Ichthyologists Heok Hui Tan and Maurice Kottelat have described six new species of fish from central Sumatra.
The descriptions are published as part of a checklist of fishes in the Batang Hari River drainage in Sumatra and appear in a recent issue of the journal Ichthyological Exploration of Freshwaters.
The six new species described are three cyprinids (Crossocheilus obscurus, Osteochilus kerinciensis, Pectenocypris micromysticetus), one nemacheilid loach (Nemacheilus papillos) and two cobitid loaches (Pangio atactos, P. bitaimac). The study also records 297 species of fishes from the Batang Hari drainage.
Crossocheilus obscurus
This species is distinguished from congeners by a large body size (at least 14 cm standard length), only one pair of rostral barbels and no maxillary barbels present, midlateral stripe without sharply contrasting edges, slightly curving downwards, obscured in largest individuals and running to the caudal fin, absence of a black mark between anus and anal fin and a wide mouth (30"36 % head length).
Osteochilus kerinciensis
Osteochilus kerinciensis differs from congeners in having a black midlateral stripe running along the entire length of the body and extending onto the caudal fin, three tubercles on the tip of the snout, red fins, transverse groove across the snout, and a subinferior mouth.
Pectenocypris micromysticetus
This species is distinguished from congeners by 45"70+120"170 gill rakers on the first gill arch, an elongate dark blotch at the base of the caudal fin, and the midlateral stripe on the body very faint or absent.
Nemacheilus papillos
Nemacheilus papillos is distinguished from congeners in having strongly papillated lips, the anterior nostril at the tip of a short tube and a colour pattern consisting of 10"11 dark vertical bars that are much wider at level of lateral line and those behind the dorsal-fin origin fused at level of lateral line.
Pangio atactos
This species is distinguished from congeners by its unique colour pattern of 7"9 irregular triangular saddles along the back alternating with a row of spots or blotches on the middle or lower half of the body.
Pangio bitaimac
Pangio bitaimac is distinguished from congeners in having a very long and slender body, the origin of the anal fin behind the base of the dorsal fin, 7+7 branched caudal-fin rays, cheek unscaled, and the tube of the anterior nostril developed into a barbel.
For more information, see the paper: Tan, HH and M Kottelat (2009) The fishes of the Batang Hari drainage, Sumatra, with description of six new species. Ichthyological Exploration of Freshwaters 20, pp. 13"69.