Melanotaenia dumasi
Omba Rainbowfish
Species Summary
Melanotaenia dumasi was described by Max Weber in 1907 from specimens collected on the 1903 Netherlands New Guinea Expedition, but was subsequently treated as a synonym of the widespread M. goldiei and effectively disappeared from use for over a century. Genetic and colour-pattern evidence presented alongside the description of five new ‘Goldiei’ group species in 2016 confirmed it as a distinct, valid species restricted to the Omba (Urama) river system, and it was formally resurrected in that paper.
Etymology
The species’ patronym was not identified by Weber, but is almost certainly in honour of Johannes Maximiliaan Dumas (1856–1931), a feather merchant, surveyor and self-taught naturalist who collected (mostly birds) in West Papua, Indonesia, where this rainbowfish occurs.
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 dumasi is known only from the Omba river system of West Papua Province, including streams around Lake Yamur, where it is common in small creeks flowing into the main lake. The lectotype was collected from the Wa Udu River, the lake’s main outflow, which joins the Omba River about 7 km downstream before the river winds a further 165 km to the Arafura Sea.
Description & Comparison with Similar Species
Live adult males are greyish with a coppery sheen on the back, shading to whitish anteroventrally and blue posteroventrally, with a dark blue-to-blackish mid-lateral stripe flanked immediately above and below by a bright orange-red stripe — the feature that most readily distinguishes Melanotaenia dumasi from its Birds Neck relatives. It also has the highest average number of prepelvic scales and the narrowest average interorbital width recorded for the group.
Account compiled for Home of the Rainbowfish from G. R. Allen, P. J. Unmack & R. K. Hadiaty (2016), “The Goldiei group of rainbowfishes from the Birds Neck Region with descriptions of five new species and recognition of Melanotaenia dumasi Weber”, aqua, International Journal of Ichthyology, 22(1): 1–32.
References
- Allen G.R., P.J. Unmack and R.K. Hadiaty (2016) The Goldiei group of rainbowfishes from the Birds Neck Region with descriptions of five new species and recognition of Melanotaenia dumasi Weber. aqua, International Journal of Ichthyology, 22(1): 1-32.