Chilatherina bleheri - photo© Neil Armstrong

Chilatherina bleheri

Species Summary
Chilatherina bleheri is a very attractive rainbowfish. They generally have a silvery or greenish body colour on the upper back fading posteriorly to pastel shades of yellow to red. The scales on the front half of body, particularly on the dorsal region, have broad yellow-green margins; the first dorsal fin charcoal grey; second dorsal fin grey suffused with red; caudal and anal fins red; pelvic fins reddish anteriorly with remainder white or translucent; pectoral fins translucent. The lower side of the body is white with a series of faint vertical dark markings. Females lack the vivid red hues and are mainly silvery or blue bluish grading to grey or greenish-brown. Males display a brilliant yellow-orange stripe on the middle of the forehead during spawning. Males are larger than females with older males developing a very deep body. Males may reach a maximum size of 12 cm, but females are usually less than 10 cm. Chilatherina bleheri are essentially a carnivore, feeding on a variety of terrestrial and aquatic insects, insect larvae, and small aquatic crustaceans. Aquatic algae and fallen plant pollens are also ingested.

Distribution & Habitat
Chilatherina bleheri have been collected from the vegetated shoreline and feeder streams of Lake Holmes (Danau Bira) situated in the Mamberamo region of West Papua. Lake Holmes is a complex of three interconnected lakes lying at an altitude of about 430 metres above sea level and set in the foothills of the van Wees Mountains, approximately 290 kilometres west of Jayapura, the capital city of West Papua. The lakes lie within a radius of 6~7 kilometres with the main lake having a length of approximately 4.5 kilometres and maximum width of about 2 kilometres. The lakes are drained by a small stream, which flows into the Mamberamo River at a point approximately 15 kilometres directly to the north. The lake and surrounding creeks are inhabited by 11 fish species, including one other rainbowfish, Melanotaenia maylandi.

Remarks
Live specimens of this species were initially collected by Gerald Allen and Heiko Bleher in 1982. When first discovered it was thought that they were just another colour variety of Chilatherina fasciata. The two species differ primarily with respect to size of scales and male colouration. Chilatherina bleheri have smaller scales. However, in 1985 they were described by Gerald R. Allen as a new species and named in honour of Heiko Bleher, a well-known fish collector.

Literature
Allen G. R. (1985). Three New Rainbowfishes (Melanotaeniidae) from Irian Jaya and Papua New Guinea. Revue Française d'Aquariologie 12 (2): 53-62.

© Copyright Adrian R. Tappin
Updated December, 2008.