Type locality of Melanotaenia mairasi, West Papua Province, about 15 km northeast of Kaimana. Known only from Lake Furnusu, which lies ca. 15 km northeast of Kaimana, West Papua Province, situated at an elevation of 15 m and is only about 1.5 km from the sea, separated by a steep ridge that rises to an altitude of about 50-550 m. This lake occupies a scenic basin that is approximately 5 km long and 1 to 2 km wide, completely surrounded by steep ridges without any connection to the nearby sea. The drainage appears to be subterranean, typical for other lakes in this region that consists of rugged limestone karst. Water level at the time of collection was extremely high and most of the basin was filled with a large continuous lake and swampy margins (Ref. 87110). Also Ref. 87661.