Potaro

This species may also be seen on sale as 'Guyana slopehead catfish' 'dolphin catfish' or 'hammerhead catfish'. The attractive juvenile patterning is largely lost as the fish grow but this nevertheless remains an impressive predatory species for the larger aquarium. The genus Ageneiosus was at one point classified in the family Ageneiosidae alongside the genus Tetranematichthys, but this was not accepted by all...

A biotope-style set-up could consist of a sandy substrate, piles of smooth rocks and driftwood roots and branches, some of which should penetrate the water surface. Aquatic vegetation can be included if you wish but is likely to be eaten.

Native to Guyana, where it may be restricted to the Potaro River, a major tributary within the Essequibo watershed. It was described from aquarium specimens which were said to have been collected in 'very small water courses of the Amazon', but the type locality was corrected to 'Guyana-Essequibo, Potaro River, Kuribong trail' by Nijssen and Isbrücker (1980).

Type locality is 'Tukeit, Guyana', and this species is known from various river drainages of Venezuela, Guyana, Suriname and French Guiana including the Orinoco, Essequibo, and upper Courantyne (aka Corantijn) basins. Additional records exist from the upper Amazon basin in Guyana, these presumably corresponding to the Takutu river basin, itself part of the upper rio Branco.

Inhabits sluggish blackwater tributaries, small rivers and swampy areas, particularly in areas with dense growth of aquatic or overhanging riparian vegetation, submerged woody structures and leaf litter. The water is typically stained darkly with humic acids and other chemicals released by decaying organic material, the dissolved mineral content is generally negligible and pH can be as low as 4.0. N. minimus occurs sympat...

S. leucosticta is frequently available in the ornamental trade and farmed for the purpose in several countries. It is often confused with its congener S. jurupari in aquarium literature and on websites, but is easily recognised by presence (vs. absence) of prominent white spots or vermiform markings on the sides of the head. Although the presence of white spots on the head does not distinguish it from all known Satanoperca populations (see below), it can...