内格罗河兵鲶

Overview

The peaceful catfish Hoplisoma duplicareum has a dark oblique back marking and a bright orange nape patch. It closely resembles Hoplisoma adolfoi, and differences in color alone do not reliably separate them.

Distribution & habitat

Confirmed records cover only a small part of Brazil's upper Negro system, with the type locality in the Poranga. Fast water and sand were recorded during collection. Wider use of blackwater tributaries and flooded forest is presumed rather than fully established.

Aquarium setup

Fine sand is preferable; smooth gravel requires careful cleaning. Wood and dried leaves provide shelter, with developing microorganisms offering supplementary food for fry. Gentle filtration is adequate, although some current is acceptable. A fast-flowing collection site does not establish a requirement for forceful aquarium circulation.

Diet & feeding

Offer varied sinking foods alongside small live or frozen items such as bloodworms and Tubifex. This omnivorous feeder needs deliberate meals, not dependence on leftovers from other fishes.

Behaviour & compatibility

Keep at least four to six conspecifics. Calm group maintenance should include shelter and dependable access to food.

Sexual dimorphism

Females generally become larger and broader, particularly when carrying eggs.

Breeding

Egg deposition has been reported on the substrate and near the waterline. These reports do not supply a complete species-specific incubation or fry-rearing schedule.

Notes

A broader dark bar and stronger orange patch are tendencies rather than reliable identification criteria. Serrations along the rear edge of the pectoral spine provide a finer distinction, but they are difficult to see without magnification. Avoid rough handling for inspection.

Occasional air gulps provide auxiliary respiration. Stiff pectoral spines can snag nets or puncture skin, and suggested mild toxicity of nearby gland secretions remains uncertain.