Lake Kurumoi rainbowfish  (Melanotaenia parva)

Classified as Vulnerable (VU) on the IUCN Red List (1).

The rainbowfish are a group of small, freshwater fish with a fairly compressed body, large scales, and, as the name suggests, bright colouration (3). The Lake Kurumoi rainbowfish is quite variable in colour, the male being either pale bluish to purplish, with a black stripe along the side, or silvery, with red speckling and with narrow red lines between each row of scales on the sides. The fins are red (2) (4). As in other rainbowfish, the female is less brightly coloured than the male, with less elaborate fins (2) (3) (4), while young males may be more pinkish-purple in colour, turning brighter orange-red with age (2). The Lake Kurumoi rainbowfish has two dorsal fins, the second of which is longer than the first and lacks spines, and there is also a long anal fin beneath the body (3). Although potentially growing up to about nine centimetres, a maximum length of six centimetres is more usual (2) (4).

The Lake Kurumoi rainbowfish, as its common name suggests, is endemic to Lake Kurumoi, in the Vogelkop Peninsula of Irian Jaya, Indonesia (1) (2) (4) (5).

Like other rainbowfish, the Lake Kurumoi rainbowfish inhabits freshwater. Lake Kurumoi is a small lake, around 500 by 800 metres, and is part of the Yakati River system, located in mountainous terrain at around 400 metres above sea level (1) (2) (4) (5).

Virtually nothing is known about the biology of this species. In general, though, rainbowfish are schooling fishes, and eat a variety of foods, including algae, aquatic insects and small crustaceans. Breeding may occur year-round, or may be stimulated by the rainy season, and the eggs are reportedly laid in aquatic vegetation, hatching after one to two weeks (3).

The main threat to the Lake Kurumoi rainbowfish is habitat alteration due to an infestation of tilapia (1), an invasive fish that has been introduced to many areas as a food source. The beautiful colours of rainbowfish have also made them popular in the aquarium trade (3). The Lake Kurumoi rainbowfish was introduced to this trade in 1999 (2), although the impact on the wild population is unknown. Its restriction to a single lake may also make this species particularly vulnerable to any environmental catastrophe to hit the lake.

There are currently no known conservation measures in place for the Lake Kurumoi rainbowfish. Further research into the species and the threats it faces are likely to be needed before any appropriate conservation action can be taken.

View information on this species at the UNEP World Conservation Monitoring Centre.

To find out more about the Lake Kurumoi rainbowfish see:

• FishBase:
  http://www.fishbase.org/summary/SpeciesSummary.php?id=10514
• Home of the Rainbowfish: Melanotaenia parva:
  http://members.optushome.com.au/rainbowfishes/Parva.htm