Scleropages formosus
No common name
Collection Details
Specimens
Photos
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Records
Taxonomic Hierarchy
Actinopterygii (Ray-finned Fishes)
Osteoglossiformes
Osteoglossidae (Arowanas)
Scleropages
Scleropages formosus
Description
This species account was compiled from
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Characters
Body shape: elongated. With 1 pair of barbels; scales large.
Distribution
Asia: Southern Myanmar to Malay Peninsula and Indonesia, eastern Thailand to Cardamon Range.
Habitat Associations
Freshwater. benthopelagic. Found in: streams.
Biology
Occurs in tannin stained blackwater streams (Ref. 12693). Found in forest covered streams including peat adjacent areas. Take around three months for free swimming fries (Ref. 57235). Young individuals feed on insects at the water surface, adults take fishes (Ref. 12693, 57235) and smaller vertebrates (Ref. 56749). A mouth brooder, young about 6 cm at birth (Ref. 7050, 57235). Valued as an aquarium fish, its flesh commands a moderate price.
Max length: 90.0 cm TL.
Reproductive mode: dioecism; fertilization: external; mating system: monogamy; bearers (external brooders). From an observation of a breeding pair in a concrete tank, courtship lasts from several weeks to months. During this stage, the breeding pair swims near the water surface usually at night. "The male chases the female around the perimeter of the tank. Sometimes, the pair circle each other nose-to-tail. About one to two weeks before spawning takes place, the fish swim side by side with their bodies touching. Eventually, the female releases a cluster of orange-red eggs. The male fertilises the eggs and then scoops them into its mouth where it incubates them. After hatching which occurs in about a week, the young larvae continue to live in the male's mouth for 7-8 weeks more until the yolk sac is totally absorbed" (Ref. 57886).
IUCN Red List Status: Endangered (EN), assessed 2019-06-03. Resilience: Low (tm = 3-4; Fec = 50 (in concrete tanks)).
Commercial or Environmental Importance
Fisheries: commercial; aquarium: highly commercial.
References
Axelrod, H.R., W.E. Burgess, N. Pronek and J.G. Walls (1991) Dr. Axelrod's Atlas of freshwater aquarium fishes. Sixth edition. T.F.H. Publications, Neptune City, New Jersey.
Rainboth, W.J. (1996) Fishes of the Cambodian Mekong. FAO species identification field guide for fishery purposes. FAO, Rome, 265 p.
Greenwood, P.H. and M.V.H. Wilson (1998) Bonytongues and their allies. p. 80-84. In J.R. Paxton and W.N. Eschmeyer (eds.) Encyclopedia of fishes. Academic Press, San Diego. 240 p.
Scott, D.B.C. and J.D. Fuller (1976) The reproductive biology of Scleropages formosus (Müller & Schlegel) (Osteoglossomorpha, Osteoglossidae) in Malaya, and the morphology of its pituitary gland. J. Fish Biol. 8(1):45-53.
Vidthayanon, C. (2005) Thailand red data: fishes. Office of Natural Resources and Environmental Policy and Planning, Bangkok, Thailand. 108 p.
Kottelat, M. (2013) The fishes of the inland waters of Southeast Asia: a catalogue and core bibliography of the fishes known to occur in freshwaters, mangroves and estuaries. The Raffles Bulletin of Zoology 2013 (Suppl. 27):1-663.
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