All fish / Zenarchopteridae

Feathered Halfbeak

Zenarchopterus dispar

Also known as feathered river-garfish, spoon-fin halfbeak, halfbeak, garfish halfbeak, zenarchopterus halfbeak, todak, クルメサヨリ, julung-julung, 异鳞鱵

A slim, silvery green halfbeak with a long lower jaw and a short upper jaw, found in mangroves, estuaries and lower river reaches. Males have elongated, feathery rays in the dorsal and anal fins. Keepers value it as an unusual surface dweller for long brackish tanks.

Care at a glance

Care level

Hard

Temperament

Semi

Adult size

15 cm

Temperature

24 to 29 °C

pH

7.5 to 8.5

Smallest tank

200 litres

Keep as

Group of 5 or more, ideally with more females than males

Diet

Carnivore: floating insects such as fruit flies and crickets, live or frozen bloodworm, brine shrimp and mysis; slow to accept dry food

Swims

Top of the tank

Lifespan

3 to 5 years

Water

Brackish

Wild range

Indo-West Pacific: East Africa and Madagascar to Southeast Asia, New Guinea, northern Australia and western Pacific islands

Breeding

Fertilisation is internal, with the male's modified anal fin passing sperm, and the females lay eggs that hang from plants or roots. It is rarely bred in home aquariums, and raising the tiny fry needs very small live foods.

Good to know

Easily startled, so it may leap or hit the glass and damage its beak; use a tight lid and a long tank with open surface water. Males spar with each other, and it may eat very small tankmates.