Known from the lower Mekong River basin in Laos, Thailand, Cambodia, and Vietnam, plus tributaries of the Chao Phraya watershed in central Thailand, and drainages between the Chao Phraya and Mekong in eastern Thailand.

Type locality is ‘Nam-Mun at Korat, 135 miles northeast of Bangkok, Thailand’.

In 1996 the species was known from five localities in Hong Kong, but at least one of these has been destroyed and it is now known only from Tai Po and Sai Kung districts. Additional populations have subsequently been discovered in Guangdong and Fujian provinces on the southern Chinese mainland.

Type locality is ‘China: Hong Kong: Tai Po: Sha Lo Tung’.

This species is frequently mistaken for the similar-looking congener M. spechti Schreitmüller 1936, which is easily-identified by the absence of reddish pigmentation in the dorsal, anal, and caudal fins. There has been some debate as to whether these two represent the same taxon, however, with Winstanley and Clements (2008) proposing that M. erythropterus be considered a synonym of M. spechti because they were unable to separate the two species by morphological characters, and specimens with red pigmentation on the unpaired fins were coll…

Bintan has been developed for tourism over the last decades and is heavily-promoted by Indonesia, with luxury beach resorts and golf courses increasing in number. Further deforestation has occurred in order to establish large rubber plantations in the interior of the island. B. miniopinna is now restricted to a few remaining pockets of primary peat swamp forest and has been listed as ‘Critically Endangered’ on the IUCN Red List of Threatened Species since 1996.

This species is most easily told apart from its only congener P. dayi by lacking (vs. possessing) two dark, irregular lateral stripes on the head and body, and a shorter caudal-fin in males.

The results of phylogenetic analyses by Rüber et al. (2006) suggest that Pseudosphromenus is most closely-related to Malpulutta in an evolutionary sense.

This species was considered a colour form of the closely-related B. imbellis and commonly-referred to as ‘black imbellis’ prior to description due to its blackish opercle and body.

It’s also previously been confused with B. splendens due to the colour of the vertical opercular bars which tend to be reddish (but may also be pale red, greenish-silvery, plain silvery or without colour in some populations), but DNA analysis has demonstrated it…

This species is available in the aquarium hobby but is not traded in large numbers and may have been inadvertently hybridised with the similar-looking congener B. rubra prior to its description since they’re typically exported mixed together.

It’s included in the B. rubra group of closely-related species within the genus, an assemblage erected by Schindler and van der Voort (2012) who…

This fish has been widely available in the aquarium trade in recent years and is sometime referred to by the invented name P. ‘sintangensis’.

It displays a close resemblance to P. bintan and another unidentified fish known to aquarists as P. sp. ‘blue line’ although the inner bluish bands in the dorsal, anal and caudal fins are perhaps a little narrower in P. sp. ‘Sentang’ than the other two.

This species has been known in the aquarium hobby since the mid-twentieth century but has almost always been identified as the congener P. deissneri and appears as such in the majority of aquarium literature.

It can be told apart from congeners by the colour pattern in adult males (see ‘Sexual Dimorphism’) plus possession of 11-12 spinous dorsal-fin rays, 13-14 spinous anal-fin rays and 6-8 segmented anal-fin rays.

This species has occasionally been traded on a commercial basis and was known as P. sp. ‘Manis Mata’ prior to description, with the latter apparently referring to a location some 100 km away from the type locality where the fish do not occur.

It’s said to be slightly easier to maintain than the majority of congeners and is therefore a recommended choice for those ne…