Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Perciformes
(Perch-likes) > Osphronemidae
(Gouramies) > Macropodusinae
Etymology: Betta: Siamese local name of the fish "ikan bettah". More on author: Kottelat.
Environment / Climate / Range
Freshwater; benthopelagic. Tropical
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 3.5 cm SL male/unsexed; (Ref. 38481)
(total): 1 - 2;
soft rays: 19 - 21. This species is closely related to Betta picta from Java where it can be distinguished in the following characters: fewer dorsal fin rays (mode 8 vs. 9); fewer lateral scales (mode 27 vs. 28); dorsal fin origin above 11-12th lateral scale (vs. 12-14th); anal fin origin below modal 6th lateral scale (vs. 7th); fewer predorsal scales (mode 19 vs. 20); slightly greater anal-fin base length (46.5-50.3% SL vs. 42.6-48.4); anal and caudal fins with reddish distal band in live male (vs. bluish); iridescent greenish-blue opercle scales (vs. yellow-gold); in preserved specimens, male with distinct dorsal transverse bars (vs. faint); male with distinct dark anal distal margin wide (vs. narrow); male without elongated median caudal fin rays (vs. presence); female with distinct caudal transverse bars (vs. very faint or absent); dorsal head view narrow (vs. broad); thick preorbital black stripe (vs. narrow); and the distance between posterior part of anal fin to lower part of caudal narrow (vs. wide) (Ref. 56386).
Asia: central Sumatra, Indonesia.
Typically found among submerged bank vegetation, in near stagnant waters, with pH 4.7-6.8. Latin word falx means scythe, alluding to the continuous curved shape of the broad anal and caudal distal margins of a male in display. Caudal fin rounded.
Tan, H.H. and M. Kottelat, 1998. Redescription of Betta picta (Teleostei: Osphronemidae) and description of B. falx sp. n. from central Sumatra. Rev. Suisse Zool. 105(3):557-568.
IUCN Red List Status (Ref. 90363)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
CollaboratorsPicturesStamps, CoinsSoundsCiguateraSpeedSwim. typeGill areaOtolithsBrainsVision
Estimates of some properties based on empirical models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01120 (0.00513 - 0.02445), b=3.04 (2.87 - 3.21), based on all LWR estimates for this BS (Ref. 93245
Trophic Level (Ref. 69278
): 3.1 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .