The most essential item of décor is a soft, sandy substrate so that the fish can browse naturally (see ‘Diet’).

Coarser materials such as gravel or small pebbles can inhibit feeding, damage gill filaments and even be ingested with the potential of internal damage or blockages.

Additional furnishings ar…

It’s care requirements, disposition, and especially conservation status dictate that it should be maintained alone or alongside a group of small, peaceful cyprinids such as Boraras or Sundadanio spp.

Likewise, different Parosphromenus spp. should not be kept together since the females of many are very difficult to tell apart and some are undoubtedly capable of hybridising.

Type locality is given only as ‘Sarawak state, Borneo, East Malaysia’, with the material deriving from Sibu Division in western Sarawak.

It’s since been recorded at other localities within Sarawak, to which it appears endemic, but it remains unclear whether all represent a single species or not with those from the area around Lundu in northwestern Kuching Division in par…

Type locality is ‘Kota Tinggi, Mawai-Desaru road, Johor, Peninsula Malaysia’ and this species is endemic to a small portion of eastern Johor state, Peninsular Malaysia around the towns of Kota Tinggi, Mawai and Desaru.

A great deal of its original habitat has been lost via deforestation and other human alterations and it’s considered in grave danger of extinction.

This species is relatively uncommon in the aquarium hobby but is available on occasion, sometimes mixed in among shipments of the congener C. salivator.

These two can be told apart by the fact that C. salivator possesses a series of distinct dark bars on the head and body in both sexes, a colour pattern unique within the genus.

It is also similar t…

This species is not available on a commercial basis but was collected and introduced to the aquarium hobby by Hans Georg-Evers in 2010.

It’s similar in appearance to a number of congeners including C. diphyes, C. erhardti, C. garbei, C. paleatus and C. steindachneri but can be told apart from most of them by possession of two large, indistinct, dark blotches in the middle of each flank.

P. arnoulti has been in the aquarium hobby for many years but was identified as the congener P. omalonotus prior to its description.

It appears in the majority of older aquarium literature under that name and as a result a degree of hybridisation has undoubtedly occurred.

This species appears endemic to and abundant within the upper Suriname River system, Suriname.

Type locality is given as ‘little tributaries of Gran Rio between Ligolio and Awaradam Falls’, this corresponding to a section of the Suriname River, which is known as ‘Gran Río’ in parts of its upper basin, upstream of Brokopondo reservoir and not…

C. aurofrenatus is currently understood to occur throughout much of the Río Paraguay-Paraná system in Paraguay, and has also been recorded in Argentina and Bolivia.

It was described from Paraguay with type locality given as ‘Aguada near Arroyo Trementina’. The latter is stated to be a tributary of the ‘Rio Aquido Canigi’.

There appears to be some discrepancy between Smith’s original description and Kottelat (1990) in that Smith states the fish is a member of a group of species lacking an ocellus at the upper caudal-fin base, whereas Kottelat mentions the presence of ‘a black spot at upper extremity of caudal-fin base, surrounded by a whitish area’.