Merry widow livebearer

Phallichthys amates

FreshwaterFish

Care at a glance

Temperature: 72–86°F (22–30°C)
pH: 7.0–8.0
Adult size: 2.5 in (6.4 cm)
Minimum tank: 16 gal (60 L)
Temperament: Peaceful
Social behavior: Social
Swim level: Middle
Difficulty: Easy
Breeding: Easy
Rarity: Very rare
Origin: Guatemala, Panama
Family: Poeciliidae

Overview

The merry widow is a gentle, easygoing livebearer that suits a peaceful community. Keep a group with more females than males, as males court often, and it will happily share the middle of the tank with other calm species. It grazes soft algae and takes almost any small food, so feed a good flake with some vegetable content plus occasional frozen daphnia or bloodworm. It prefers hard, neutral to alkaline water. It is undemanding and a sound choice for someone new to wild livebearers, and a tank of 60 liters or larger gives a small group plenty of room.

In the wild

Phallichthys amates ranges from Guatemala down to Panama, living in warm, slow to moderate streams, ponds and ditches, often among thick plants. Keep a temperature between 22 and 30 C and a pH from about 7 to 8, with hard, mineral-rich water. A well-planted tank with open swimming areas, gentle flow and steady filtration suits it. It is not fussy, but clean, stable water keeps it healthy and breeding freely.

Good to know

The merry widow belongs to the livebearer family Poeciliidae, with females reaching about 6 cm and males staying smaller. The male is known for an unusually long gonopodium, the modified anal fin used to fertilize the female internally, and this outsized organ gives the genus its name, Phallichthys. Females give birth to live young and breed readily, so this is an easy livebearer for a home tank.

Did you know

The genus name Phallichthys means penis fish, a blunt reference to the male's very long gonopodium, which can reach a large fraction of his own body length.