Fly River rainbowfish (Melanotaenia sexlineata)

Scientific name: Melanotaenia sexlineata Munro, 1964

The Fly River rainbowfish (Melanotaenia sexlineata) is a freshwater fish of the family Melanotaeniidae. In the aquarium it needs water at 24–26°C (75–79°F). Native range: Oceania, known only from a few sites in the upper Fly River system near Kiunga, Papua New Guinea.

Fly River rainbowfish care at a glance

Temperature: 24–26°C (75–79°F)

Biology

Dorsal spines (total): 6 - 8; Dorsal soft rays (total): 10-12; Anal spines: 1; Anal soft rays: 16 - 19

Source: FishBase, licensed CC BY-NC 4.0.

Species facts

Scientific name: Melanotaenia sexlineata
Family: Melanotaeniidae (Rainbowfishes, blue eyes)
Order: Atheriniformes (Silversides)
Class: Actinopterygii (Ray-finned fishes)
Maximum length: 7.0
Environment: Freshwater;; pH range: 7.0 - 7.5 benthopelagic
Climate: Tropical
Distribution: Oceania: known only from a few sites in the upper Fly River system near Kiunga, Papua New Guinea.
Conservation status (IUCN): Data deficient (DD)
Threat to humans: Harmless
Uses: Fisheries: of no interest
Resilience: Medium, minimum population doubling time 1.4 - 4.4 years (Preliminary K or Fecundity.)

Sources

Taxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.

Last updated 27 September 2026