Also known as the golden trahira, H. unitaeniatus is the only one of the three recognised species currently in the genus to appear in the trade with any regularity. It's really a fish suitable only for the specialist, and as with any predatory species, care must be taken when performing tank maintenance.

It's a representative of an ancient group of fishes, and possesses a modified, highly vascularised swim bladder that acts as an accessory breathing organ, allowing the fish to survi…

A species for the specialist, E. erythrinus is also known as the rainbow wolf fish or red hi-fin wolf fish. It is quite variable in colour and pattern depending on collection locality. There is a variant from Peru that has a bright orange belly. Recent studies have highlighted genetic differences in these different populations, suggesting that E. erythrinus is actually a species complex, rather than a single species. There is currently one other recognised species in the genus, E. kessleri, but …

This species is now considered a member of the Hara genus by many experts, but as things stand it is still officially included in Erethistes. It is, in all likelihood, a Hara, as Erethistes is characterised by divergent denticles on the pectoral fins, whereas Hara possess outwardly pointing denticles. E. maesotensis has these outwardly pointing denticles.

It's quite rare in the trade, but makes an interesting addition to an Asian stream community tank if you can get hold of some….

Not often seen for sale, but if you can find it, it makes a peaceful addition to the brackish or hardwater community of medium-sized fish. It was previously considered a member of the now defunct genus Batanga. The fish in our picture is a young specimen. Adults develop a pleasing pattern of reds and blues and are most attractive….

T. hengeli is sometimes seen for sale with the trade name of ‘glowlight rasbora’ due to the distinctive orange patterning on the posterior part of the body but we’ve refrained from using that name here because it’s also commonly applied to Trigonopoma pauciperforatum.

It can be confused with the similar-looking T. heteromorpha and T. espei although on close inspection they’re actually quite easy to tell…

This species is very peaceful indeed making it an ideal resident of the well-maintained community tank. As it places no extreme demands in terms of water chemistry it can be combined with many of the most popular fish in the hobby including other small cyprinids as well as tetras, livebearers, dwarf cichlids, catfishes, and loaches. As always when selecting a compatible community of fish thorough research is essential and its small adult size must be a consideration, however.

This species was initially described as Rasbora axelrodi and is referred to as such in older literature, but in 1999 was moved into the new genus Sundadanio where it remains the monotype. Its wider placement within the family Cyprinidae is still not fully resolved. Following Rüber et al. (2007) it is most closely-related to the miniature species of the genus Paedocypris, the two genera characteristically lacking bones in the roof of the skull as well as exhibiting genetic similarities. Howe…

S. resplendens is traded under several names including ‘Asian rummynose’, ‘rummynose rasbora’ and ‘naked microrasbora’. It can be immediately distinguished from all other Asian cyprinids by the distinctive colour pattern.

The genus Sawbwa is currently monotypic and endemic to the isolated lake basin of Inlé in Shan State, eastern Myanmar.

These are still regarded as valid by some authorities although it’s widely accepted that they represent variants of R. vaterifloris due to a lack of type material hindering conclusive study. Rasboroides nigromarginata (Meinken, 1956) has also been used to refer to a reddish form in which males differ from other populations in possessing dark fin margins, but the name is currently considered synonymous with R. vaterifloris by most sources despite the fish being rediscovered in 2010.

An ideal resident of the larger, well-furnished community set-up though it might upset slow-moving or timid companions simply by its size.

There are plenty of suitable tankmates including many cyprinids, loaches, cichlids, catfish and characins, but as always when selecting a compatible community of fish proper research is essential. A community based around one of its native countries or river basins…