Xi

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 species is one of several traded variously as 'butterfly loach', 'butterfly plec', 'Hong Kong plec(o)', 'Chinese hillstream loach' or simply 'hill stream loach'. In many countries it's the most common balitorid in the shops but is also often found in mixed shipments containing members of other genera. Like all balitorids it's an obligate bottom-dweller with specialised morphology adapted to life in fast-flowing water. The paire...

No bubble nest is built and several thousand eggs simply float at the surface with both male and female remaining to defend the eggs and fry. The eggs hatch after 24-36 hours depending on temperature and the fry are free swimming in a further 24 hours. At this point they resemble 6-7 mm long black tadpoles. It is important to constantly feed...

E. sinensis was initially included in the genus Protomyzon where it remained until 2004 when Kottelat found sufficient geographical and morphological differences between members of the group inhabiting the island of Borneo and those from mainland East/South East Asia to warrant their separation. The genus Erromyzon was erected to accommodate the mainland fishes and there are currently three...

It's told apart from congeners by a combination of characters as follows: large scales present on body and sides of head; caudal fin deeply forked with subequal lobes; 10-13 dark, vertical bars on the body; a dark, ocellated spot in the centre of the caudal-fin base; two bars on top of head, dorsal-fin with two rows of greyish spots; caudal-fin lobes with 3-4 dark bands on each; anal-fin with one indistinct band and another, more distinct, submarginal band; ventral fins with two indistinct bands.

This species appears to exist in a number of different forms which exhibit differences in colour pattern, morphology, or both, and it's currently unclear whether all of them are truly conspecific or not although those in the aquarium trade all appear similar to one another. We've been unable to obtain a copy of the original description so it's not currently possible to provide a detailed diagnosis either, with most recent studi...

This species is also sold under the vernacular names 'golden Chinese loach' and '12-banded Chinese loach'. Along with S. robusta it's the most commonly-traded member of the genus, and the two are often imported in mixed batches, presumably because they occur and are thus collected together in nature. Like most congeners it has a highly flexible, sinuous body which makes it very interesting to observe. S. pulchra can be differentiated from...

This species is also sold under the vernacular names 'golden Chinese loach' and '12-banded Chinese loach'. Along with S. pulchra it's the most commonly-traded member of the genus, and the two are often imported in mixed batches, presumably because they occur and are thus collected together in nature.

This species is probably the most common member of the genus in the aquarium trade but still not often exported in numbers. Instead it's more often found in mixed shipments of other wild-collected fishes from southern China, particularly Beaufortia or Pseudogastromyzon spp. It may appear superficially simi...

Despite being a wholly unsuitable aquarium subject, C. idella is often traded as such, with an albino form having been developed specifically for the ornamental market. Individuals which have outgrown their aquarium or pond should never be released into natural waters, either, since this species has proven capable of causing serious environmental damage under a wide range of climatic conditions.

Members of the genus are characterised by possessing a particular number of dark vertical bar on each flank, and A. parallens belongs to a group of species with five or six such bars, each of which is two scales in width. Congeners sharing this pattern include A. fasciatus, A. hemispinus (in juveniles only), A. jishouensis, A. kreyenbergii, A. paradoxus, A. spinifer, A. wenchowensis, and A. wuyiensis.