Mahakam

This is the most commonly-encountered representative of the genus in the aquatic trade though is by no means common. As in other members of the genus body colouration is highly variable, even among individuals collected from a single locality, although a few useful regularities have been observed which can be used to distinguish certain species. This is thought related to the fact that Acrochordonichthys spp. periodically shed their skins and appear paler post-moulting. A. rugosus lends its ...

This is one of two species traded under the vernacular name 'tinfoil barb', the other being the less well-known congener B. altus. Despite this it appears that B. altus is just as widely available as B. schwanefeldii and in many cases is seen on sale more regularly. Unfortunately both are usually offered at a small size (usually around 50 - 75 mm) with little to no information regarding the eventual size of the fish.

Likely to prey on insects and other small invertebrates/zooplankton in nature. Captive fish will normally accept dried products once they're recognised as edible, but should be offered plenty of small live or frozen foods such as Daphnia, Artemia or bloodworm regularly to ensure development of optimal colour and condition. Small insects such as crickets or Drosophila fru...

B. channoides and B. albimarginata together comprise the Betta albimarginata group/complex of closely-related species within the genus, these differing from all other members of the genus in colour pattern and by possession of 9-12 anal-fin spines (vs. 0-4). They look very similar to one another but differ in the following characters: anal fin spines 9-11 in B. albimarginata vs. 12 in B. channoides; anal fin rays 21-23 vs. 23-25; lateral scale rows 26-27 vs. 27.5-28; trans...

This species is included in the Betta unimaculata complex of closely-related species within the genus, of which members share the following set of characters: body long and slender with depth at dorsal fin origin 18-25 % SL; head large and blunt with width 19-24 % SL; long maxilla and lower lip with distance from tip of lower jaw to posterior end of maxilla 27-54 % HL; caudal-fin rounded in shape, occasionally with elongated median rays; pelvic-fin short and filamentous; dorsal and anal fins relatively pointed.

Prefers a dimly-lit aquarium with plenty of cover in the form of live plants, driftwood branches, terracotta pipes, plant pots, etc., arranged to form a network of nooks, crannies, and shaded spots. Surface vegetation such as Ceratopteris spp. is also appreciated and makes the fish less inclined to conceal themselves.

While separating some of the fish that may be found on sale as 'C. siamensis' is a tricky task, C. nigriloba is quite simple to identify. The dark lateral body stripe uniquely breaks up into a series of blotches when the fish are sparring, stressed or sleeping and the lower caudal fin lobe contains dark pigmentation suffused with red. The latter feature has given rise to the trade name of 'penguin flying fox'.

D. foerschi is sometimes traded as 'boomerang barb' or 'Foersch's fire barb' and is included in a group of closely-related, similar-looking fishes which were moved into the new genus Desmopuntius by Kottelat (2013). It can be told apart from other vertically-striped congeners by possession of additional dark blotches between the second, third and fourth vertical bars and a further marking at the posterior base o...

D. johorensis can be distinguished by the following combination of characters: 5-6 dark, lateral stripes on body in specimens larger than 40 mm; stripes immediately above and below the central stripe (stripes '+1' and '-1', respectively) located on scale rows +2 and -2, not touching dorsal and ventral midlines (except in some small specimens from Peninsular Malaysia); stripes broad, typically between 0.5-1 scale rows deep...

The pinkish-white form of this species is among the most widely-traded aquarium fishes in the world but does not occur naturally and is in fact a leucistic variant bred specifically for ornamental purposes. The 'short-bodied' or 'balloon' variety also continues to be fashionable but under no circumstances do we recommend the purchase of these intentionally disfigured animals which tend to have much shorter life spans than the naturally-shaped fish. There also exists a less-po...

This species appears is rare in the aquarium hobby with the majority of images both online and in the published literature instead depicting H. confuzona or H. parclitella. All three are members of the H. ocellata 'group' within the genus which currently contains H. ocellata, H. bilineata, H. confuzona, H. orthogoniata, H. ogilviei and H. parclitella. Following Tan and Ng (2005) these share possession of...

Tan (2009) redescribed H. stephensoni and it possesses the following unique character set: sub-inferior mouth with thin barbels; five principle, 12-13 secondary pectoral fin rays (usually 12); scaleless belly; pattern of keeled scales on anterior, dorsal portion of body consisting of a single central keel in the posterior third of each scale; 43-50 lateral line...

Different populations vary in appearance somewhat (see image of Salween specimen for example), and L. leptocheilus may turn out to represent a group of closely-related species rather than a single taxon. The population from the Cambodian Mekong has been considered to represent a distinct species, Labiobarbus lineatus, although that name is currently a synonym of L. leptocheilus following Kottelat (2013). It is widely used in the ornamental trade, however.

It can be distinguished from congeners by the following combination of characters: 61-68 scales in the lateral series; a small, well-defined, sometimes ocellated black spot on the shoulder and another in the centre of the caudal peduncle; body without longitudinal stripes formed by spots on scales; caudal fin uniformly dusky or colourless, lobes without stripes or black margins.

Patterning is highly variable depending both within and between populations and the species may comprise an assemblage containing a number of taxa (Kottelat and Lim, 1993; Tan and Kottelat, 2009). For example, those from Singapore and Johor possessing intricate mottling on the dorsal surface while individuals from Terengganu have a series of saddle-like markings either alternating or connecting with the midlateral markings.

This species occasionally appears in the aquarium hobby, but the trade is largely reliant on commercially-produced 'tiger barbs' of questionable origin. It was considered a synonym of P. anchisporus for a number of decades following Alfred (1963), but revalidated by Kottelat and Tan (2011).

It is thought to have been extirpated from the Chao Phraya and Mae Klong rivers, Lake Songkhla, and the entire island of Java due to a variety of anthropogenic factors, and the Mekong populations have also been drastically reduced. In particular, it is sensitive to pollution and gillnetting, and is heavily overfished.

Substrates are generally composed of gravel, rocks, boulders or bedrock carpeted with a rich biofilm formed by algae and other micro-organisms. At a habitat in the Mendawai river basin in central Kalimantan, H. borneensis was collected from a foothill stream running swiftly over a rock and gravel substrate with clear water of pH 6.4.

Known from the Pahang River system in southern Peninsular Malaysia, and the Greater Sunda Islands of Sumatra and Borneo. On the latter records exist from the Kapuas, Barito, and Mahakam watersheds in Kalimantan, the Indonesian portion of the island Type locality is 'Pangabuang, Lampong Province, Sumatra, Indonesia'.

The five species which currently comprise Luciosoma can be distinguished by elements of colour pattern. Popta described the colour pattern of L. pellegrinii as follows: body colour olive dorsally, with dark-edged scales, yellow ventrally; a lateral series of dark spots on the flank forming a midlateral band which extends onto the opercle but not the head; 4-8 blackish-brown, distinctly-separate spots on the lateral line; fins yellow; dorsal and anal fins with a blackish-brown band; anterior half of some pectoral-fin rays blackish-brown...

This species is poorly known in general and is not present in the ornamental trade, although its name is widely misapplied to other Luciosoma species. Its congeners are mostly marketed as 'apollo shark', 'shark minnow', or similar, and often labelled with incorrect scientific names. Identification of the fish pictured here is based on Bleeker (1855, 1860) and Roberts (1989), plus drawings by Bleeker, thus...