Harlequin Shark (Labeo cyclorhynchus) Care Guide
A distinctive large labeo with a velvety black body contrasted by bright orange to red fins. Despite the common name 'shark', it is a cyprinid related to barbs and minnows.
Compiled by Aquairi from published sources · Published · Updated
Overview
Labeo cyclorhynchus is a species in the family Cyprinidae. A distinctive large labeo with a velvety black body contrasted by bright orange to red fins. Despite the common name 'shark', it is a cyprinid related to barbs and minnows. A bottom-dwelling algae grazer that becomes territorial with age, especially toward similar-looking fish.
Taxonomy
- Family: Cyprinidae
- Genus: Labeo
- Scientific name: Labeo cyclorhynchus
- Other names: Variegated Shark, Black Shark
- Origin: Africa, Congo Basin
Habitat
Labeo cyclorhynchus is a cyprinid from rivers of the Congo basin in central Africa. A strongly territorial bottom dweller, it grazes algae and biofilm from rock and wood and aggressively defends a feeding territory, making it best kept singly.
Tank requirements
- Minimum tank volume: 200 L
- Temperature: 23-27 °C
- pH: 6-7.5
- GH: 3-12 °dGH
- Water flow: moderate
- Adult size: 12-15 cm
- Lifespan: 6-10 years
- Difficulty: intermediate
Diet
Classified as omnivore. Recommended feeding frequency: 2x daily. In captivity, offer a varied diet appropriate to the species — quality prepared foods supplemented with frozen or live items of suitable size.
Compatibility
- Temperament: semi-aggressive
- Position in tank: bottom
- Compatible tank mates: Tiger Barb, Congo Tetra, Rainbowfish, Large Gouramis
- Avoid with: Rainbow Shark, Red-tail Black Shark, Other Labeo Species, Slow Bottom Dwellers
Breeding
- Breeding strategy: egg-scatterer
- Breeding difficulty: advanced
Harlequin Shark (Labeo cyclorhynchus) Breeding Guide
Overview
Labeo cyclorhynchus is, as far as is known, not bred in aquaria. It is a strongly territorial cyprinid with a solitary lifestyle, and these traits make pairing and spawning impractical in the home aquarium.
Sexing
Labeo are notoriously difficult to sex. Females should be noticeably thicker-bodied than males when in spawning condition, but outside that condition the sexes cannot be told apart reliably, which is one reason controlled pairing is so hard.
Why It Is Not Home-Bred
Intraspecific aggression is pronounced; it is not uncommon to see tanks full of young specimens with tattered fins on sale, the result of conspecifics fighting. The species maintains a solitary lifestyle and does not tolerate its own kind, so keeping a compatible pair together long enough to spawn is extremely difficult.
Common Challenges
The combination of severe intraspecific aggression, solitary habits and unreliable sexing means there is no established aquarium breeding protocol. Aquarists keeping this fish should focus on housing a single specimen with suitable, non-similar tankmates rather than attempting to breed it.