Melanotaenia rubrostriata

Melanotaenia rubrostriata - photo© Gunther Schmida

(Ramsay and Ogilby, 1886)
Red-striped Rainbowfish

Species Summary
Melanotaenia splendida rubrostriata have a basic body colouration of overall pale bluish-green, grading to white on the lower sides. Each horizontal scale row is separated by a narrow orange to pink stripe. The membranes between the rays of the second dorsal and anal fin are red. Not easily distinguished from Melanotaenia splendida inornata. Principal differences are body depth, fin counts, and colour pattern, which is variable depending on location and water conditions. Melanotaenia splendida rubrostriata may reach a maximum size (TL) of 16 cm, but usually less than 12 cm, with a body depth of 6-8 cm. Males are more brightly coloured, larger, and much deeper bodied than females.

Distribution & Habitat
Melanotaenia splendida rubrostriata were initially collected during the 1880s from the Strickland River, Papua New Guinea. They are widely distributed in southern New Guinea between Etna Bay in West Papua and the Central Province of Papua New Guinea. The Kikori River was the previous eastern limit of distribution, but recent surveys indicate that they are more widespread; having been collected in the Sapoi River in the Lakekamu Basin. The Lakekamu Basin covers 2500 km² of pristine lowland rainforest, surrounded in the east, west and north by mountains. The northern, mountainous part lies in Morobe Province while the lower part is divided among two provinces, the western half belonging to Central Province; the eastern half is a part of Gulf province. The Sapoi River drainage is located approximately 150 km northwest of Port Moresby. They have also been found on the Aru Islands.

Melanotaenia splendida rubrostriata inhabit freshwater creeks and rivers along lowland coastal plains. They are usually found around sub-surface vegetation, submerged logs, or branches. Temperature and pH recorded in their natural habitats range from 24~33°C and 5.6~7.5.

Currently known locations: Fly River, Lakekamu River, Sapoi River, Laloki River, Timika, Bensbach River, Etna Bay, Aru Islands, Daru Island, Aramia River, Ok Tedi River and Kemp Welsh River.

Melanotaenia rubrostriata (wild-caught) - photo© Neil Armstrong

Remarks
Melanotaenia splendida rubrostriata were one of the earlier New Guinea rainbowfishes to be introduced to the aquarium hobby. They first appeared in the Australian hobby around 1959. Live specimens were also collected by Gerald Allen during the period 1978~1982. I obtain my first specimens in 1979 (Kemp Welsh River) and maintained a small population until 1983. This was another rainbowfish that fell out of favour with hobbyists as the number of new species arrived from New Guinea, and much of the captive stock disappeared.

Literature
Allen, G.R. (1991). Field guide to the freshwater fishes of New Guinea. Christensen Research Institute, Madang, Papua New Guinea.

Ramsay, E. P. and J. D. Ogilby (1886). A contribution to the knowledge of the fish-fauna of New Guinea. Proceedings of the Linnean Society of New South Wales (Series 2) Volume 1: 8-20.