The Irrawaddy River crosses international borders throughout South-Eastern Asia, though several heads of different streams connected to the river are found in China. In the present study, two species never previously described were identified during taxonomic works on
Schizothorax
species distributed in the Irrawaddy drainage area in China, and were named
Schizothorax leukus
sp. nov. and
Schizothorax heteri
sp. nov.
Schizothorax leukus
can be distinguished from its congeners by a combination of the following characters: surface of lower lip covered with papilla, posterior edge of lower lip straight; low jaw developed, almost full the oral cavity, anterior edge of low jaw covered with horny sheath; breast and belly before pectoral-fin tip scaleless; barbels equal to eye diameter; last un-branched dorsal fin ray soft, lower third of the ray enlarged with posterior edge serrated; lateral line scales 94-105, scales between dorsal-fin origin to lateral line 26-34, scales between pelvic-fin origin to lateral line 21-27; outer side of the first gill arch with 16-20 gill rakers; body dark brown, without dark spots.
Schizothorax heteri can be distinguished from its congeners by a combination of the following characters: rostral fold equal to upper lip; lower lip developed, trilobed, the median lobe minute, its width equal to diameter of the rostral barbel base; postlabial groove continuous; low jaw without horny sheath; breast and belly before pectoral-fin tip scaleless; barbels equal to eye diameter; last un-branched dorsal fin ray strong, posterior edge serrated; dorsal-fin origin posterior to pelvic-fin origin; lateral line scales 89-104, scales between dorsal-fin origin to lateral line 24-33, scales between pelvic-fin origin to lateral line 19-29; body light brown, without any spots. Likewise, we discuss the validation of
S. rotundimaxillaris
and the questionable records of
S. molesworthi
,
S. griseus
and
S. paoshanensis
. In total, eight valid species of
Schizothorax were found and recorded from the Chinese Irrawaddy drainage area, with a key for identification is provided.
