostic for some species. (C) 1998 The Fisher ies Society of the British Isles.