Known only from a handful of localities within the Xi River (Xi Jiang) drainage in Guangxi Zhuang Autonomous Region, southern China plus the Tuoniang river system in Funing County, southeastern Yunnan province.

Type locality is ‘West River, Longzhow Xian, Guangxi Province, China’.

This fish remains in need of identification, and we’ve chosen to list unidentified members of the genus using an ‘ER’ numbering system in the absence of definitive information.

It’s quite easy to distinguish from congeners since it’s the only species known to possess a colour pattern comprising a dark base colour and series of thin, paler vertical bars on the body and similarly-coloured spots on the head.

This species is variable in terms of colour. Large adults may be bright green, orange or barred but are apparently capable of changing from barred to plain in just a few seconds.

These different forms have been recorded in the same natural habitats, and some individuals also possess prominent nuptial tubercules covering much of the body.

The type locality was a fast-flowing, shallow (50 – 80 cm deep) river between 5-10 metres in width with a substrate of gravel and large rocks. PH was measured at 7.7 and the habitat was unshaded with on…

This species appeared in the trade during 2010 and its identity has been confirmed to us by Thai exporter and aquarist Kamphol Udomritthiruj who collects it from the Se Kong system for the aquarium hobby. To date only subadult specimens have reached the western market.

This fish has thus far only been imported among shipments of S. sp. ‘SEW02’ and S. sp. ‘SEW03’. It doesn’t appear to correspond to any known member of the genus and may be undescribed.

Prior to the mid-1990s S. lineolata was the only species in the genus but an upturn in surveys of fresh water fauna in Vietnam and Laos has resulted in the discovery of various new taxa, several of which remain undescribed.

This fish first became available in early 2009 and was initially identified as S. breviventralis (Freyhof and Serov, 2000).

However it cannot be that species because there is no discernible gap between pelvic and anal fins, which also discounts the possibility of it being S. elongata (Roberts, 1998). It therefore remains unidentified and is often imported in mixed batches with S. sp. ‘SEW02’, which it also resembles closely.

This is one of the more readily-available members of the genus and popularly referred to as S. sp. 'spotted' or S. sp. 'special'. It's superficially similar in appearance to S. albisuera but in that species body patterning consists of a network of irregular dark lines forming a complicated series of reticulations vs. many small, light spots on a dark background in S. sp. 'SEW01'.

It's been suggested that these two may represent the same species but this…

This species first became available in early 2009 and was initially identified as S. breviventralis (Freyhof and Serov, 2000) because there is a clear space between the pelvic and anal fins and body patterning is vaguely similar to that species, and also appears quite similar to S. elongata (Roberts, 1998) and S. sp. ‘SEW03’.

It does not fully match the original descriptions of either, however, and therefore remains in need of identification.

S. lineolata was first recorded by Diard over 150 years prior to its 'rediscovery' in the early-1990s. It became available to the aquarium trade in the mid-2000s and swiftly established itself as one of the more popular balitorids in the hobby due to its attractive body markings and ease of breeding. It's also sold under the names 'reticulated hillstream loach', 'Vietnamese hillstream loach' and 'gold ring butterfly sucker'.

It's difficult to…