The threadfin rainbowfish or featherfin rainbowfish (Iriatherina werneri) is a rainbowfish, the only species in the genus Iriatherina. It is characterized by long beautiful fins, and is among the most attractive of the rainbowfishes.
It is native to freshwater swamps and demersal or thickly vegetated areas of flowing waters, in tropical Australia, the West Papuan region of Indonesia, and Papua New Guinea.
It grows up to 5 cm (2.0 in) in length, but this does not include the Threadfin's long tail. Sexing is easy by examining fins: males have larger, gaudier finnage than females. Males also have more intense colours. When reproduction takes place eggs are scattered among fine leaved plants, and hatch after 8â€"12 days.
In the aquarium
In aquaria they are usually peaceful, they live preferably in groups of six or more. Because of their long fins they should obviously be kept in a tank without fin-nippers. They breed best in tanks without other species. The male courts the female by posturing in front of her repeatedly quickly raising then lowering the forward dorsal fin.
Threadfin Rainbowfish do well in aquariums of 20 US gallons (76Â L), however 30 US gallons (110Â L) is preferred. They are best housed in a "species only" tank; meaning that the tank is reserved for the Threadfins alone. Because of their tiny mouths, they can be difficult to feed. They do well with live foods, such as baby brine shrimp, and the micrometre larval diets.
They prefer water that is soft to moderately hard, slightly acidic (pH 6.0â€"7.0), and with a temperature of 23â€"29 °C (73â€"84 °F).
References
- "Iriatherina werneri". Integrated Taxonomic Information System. Retrieved 11 March 2006.Â
- Froese, Rainer and Pauly, Daniel, eds. (2005). "Iriatherina werneri" in FishBase. 10 2005 version.