Golden Pterolebias

Adults reach 12 cm in length. Because they are widespread in nature, many local colour variants exist. Males are always more brightly coloured and have larger fins decorated with spots that match the base colour. Their colouration ranges from silver to yellow, pink, and red. Females are usually grey. In the wild these fish live for only one season, lasting from a few months to half a year, depending on how long the temporary pool persists. In that short time they complete their entire life cycle: hatch, grow, and reproduce. Fertilized eggs remain in the silt of the dried pool for several months, waiting for the rains to return. In the aquarium their lifespan usually exceeds one year.

This fish inhabits the floodplains of major South American rivers, including the Amazon and Paraguay basins. The golden pterolebias lives in temporary pools and puddles that form during the rainy season.

Because they live in pools that dry up, these fish rarely have tank mates in nature. Occasionally other killifish species share their habitat. For this reason, keep them in a species tank. Males compete for female attention and may fight, but this rarely causes serious injury. To keep peace, form a group of one male and several females: the females are quite peaceful.

The golden pterolebias is hardy and undemanding. Keeping these annual fish usually aims at breeding and maintaining the population. Use a soft fibrous substrate such as coconut fibre or similar material: its purpose is to preserve the eggs and allow you to remove it completely from the tank. The rest of the setup may include driftwood, branches, floating plants, and a layer of fallen leaves. A simple air-driven sponge filter is usually adequate; other systems are unnecessary. Artificial lighting is optional—room light is enough. The diet should consist of live or frozen foods such as bloodworms, brine shrimp, or daphnia.

The diet should consist of live or frozen foods such as bloodworms, brine shrimp, or daphnia.

These fish breed readily in the aquarium, but the main challenge is preserving the eggs properly. Mature golden pterolebias bury their eggs in the substrate. In the wild they dig slightly into soft substrate to protect the eggs. Remove the substrate containing the eggs and let it dry. Before drying, rinse the substrate carefully but thoroughly to remove food waste, faeces, and other organic matter—otherwise mould and fungus will likely develop. The incubation period lasts 3 to 6 months depending on temperature and humidity. Higher temperature and moist substrate speed up incubation, but excessive moisture can kill all the eggs. Stimulate spawning by raising the temperature to 24–28 °C. After incubation, place the substrate with eggs in a tank with water at about 20–21 °C. Fry appear within a few days.

Like other annual killifish, this species is sensitive to water quality and keeping conditions. Poor temperature control and accumulation of organic waste are the main disease triggers. Water temperatures above 23 °C shorten lifespan and weaken immunity, making the fish prone to bacterial and fungal infections. Prevention relies on regular water changes and stable parameters. These fish tend to injure each other in conflicts, so provide shelter to prevent fin damage and the infections that follow.

When choosing fish, look for activity and intact fins. Healthy golden pterolebias should show interest in their surroundings and respond eagerly to food. Avoid fish that look thin, have sunken bellies, or show skin damage. Young fish can be quite aggressive, so assess the group's behaviour in the shop: heavily bitten fins suggest poor keeping or overcrowding. Buy from established breeders to ensure you get healthy fish that adapt well to the aquarium.