The massive decline in wild populations, hypothesised to be in excess of 90% since the mid-1980s, is thought to have been caused by a variety of factors, including habitat alteration due to construction of dams and other infrastructure, removal of riparian vegetation, and urban pollution, plus over fishing for both human consumption and the aquarium trade.

Lobocheilos species are specialised grazers of periphyton, benthic algae, and other organisms which grow attached to rocks and other solid surfaces, and they typically leave visible scrape marks in places where they have been feeding.

They are by no means herbivorous and should be offered meaty foods such as live or frozen chironomid larvae (bloodworm), Tubifex, Artemia, chopped prawn, etc., along with good quality, sinking dried products, at lea…

The majority of Lobocheilos species are endemic to the Greater Sunda Islands of Borneo, Sumatra, and Java, and are uncommon in the aquarium trade, but the widespread Indochinese taxa L. melanotaenia and L. rhabdoura are available on a sporadic basis.

L. melanotaenia can be distinguished from L. rhabdoura by the following comb…

Considered synonymous with the congener L. laubuca for a number of years, thus reports of that species from anywhere in Indochina actually refer to the current concept of L. siamensis.

Given the distribution of L. siamensis, it seems likely that many of the fish entering the aquarium trade are also this species and not L. laubuca. The two species can be distinguished by…

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.

This species can be distinguished by the following characters: juveniles with brown body and dark marking at base of caudal-fin; 37-42 + 3-4 lateral line scales; 11½ branched dorsal-fin rays; 7½ scale rows between lateral line and dorsal-fin origin; 20-25 predorsal scales; dorsal-fin relatively small with anterior branched rays shorter than head in juveniles, slightly longer than head in adults.

L. chrysophekadion is also known as ‘black sharkminnow’. It continues to be available in the ornamental trade despite its patent unsuitability for the home aquarium, and an albino form has been selectively bred for the purpose.

It can be distinguished from other members of the genus by the following combination…

It is very similar to H. wetmorei but can be told apart by possessing yellow (vs. orange to red in H. wetmorei) pectoral, pelvic, and anal fins. It thus appears likely that yellow-finned fish marketed as H. wetmorei or ‘lemon fin barb’ in the ornamental trade are actually H. vernayi, with both species available on a regular basis.

Known from the middle and lower Mekong basins in Laos, Thailand, Cambodia, and Vietnam, plus the Dong Nai drainage in central Vietnam.

Type locality is ‘Rapids of Dang-nai, Bien Hoa Province, Thailand’, which corresponds to what is now the city of Biên Hòa in Đồng Nai province, southern Vietnam.

It can be distinguished from congeners by possessing one or two pairs of barbels, a black blotch at the base of the caudal-fin, and rows of dark spots along the lateral scale rows.

Members of Cyclocheilichthys are characterised by possessing a serrated dorsal fin spine, 9 branched pelvic fin rays, a conical snout, small, subterminal…