Sungai Fly basin

Apparently restricted to the southern portion of New Guinea, between the Lorentz River in Papua province, Indonesia, and Kikori River in Gulf province, Papua New Guinea. The majority of records pertain to the lower Fly River basin in Western province, southwestern Papua New Guinea.

There also exists a sister-group relationship between the Melanotaeniidae and Malagasy family Bedotiidae, which may seem surprising given their respective modern-day distributional patterns. The precise origin and subsequent dispersal of the two families has been the subject of debate, with some palentologists suggesting that Madagascar's freshwater fishes derived froma trans-oceanic dispersal during the Cenozoic Era, but the most compelling arguments currently indicate a freshwater radiation which occurred during the Mezozoic break-up of Gondwana.

Type locality is ‘Nicol Bay, Cape York, Queensland, Australia’, and this species is restricted to the tips of northern Australia and southern Papua New Guinea. In Australia records exist only from the Jardine and Jackson river systems on the Cape York Peninsula, while in Papua New Guinea it’s known from the Fly River plus some other drainages.

Described from 'Rivulet in sago forest at Ngaiguli, Terangan, Aru Island, Aru Islands, Maluku, Indonesia', corresponding to the island now normally referred to as 'Trangan' in the Aru Islands group, eastern Indonesia. The islands are located in the Arafura Sea, with western New Guinea to the north and the Arnhem Land Region of Australia's Northern Territory to the south, and though they lie within Maluku province of eastern Indonesia, are part of the Australian continent in a geological sense.