Restricted to remnant blackwater habits in heavily-disturbed areas of former peat swamp forest, the original vegetation having been cleared to make space for plantations of oil pal, pineapple and rubber. It’s now typically found among overhanging marginal vegetation of irrigation canals, with sympatric species including Belontia hasseltii, Betta bellica, B. imbellis, Sphaerichthys osphromenoides, Parosphromenus sp., and Trichopsis vittata. PH in its natural waters has been recorded over the range 3.9 – 4.2.

B. pinguis is included in the Betta akarensis group/complex of closely-related species within the genus, of which members share the following set of characters: possession of pre-orbital and post-orbital stripes (the post-orbital stripe is faint or interrupted in some species); chin bar present; caudal-fin lanceolate with highly extended median rays in mature males; caudal fin usually with transverse bars; greenish or bluish iridescent scales on body of males in some species; opercle without iridescent scales except in juveniles.

The easiest way to distinguish these is by examining the throat markings, which vary according to species, and in the case of B. hipposideros form a black horse-shoe shape. It can also be separated from other group members by the following suite of characters: dark blotch on throat joined to black lower lip; presence of transverse bars in dorsal and caudal fins; absence of dark margin in anal-fin; opercle usually with gold scales, without iridescrent green scales; ventral margin of opercle brown; 6.5-7 subdorsal scales (mode 6.5); 9-10 postdorsal scales (mode 9.5); 31-32 lateral scales (mode 32).

This species is included in the Betta waseri group/complex of closely-related species within the genus, an assemblage which also includes a handful of unidentified fishes such as B. sp. ‘Medas’ on an unofficial basis. Group members share the following combination of characters: base body colouration clay yellow; opercle scales iridescent gold in mature males of all species except …

Has been collected from a slowly-moving creek which ranged in depth from 20-50 cm. The water was clear and slightly-stained with tannins and the subtrate was covered by a layer of leaf litter. PH was 6.3, conductivity 82 µS/cm and water temperature 25.5°C. At another locality pH was 6.5, conductivity 69 µS/cm and water temperature 26.6 °C.

Presumed endemic to the geographically-isolated Maliau basin, a roughly circular plateau enclosed by hills in Sabah state, Malaysia, Borneo. The Maliau River is part of the much larger Kinabantangan watershed, Malaysia’s second longest river.

The type series was collected from heath forest alongside ‘Puntius‘ sealei and Hemibagrus cf. baramensis in acidic water with a pH of 4.2-4.8. Adult individuals were spaced around a metre apa…

This species is the only member of the B. edithae group within the genus, and separated from all other Betta spp. by the fact that the branchiostegal membrane and posterior portion of the opercle are opaque or translucent.

The original diagnosis by Vierke also states that it has relatively small eyes and short fins with a typical pattern of partial barring.

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…

Additonally, fin patterning in B. albimarginata, except the pectoral fins, consists of a broad white distal band, broad dark submarginal band with sharp outer margin and less sharp inner margin, and a plain red inner portion, while in B. channoides the dorsal fin is almost entirely red with only a thin white distal band and the dark submarginal band in the caudal fin does not extend into the uppermost portion of the fin. Base body colouration tends towards a brick-red shade in displaying male B. albimarginata, scarlet in B. channoides (pers. obv.).

This species differs from all other described members of the genus by the presence of dark blotches at the dorsal and ventral base of the pectoral fins. Three very similar-looking fishes have been assigned the codes A106, A107 and A108 under the DATZ system and are also known in the aquarium hobby as A. sp. ‘rotpunkt’ (this form has been in the hobby for decades with its precise origin unclear), A. sp. ‘rotpunkt Orteguazas’ (the paratype form of A. alacrina) and A. sp. ‘rotpunkt Guayas’, respectively. It remains to be seen whether they’re conspecific with A. alacrina or not since they exhibit some differences in colour pattern and morphology.