Different populations vary in appearance somewhat (see image of Salween specimen for example), and L. leptocheilus may turn out to represent a group of closely-related species rather than a single taxon. The population from the Cambodian Mekong has been considered to represent a distinct species, Labiobarbus lineatus, although that name is currently a synonym of L. leptocheilus following Kottelat (2013). It is widely used in the ornamental trade, however.

Following Roberts (1997) G. ariza can be diagnosed by the following combination of characters: body with variably intense thin stripes dustributed mostly above the lateral line; larger individuals sometimes with a broad midlateral stripe; 32-35 lateral scales; 7-8/1/5-6 transverse scale rows; 8-9 branched dorsal-fin rays 8-9; 22-24+ 11-12=34(4), 35 (3) vertebrae; live colour pattern variable, overall dull dirty white to greyish, silvery or yellow.

Known with certainty from the Irrawaddy River system in Manipur state, India, and Myanmar, and the Salween watershed in eastern Myanmar and northwestern Thailand. Records from the Red River basin in Vietnam appear questionable.

Type locality is ‘Burma: Myitkyina District: Mali Hka basin: Phungin Hka;’.

This species is extremely widespread and has been recorded from Pakistan, Nepal, most of India, Bangladesh, Myanmar and southern China.

Type locality is ‘Bengal and western provinces, India’.

Despite its unsuitability for the majority of home aquaria, this species is available in the aquarium trade on an irregular basis, and has also been marketed as ‘violet-gilled shark’, ‘red-gilled violet shark’ and ‘blushing violet shark’.

It appears likely that L. boga as currently recognised represents a complex of closely-related species.

This species can be identified by colour pattern comprising a brownish dorsal surface, yellowish flanks and abdomen, and a black to bluish lateral stripe extending from the eye to the caudal-fin base.

Endemic to the Salween river system in Yunnan province, southern China, eastern Myanmar, and northwestern Thailand.

Type locality is ‘Salween River midway between Mae Sam Laep and Paleh, Mae Hong Son province, Thailand.’

G. salweenica can be distinguished from other congeners inhabiting the Salween watershed by the following combinatuion of characters: body brownish; presence of a trilobed proboscis on the snout; snout blunt; a series of black spots at the base of the central dorsal-fin rays; presence of longitudinal stripes on the posterior portion of the body; a dark marking at the tip of the upper (and lower in some specimens) caudal-fin lobe; body depth 22.4-25.3 % SL.

G. rakhinica can be distinguished from other members of the genus by the following combination of characters: rostral furrow shallow and snout tip smoothly rounded; rostral lobe present, proboscis absent; scaled predorsal region, chest, and abdomen; two pairs of barbels; 28 lateral line scales; 16 circumpeduncular scale rows; colour pattern almost uniform greyish on body and caudal-fin; a dark spot immediately posterior to the upper extremity of the…

The Naung Pin Thar Chaung is located in a hilly area mostly comprising bamboo forest. In 1998 the water was clear, colourless and flowing at a moderate pace over a substrate of rocks and gravel. It was 1-2 metres wide and maximum depth was only 0.5 metres.

Due to the surrounding forest some stretches were shaded and others more open. Sympatric species included Garra spilota, Homalopteroides modestus, Mystus pulcher, and Xenentodon cancila, plus…