黑带兵鲶 · Green-gold Cory

Overview

An elongated body and golden-yellow fins help identify Osteogaster melanotaenia, formerly widely placed in Corydoras. This peaceful social catfish needs direct feeding and a clean bottom, not a role as a leftover scavenger. It also prefers cooler conditions than many South American aquarium fishes.

Distribution & habitat

The species occurs in Colombia's Meta basin, using small tributaries, creeks, flooded forest, and sandy banks.

Aquarium setup

River sand, branches, roots, and a modest layer of dried leaves create a suitable setting under subdued light. Wood and leaves can tint the water lightly; replace old leaves before they foul it. A well-maintained planted aquarium is another option.

A tank at least 45 cm long can accommodate a small group. Keep the substrate clean, since deteriorating conditions can damage the barbels. Undergravel filtration is unsuitable. Avoid assuming it requires the warmer temperatures typical of many tropical communities.

Diet & feeding

Use quality sinking pellets or tablets for this omnivore, adding live or frozen Daphnia, Artemia, bloodworms, and similar foods. Ensure sufficient food reaches the fish rather than relying on scraps missed by tankmates.

Behaviour & compatibility

Avoid large or aggressive companions. Small characins, cyprinids, anabantoids, dwarf cichlids, and mild catfishes are possibilities if their environmental needs match. A group of at least six generally behaves more confidently and actively than isolated individuals.

Sexual dimorphism

Females appear broader and rounder from above, especially when carrying eggs.

Breeding

A separate tank may have a bare floor, sand, or fine gravel, with moss or other fine vegetation. Air-driven sponge or box filtration protects tiny fry. Use more males than females, for example two males per female, and condition them with varied foods. Once females are full of eggs, a cooler water change of around 50–70%, together with increased oxygenation and circulation, can stimulate spawning. Maturity and effective triggers can vary.

Courtship culminates in the familiar T-shaped position. The female holds usually one egg, occasionally up to four, in a basket formed by her pelvic fins, then attaches it to a selected surface. Aquarium glass exposed to water movement is commonly used. The proposed route by which sperm reaches the eggs remains an interpretation rather than certainty.

Adults may eat eggs, so separate either the breeders or clutch. Transferred eggs need matching water and good oxygenation. Remove fungused eggs promptly and manage fungal losses during incubation. Hatching takes about 3–5 days. After the yolk is absorbed, offer microworms or Artemia nauplii. A thin sand layer appears to improve rearing health compared with a completely bare floor.

Notes

Bony plates replace ordinary scales. Sharp pectoral spines can snag in nets or pierce skin, requiring care during transfer. Occasional trips to gulp air are normal; a marked increase warrants checking water conditions and oxygenation. Compared with the similar Osteogaster aenea, it is more elongated and shows more golden coloration in the fins.