Argentine pearlfish

Austrolebias bellottii

Also known as Argentine pearl killifish, Bellotti's pearlfish, Cynolebias bellottii

FreshwaterFish

Care at a glance

Temperature: 61–75°F (16–24°C)
pH: 6.5–7.5
Adult size: 2.8 in (7 cm)
Minimum tank: 14 gal (54 L)
Temperament: Aggressive
Social behavior: Solitary
Swim level: Bottom
Difficulty: Medium
Breeding: Medium
Rarity: Rare
Origin: Native to seasonal pools and marshes of the Rio de la Plata basin in Argentina and Uruguay.
Family: Rivulidae

Overview

This is a large, predatory annual reaching about 7 cm, so give a pair or trio a 54 litre or larger species tank at 16 to 24 C and pH 6.5 to 7.5. Males are aggressive toward each other and will eat small tankmates, so keep it alone. Feed meaty live and frozen foods such as blackworm, bloodworm, chopped earthworm, and brine shrimp. Spawn over a deep peat layer that the pair dive into.

In the wild

It lives in temporary pools and flooded grassland on the temperate South American pampas that dry up in summer. Males are deep bodied and dark blue-grey with rows of light pearly spots, and they are much larger and bolder than the plain females. Give it a dark, soft substrate, cooler conditions, and a well covered tank.

Good to know

Austrolebias bellottii is an annual killifish from a temperate climate, so it does best cooler than tropical species and can take a winter dip toward the high teens Celsius. Its eggs survive the dry season buried in mud through diapause. It was long known under the older genus name Cynolebias.