Populations from the upper Pearl River (Nanpan Jiang basin) differ in several morphological characters from those inhabiting Guangdong, Guangxi, and Guizhou Provinces, and Hainan Island. Those from Vietnam also seem to be different (Gan et al., 2009), the implication being that there may be several species currently included under the name M. lineata.

Although it is included in the genus Metzia this grouping remains somewhat unresolved in terms of taxonomy and it may contain more than a single genetic lineage. For example, members share a number of characters with the genera Ischikauia Jordan and Snyder 1900, Hemiculterella Warpachowski 1887, and several species of Anabarilius Cockerell 1923, including a bipartite gas bladder, a non-spinous dorsal-fin ray, and a sharp ventral keel between the pelvic-fin insertion and anus.

Among other Garra species from Southeast Asia and China, G. orientalis is most similar to G. salweenica and G. fuliginosa in that all three possess a roughly triangular, trilobed proboscis on the snout, the anterior margin of which is densely tuberculated, and the inferior margin not in contact with the depressed rostral surface, i.e., the proboscis projects forwards.

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…

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 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 to avoid confusion we list all together here.

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…

One of the most ubiquitous species in the hobby and several ornamental strains are available including ‘long-finned’, ‘golden’, ‘albino’, and ‘super red’, for which care is identical to that of the ‘standard’ fish.

Unfortunately the degree of inbreeding amongst farm-bred stock has resulted in a situation whereby many of the fish available today are genetically weak and prone to disease or develop physical deformities.

M. ocellatus can be distinguished from congeners by the following combination of characters: caudal-fin rounded; eye stripe not connecting spot on posterior projection of opercle with eye; dorsal-fin rays filamentous posterior to a vertical through the posterior anal-fin rays in adults; 16-19 spinous dorsal-fin rays; 6-13 rakers on ceratobranchial of first gill arch; posterior tip or margin of body scales not darker than scales.