Evidence rule: Trade and color designations are not separate species or proven parent–offspring pedigrees. Exact claims must be checked against cited studies and tagged farm records.
Identity and classification
Species: Scleropages formosus. Record kind: Green phenotype/market designation. Research grade: Directly sampled phenotype. This is not an independent species.
Geographic and historical origin
Broader Asian-green geographic connections; not the South American silver arowana Osteoglossum bicirrhosum.
Appearance and diagnostic issues
Silver-toned body with yellow-tailed appearance in trade language; require adult traits and species ID.
Genetics and lineage evidence
YS shared broad 2n=50 karyotype in the direct study, which does not support assigning it a separate species.
Sampling and scientific support
Directly sampled as Yellow-Tail Silver (YS) among green variants in 2023 cytogenetics. The 2023 direct comparison of five phenotypes found all sampled forms had 2n=50 chromosomes; it did not prove a unique strain-specific gene for any trade name.
Breeding and authentication
For a particular fish, require a PIT/microchip, lawful source documents, claimed breeder/farm, birth cohort, individual parent IDs or documented cross records where available. No advertised grade or photograph alone proves pedigree or genotype.
Care and conservation
As a large surface-oriented male mouthbrooder, Asian arowana needs species-appropriate secure housing and stable water; protected-wildlife trade and import requirements depend on jurisdiction. Do not solicit precise threatened wild collection sites.