Argentine Pearl (Austrolebias bellottii) — 3-5cm

Overview

The Argentine Pearl (Austrolebias bellottii), also known as the Argentine Pearlfish, is a beautifully patterned Argentine annual killifish native to seasonal pools and floodplain wetlands in the Paraná and Uruguay river basins. Reaching 5cm in length, this peaceful species is prized for its unique behaviour, delicate care requirements, and fascinating breeding biology. As an annual killifish adapted to temporary habitats that dry seasonally, Austrolebias bellottii has a compressed life cycle and unique reproductive strategy. Available for sale UK from Tropical Fish Co, this rare species rewards dedicated keepers with stunning patterning and captivating behaviour.

Appearance and Coloration

The Argentine Pearl displays exquisite colouration with a slender, elegant body adorned in intricate patterns of blue, green, and yellow with pearl-like iridescent spots scattered across the scales. Males are intensely coloured with elongated finnage and a bold presence, especially during courtship. The fins feature intricate patterning and iridescent highlights that shimmer under subdued lighting. Females are smaller, plumper, and more subdued in colour with shorter finnage. In a planted tank with dark substrate, the colours and patterns become even more vibrant and eye-catching.

Natural Habitat

Austrolebias bellottii occurs in seasonal pools and floodplain wetlands in the Paraná and Uruguay river basins of Argentina and Uruguay. These temporary water bodies fill with water during the wet season and dry completely or nearly dry during the dry season. The water is typically soft, slightly acidic to neutral, and well-vegetated, with a substrate of mud and organic debris. During the wet season, adults spawn rapidly; as pools dry, adults perish while eggs remain dormant in dried substrate, hatching when rains return.

Aquarium Setup

A minimum 40-litre aquarium is recommended for a pair or small group of Argentine Pearl. Use a fine sand or soft peat substrate to replicate the natural spawning medium. Include live plants such as Cryptocoryne, Java moss, and floating species like Salvinia or Limnobium. Provide spawning mops or peat moss for egg deposition. Lighting should be subdued, and filtration gentle to avoid strong currents. A secure, tight-fitting lid is essential. Maintain excellent water quality and cooler temperatures (20-26°C) to replicate natural conditions.

Feeding and Diet

As a carnivore, Austrolebias bellottii requires a varied, protein-rich diet to maintain health and colour. Offer small live and frozen foods such as bloodworms, daphnia, brine shrimp, blackworms, and other meaty microfoods daily. High-quality prepared foods may be accepted, but the species thrives on varied protein-rich fare. Live and frozen foods are essential for conditioning and breeding. Feed small portions twice daily, removing uneaten food promptly to maintain pristine water quality. Variety and freshness are critical for optimal health and vibrant colouration.

Behaviour and Temperament

The Argentine Pearl is a peaceful species that spends most of its time exploring the lower and middle water column. Males may display to each other during courtship with flared fins and vibrant colour displays, but serious aggression is rare. These fish have a naturally short lifespan of typically 6-12 months, reflecting their annual biology. They appreciate a dimly lit aquarium with plenty of cover. They are not competitive feeders, so avoid housing them with boisterous or fast-moving species.

Suitable Tank Mates

Austrolebias bellottii is best kept species-only to accommodate its unique breeding biology and short lifespan. Possibly suitable with very peaceful, similarly sized fish in a larger, carefully managed setup, but this is generally not recommended. Snails are safe companions. Avoid large fish, aggressive fish, fin-nippers, very active boisterous species, and tiny shrimp or fry that may be eaten. A calm, quiet environment is essential for this delicate annual killifish to thrive.

Breeding

This annual killifish typically spawns in soft substrate or peat. Condition a pair or small group with high-quality live foods, then provide spawning media such as peat moss or fine sand. Eggs often require a dry incubation period before hatching when water is reintroduced. Collect eggs carefully and store in slightly damp peat in a sealed container at cool room temperature. Fry hatch when the peat is re-flooded and require infusoria or newly hatched brine shrimp. Breeding is usually easiest in a species-only setup with careful egg management.

Why Buy from Tropical Fish Co

Tropical Fish Co is a trusted UK supplier of rare and specialist tropical fish, including hard-to-find annual killifish species like Austrolebias bellottii. We guarantee healthy, well-conditioned stock, expert care advice, and secure nationwide delivery. Every fish is quarantined and inspected before dispatch, ensuring you receive only the finest specimens. Whether you're setting up a dedicated killifish tank or adding a rare species to your collection, Tropical Fish Co offers unmatched quality and customer service. Order online today and experience the beauty of Argentine annual killifish.