Three new species of Gastromyzon (Teleostei: Balitoridae) from the Temburong River Basin, Brunei Darussalam, Borneo

Three new species of Gastromyzon from Brunei Darussalam, on the island of Borneo, are described from recent collections and from older museum specimens. Gastromyzon cranbrooki, new species, is superficially similar to G. borneensis, but differs in having a distinct secondary rostrum; body brown with 9-10 grey bars, head dorsum dark brown with thin grey reticulate pattern; and 56-60 scales on lateral line. Gastromyzon aeroides, new species, is similar to G. punctulatus, but differs in having the body uniform brown, dorsum uniform brown; head dorsum with very fine cream reticulate pattern ( similar to a cream head with brown spots and blotches); dorsal, caudal and anal fins blue in life; and 47-65 scales in lateral line. Gastromyzon venustus, new species, is similar to G. pariclavis, but differs in having both the body and head dorsum plain brown; dorsal, caudal and anal fins red in life; and 58-63 scales in lateral line.