|
 |
| Melanotaenia praecox - photo© Hristo Hristov |
(Weber and de Beaufort, 1922)
Neon Rainbowfish
Description
Both sexes are bright neon blue with males having red dorsal, anal, and caudal fins. Heiko Bleher reported in Aqua Geögraphia that "... males have red-edged fins while the fins of females are pure yellow". However, my original females had red fins and succeeding generations are still producing red-finned females, although at times they can appear faintly orange coloured. There are however, aquarium stocks that have yellow-finned females. Another colour variety from Siewa was found in 1998 and differs from the Mamberamo variety in having a red stripe between each scale row. Siewa males do not get so deep-bodied.
Distribution
Melanotaenia praecox are native to the Mamberamo River system, which forms one of the largest river systems in New Guinea. The river system, which is more than 2000 km in length, and up to 1 km wide in places, almost floods the entire river basin during the rainy season. Their occurrence was known only from two small localities near the airstrips at Dabra and Iritoi on the edge of the Mamberamo Plains. In 1998 they were also found in swampy habitats near Siewa, a remote area of northern West Papua about 200 km west of the Mamberamo River Basin.
Initially collected by Dutch naturalists in 1920 from a tributary of the Mamberamo River, West Papua. Until 1992, no one had any proper idea of the living colours of the preserved specimens as they lay in the Zoological Museum of the University of Amsterdam. During that year, Gerald Allen was able to photograph some specimens collected by a pilot from the Danau Bira Mission, who was a keen rainbowfish enthusiast. Then in 1993, Heiko Bleher, under extremely challenging conditions, managed to collect 12 live specimens in a 2 metre wide tributary of the Uge River in the Mamberamo Valley.
Habitat & Ecology
Melanotaenia praecox were found in clear, swift flowing streams and swampy habitats usually around sub-surface vegetation, submerged logs, or branches. May reach a maximum size of 8 cm, but usually less than 6 cm SL. Spawning females produce between 20-50 eggs each day for several days. Eggs adhere to fine-leaved plants or among the roots of floating vegetation. Hatching occurs in about 7 to 8 days at temperatures between 24-28° Celsius.
Remarks
Melanotaenia praecox will display their best colouration if their aquarium is well planted with shaded areas. Bright overhead lights will washout their beautiful blue reflective colour. However, floating water sprite or duckweed are easily grown and will reduce the glare from overhead lights.
© Copyright Adrian R. Tappin
Updated July, 2007.
|
|
