Three new species of Gastromyzon (Teleostei: Balitoridae) from southern Sarawak

Abstract

Three new species of the genus Gastromyzon are described from southern Sarawak. Gastromyzon scitulus, new species, is similar to G. ctenocephalus but differs in having a black body, with numerous evenly spaced smaller light brown spots, head dorsum black, with numerous cream spots, pectoral and pelvic fins with cream spots; caudal fin with iridescent blue streaks when live; and 57– 58 scales in lateral line. Gastromyzon crenastus, new species, is the smallest known Gastromyzon, largest recorded specimen measuring only 29.7 mm SL. It is similar to G. ridens, but differs in having a black body, dorsum with 6–8 thin cream bars or spots, head black with cream spots and blotches; a truncate snout when viewed dorsally; and 60–65 scales in lateral line. Gastromyzon farragus, new species, is similar to G. ocellatus but differs in having a dark brown body, dorsum with 9–10 thin cream bars, side with spots and blotches, head dorsum dark brown with fine cream spots; caudal fin reddish in life; and 52–55 scales in lateral line. Data on these species are presented, together with a short discussion on their ecology.