Myers' Pearlfish (Cynolebias myersi) — 3-4cm

Overview

The Myers' Pearlfish (Cynolebias myersi) is a rare, beautifully patterned seasonal killifish native to seasonal freshwater pools and wetlands in South America, likely Brazil. Reaching just 3cm in length, this peaceful species is prized for its compact size and fascinating breeding behavior. As an annual killifish adapted to temporary habitats that dry seasonally, Cynolebias myersi has a compressed life cycle and unique reproductive biology. Available for sale UK from Tropical Fish Co, this rare species rewards experienced aquarists seeking a compact, specialized species with captivating patterns and behavior.

Appearance and Coloration

Myers' Pearlfish displays exquisite pearl-like colouration with a compact, slender body adorned in intricate patterns of blue, green, and yellow with iridescent pearly spots scattered across the scales. Males are intensely coloured with pronounced finnage and a bold presence, especially during courtship. The fins feature delicate 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 pearly spots become even more visible and eye-catching.

Natural Habitat

Cynolebias myersi inhabits seasonal freshwater pools and wetlands in South America, though the exact locality is not well documented in trade sources. These temporary water bodies fill with water during the wet season and dry completely during the dry season. The water is typically soft, slightly acidic, 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 months later.

Aquarium Setup

A minimum 20-litre aquarium is sufficient for a pair or small group of Myers' Pearlfish. 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 warm temperatures (23-28°C) to replicate natural conditions.

Feeding and Diet

As a carnivore, Cynolebias myersi requires a varied, protein-rich diet to maintain health and colour. Offer small live and frozen meaty foods such as bloodworms, daphnia, brine shrimp, and insect larvae daily. High-quality carnivorous prepared foods may be accepted after acclimation, but live and frozen foods are preferred 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

Myers' Pearlfish 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

Cynolebias myersi is best kept species-only to accommodate its unique breeding biology and short lifespan. If tankmates are used, only very small, peaceful, non-competitive fish with identical water needs and no risk of outcompeting the killifish should be considered. Avoid large or boisterous fish, aggressive species, fast-feeding community fish, fin-nippers, and very small shrimp or fry. A calm, quiet environment is essential for this delicate annual killifish to thrive.

Breeding

This seasonal killifish is typically bred by providing a soft, shallow spawning substrate for egg deposition. 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 drying/incubation period before hatching, depending on the strain and conditions. Collect eggs carefully and store in slightly damp peat in a sealed container at warm room temperature. Fry hatch when the peat is re-flooded and require infusoria or newly hatched brine shrimp. Breeding success depends on careful egg management and precise water conditions.

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 Cynolebias myersi. 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 South American annual killifish.