This species is traded under several names of which others include ‘Samurai gourami’ and ‘Samurai Zebra Chocolate Gourami’. Though the former of these is arguably the most common, these names are potentially misleading since the fish is neither especially combative nor from Japan.

Its unique colour pattern makes it difficult to confuse with any of the three other members of the genus even in the abse…

This species is traded under several names of which others include 'sharp-nosed gourami', 'moonlight chocolate gourami', 'black-lined chocolate gourami' and 'black-tailed chocolate gourami', though it's far from common in the hobby. Its unique colour pattern makes it difficult to confuse with any of the three other members of the genus even in the absence of meristic data.

This species is sometimes traded under the names 'mini chocolate gourami', 'Burmese chocolate gourami' or mislabelled as the congener P. ocellatus, these two currently comprising the only known members of the genus.

P. lineatus can be told apart from P. ocellatus via the following combination of characters: smaller body size (maximum standard length 18.7 mm vs. 32.0 mm); absence of ocellus-type marking in middle of each flank (vs. presence); presence of dark, stripe (vs. abs…

Utilises a strategy which has become known as ‘pelvic brooding’. Spawning tends to occur in the early morning, with dominant males darkening in colouration and defending their space by driving away potential competitors, while approaching ripe females in a rigid ‘head-down’ position.

The eggs normally number 8-12 and are expelled as a single mass while being fertilised simultaneously, after which they continue to hang from th…

Commonly known as ‘Japanese rice fish’ or simply ‘rice fish’, O. latipes is well-known to science having been widely used as a model organism in genomic and experimental biology for well over a century and was the first vertebrate animal to mate in space during the mid-1990s.

It’s also been a popular aquarium fish for many years, though is less widely-available than it once was, with the ornamental ‘gold’ vari…

An exclusive inhabitant of fresh, normally standing, waters including shallow pools, ditches, rice paddies and clear water swamps. The type locality is a small ditch measuring just 3 – 6 metres in width and 0.5 – 2 metres deep. The water was clear and the substrate composed of sand, detritus and mud with growths of the macrophytes Nymphaea lotus, Jussiaea repens and Hydrilla verticillata.

Best maintained in a heavily planted set-up, ideally with a dark substrate, patches of dense vegetation, and some open areas. Other décor can consist of twisted roots and pieces of bogwood, while surface vegetation is also appreciated by the fish. When maintained under such conditions they’re more likely to display their best colours, and planted aquaria also offer fry a more favourable chance of survival alongside the adults.

It can be further distinguished from congeners by the following combination of characters: small adult size; bright orange-red marginal bands on caudal-fin lobes in males; caudal-fin rounded and elongate; 5-7 dorsal-fin rays; relatively few (13-18) anal-fin rays without bony contact organs, the last ray branched; 6-8 pectoral-fin rays.

Members of the family Adrianichthyidae are…

This species continues to be mislabelled as O. melastigma, a name currently considered invalid by the majority of recent workers, or O. javanicus, a valid but distinct taxon. Roberts (1998) demonstrated that MClelland’s description of Aplocheilus melastigmus, later renamed O. melastigma, does not correspond with any known Oryzias species from the Indian subcontinent or Myanmar since it’s said to have a dark spot in the dorsal-fin and an excessively slim body, among other anomalies.

This species is exceptionally rare in the aquarium trade and can be distinguished from congeners by the following combination of characters: snout narrow with head appearing triangular as a resul…