Melanotaenia picta
Painted Rainbowfish
Species Summary
The Aru Archipelago, a cluster of islands on the shallow continental shelf between New Guinea and northern Australia, was largely overlooked by ichthyologists for a century after Dutch collectors first sampled its rivers in 1907–09. Aquarium enthusiast Heiko Bleher brought Aru rainbowfishes to hobbyist attention after visits in 2004 and 2007, and two expeditions in 2013 (organised by Gerald Allen, Mark Erdmann and colleagues, with genetic work by Peter Unmack) revealed the islands to be an unexpected hotspot of rainbowfish speciation: seven species in all, most found nowhere else. Heiko Bleher first discovered Melanotaenia picta in 2007 in the Mareremar river system, and wild-caught males he brought into the aquarium hobby were still thriving in captivity in Germany years later. It is the most slender-bodied member of the Aru ‘Goldiei’ group.
Etymology
The species name picta is Latin for painted, referring to its beautiful colour pattern.
Etymology compiled from C. Scharpf (2022), “Fishes of Sahul: An Etymological Survey (Part 5), the rainbowfishes (continued)”, Fishes of Sahul 36(4): 1968–1992, and etyfish.org.
Distribution & Habitat
Melanotaenia picta is known from two sites 3 km apart in the Mareremar River system of northwestern Kobroor Island, among the most scenic freshwater habitats found on the Aru Islands: small, crystal-clear rainforest brooks with quiet pools interspersed with cascades up to 3–4 m high, over smooth limestone with abundant log-snag shelter.
Description & Comparison with Similar Species
Live males are blue-grey on the head and back, with a blood-red spot on the upper operculum, and the side of the body blue to pale grey with most scales edged in golden yellow, forming a large golden patch behind the pectoral fin. It is readily told from its Aru relatives M. kolaensis, M. senckenbergianus and M. wokamensis by this overall bluish colouration with extensive golden-yellow highlights, and by its slender body: adult males rarely exceed 30% SL, distinctly less than the 31–32% SL typical of the other three species.
Account compiled for Home of the Rainbowfish from G. R. Allen, R. K. Hadiaty, P. J. Unmack & M. V. Erdmann (2015), “Rainbowfishes of the Aru Islands, Indonesia with descriptions of five new species and redescription of M. patoti Weber and M. senckenbergianus Weber”, aqua, International Journal of Ichthyology, 21(2): 71–106.
References
- Allen G.R., R.K. Hadiaty, P.J. Unmack and M.V. Erdmann (2015) Rainbowfishes (Melanotaenia: Melanotaeniidae) of the Aru Islands, Indonesia with descriptions of five new species and redescription of M. patoti Weber and M. senckenbergianus Weber. aqua, International Journal of Ichthyology 21(2): 66-108.