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Commonly Asked Questions

Appears in Georgia Aquarium's:
  • Southeast Asian Fishes (River Scout)

Range / Habitat

  • Harlequin rasbora occurs in freshwater habitats of Malaysia, Thailand and Singapore.
  • Found in peat swamps and forest pools and streams with lots of cover and plant matter. Decomposing plants add tannins to the water, creating an acidic blackwater environment. 

Physical Characteristics

  • Body coloration is a shiny red-orange, marked by a distinctive black triangle that begins just below the dorsal fin and trails along that caudal peduncle.
  • Occasionally displays a small dark streak behind the operculum.
  • The eyes are very large and round.
  • Harlequin rasbora can grow to 2 inches (5 cm) in length.

Diet / Feeding

  • Diet consists of insects, worms and other small invertebrates.

Reproduction / Growth

  • The female harlequin rasbora is often larger and rounder than the male. 
  • Spawning usually takes place under plant cover; eggs will adhere to the undersides of large leaves.

Conservation Status

  • “Least Concern” on the IUCN Red List.

Additional Information

  • Habitat loss and run-off due to agriculture is the main threat to population in the native habitat. 
  • A schooling species.
  • A peaceful, popular aquarium fish.
  • Previously thought to be a member of the Rasbora genus, harlequin rasbora was renamed Trigonostigma heteromorpha.

Sources

www.fishbase.org
www.iucnredlist.org
www.seriouslyfish.com/species/trigonostigma-heteromorpha