Pike topminnow

Belonesox belizanus

FreshwaterFish

Care at a glance

Temperature: 73–82°F (23–28°C)
pH: 6.5–7.5
Adult size: 7.9 in (20 cm)
Minimum tank: 44 gal (165 L)
Temperament: Mostly peaceful
Social behavior: Social
Swim level: Top
Difficulty: Medium
Breeding: Easy
Rarity: Very rare
Origin: Mexico, Central America
Family: Poeciliidae

Overview

The pike topminnow is a slender surface predator that hangs near the top waiting to ambush smaller fish. It is not aggressive toward tankmates it cannot swallow, but it will eat anything that fits in its mouth, so house it only with robust fish close to its own size, or keep it on its own. A single fish or a small group is fine given space. It is a committed fish-eater and often takes only live food at first, such as surplus livebearers, before it can be weaned onto fresh and frozen meaty foods. It likes warm, neutral to alkaline water. Because adults are large and predatory, give it a tank of 165 liters or larger with a tight lid.

In the wild

Belonesox belizanus lives in the warm lowlands of Mexico and Central America, in still and slow-moving waters such as ditches, ponds, marshes and mangrove edges, often thick with plants. Keep a temperature between 23 and 28 C and a pH from about 6.5 to 7.5, in hard, alkaline water. A large tank with dense marginal and floating plants, open surface for hunting and calm flow suits it. Clean, warm, stable water keeps this predator settled.

Good to know

The pike topminnow is the largest livebearer in the family Poeciliidae, with females reaching about 20 cm and males much smaller. Despite its pike-like jaws it breeds like other livebearers: the male fertilizes the female internally with a gonopodium, and she gives birth to live, fully formed young. A single female can drop a large brood of up to a hundred or more fry, and the species breeds readily, though the tiny predators must be reared apart from the adults.

Did you know

With its long, tooth-lined jaws and ambush habits, the pike topminnow is the only livebearer to have taken up life as a specialised, pike-like fish-eater, and it can swallow prey close to half its own length.