Fish Identifier

Turquoise Rainbowfish Identification Guide

Recognize this Lake Kutubu native by its brilliant solid turquoise-blue sheen and elongated body.

Read the full Turquoise Rainbowfish encyclopedia entry →
Turquoise Rainbowfish Identification Guide

Key identification features

  • Elongated, moderately compressed body reaching about 4 inches (10 cm)
  • Brilliant iridescent turquoise-blue coloring across the flanks, strongest in mature males and visible even in low light
  • Fins tinged pale yellow, unmarked or lightly edged, unlike more colorful relatives
  • Two dorsal fins and a forked tail
  • Silvery-white underside contrasting with the vivid blue back and sides
  • A relatively straight dorsal profile with only a gentle rise toward the first dorsal fin

Common look-alikes

  • Red Rainbowfish: overall red-orange rather than blue, with a more strongly humped back
  • Neon Rainbowfish: much smaller and stockier with bright orange, black-edged fins
  • Australian Rainbowfish: duller olive-blue with faint stripes rather than a solid, even turquoise sheen

Where you'll see one

Endemic to Lake Kutubu and its tributary streams in the Southern Highlands of Papua New Guinea, favoring open water near shoreline vegetation. Large schools are often visible cruising just below the surface on calm days, particularly around midday when light penetrates the clear water.

Frequently asked questions

What single feature best confirms a Turquoise Rainbowfish?

A solid, even turquoise-blue body sheen without the strong fin coloring seen in related species is the clearest sign.

How is it different from the Red Rainbowfish it's often compared to?

Turquoise Rainbowfish are blue rather than red-orange and have a straighter, less humped back profile.