Pike Top Minnow (Belonesox belizanus) Care Guide
Belonesox belizanus is a predatory livebearer of the family Poeciliidae from Central America, resembling a small freshwater pike and reaching up to 20 cm.
Compiled by Aquairi from published sources · Published · Updated
Overview
Belonesox belizanus is the only member of its genus and the largest livebearer in the family Poeciliidae. The body is elongated with an upturned lower jaw and a dorsal fin set far back, recalling a small pike. FishBase records a maximum total length of 20 cm.
Taxonomy
- Family: Poeciliidae
- Genus: Belonesox (monotypic)
- Scientific name: Belonesox belizanus
- Authority: Kner, 1860
Habitat
FishBase records the species from Mexico, Guatemala, Belize, Honduras, Nicaragua and Costa Rica, with introduced populations in Florida, USA. It inhabits fresh and brackish waters and tolerates salinity up to 40 ppt.
Tank requirements
- Minimum tank volume: 200 L (53 gal)
- Temperature: 24-30 °C (75-86 °F)
- pH: 7.5-8.5
- GH: 12-25 °dGH
- Lifespan: 3-5 years
- Cover: dense planting and surface structure
Diet
Belonesox belizanus is a piscivore. Wikipedia describes an extremely flexible upper jaw that lets it take large prey for its size. In captivity it requires meaty foods and often live or frozen fish; FishBase notes it is a specialised fish-eater.
Compatibility
This is an aggressive top-water predator that will eat any fish small enough to swallow. It is best kept in a species-only tank; even within the species, smaller individuals may be eaten by larger ones. It is not suited to community settings.
Breeding
The species is a livebearer. FishBase notes broods of up to about 100 young. Females are larger than males, and as with other poeciliids fertilisation is internal with live birth.
Conservation status
IUCN Red List: Least Concern (assessed 2018), per FishBase.
Pike Top Minnow Breeding Guide
Overview
Belonesox belizanus, the pike top minnow or pike killifish, is the sole member of its genus and a highly specialized predatory poeciliid. FishBase records it from Laguna San Julian near Ciudad Veracruz in Mexico south along the Central American coast to Nicaragua, with an introduced population in Florida. It is a non-migratory, demersal fish of weedy canals that tolerates poorly oxygenated water. Unlike most poeciliids it is piscivorous, taking very large prey for its size with an extremely flexible upper jaw. It is a livebearer and, by poeciliid standards, not an easy aquarium resident.
Sexing
Females are considerably larger than males: FishBase gives males to 20 cm total length and females to 15 cm, with a common length of about 9.7 cm. The body is elongated with a flat back and an upturned lower jaw longer than the upper. Males possess a gonopodium, the modified anal fin used to transfer sperm.
Conditioning
As an obligate piscivore the species must be conditioned on live or meaty prey; FishBase records it occupying weedy canals and tolerating poorly oxygenated waters. It accepts a wide range, from 25-37 °C, pH 6.0-8.0 and hardness 9-19 dH, and tolerates salinity up to 40 ppt, so brackish maintenance is possible.
Mating & Gestation
Fertilization is internal via the gonopodium. As a livebearer it produces large broods; FishBase reports up to about 100 young per cycle. Pairing should be done cautiously given the predatory nature and the size difference between sexes: a male is much smaller than a female and should be introduced to a well-fed female to reduce the risk of aggression.
Birth & Fry Care
Fry are born live and, like the adults, are predatory; cannibalism is documented in Belonesox and related livebearing genera, so fry must be separated from adults and from larger siblings. Newly born fry require small live foods of appropriate size to grow on.
Common Challenges
This is a species-tank predator that eats other fish and even its own fry, so dedicated grow-out space and a steady supply of live food are essential. Resource competition at high density increases cannibalism, making generous space and feeding important.