Ageneiosus

The manduba, Ageneiosus inermis, is a large auchenipterid catfish found throughout much of South America east of the Andes. At around 470 mm SL it would need an aquarium in excess of 400 x 120 cm as an adult and is largely unsuitable for private aquaria. An obligate carnivore, it can take surprisingly large prey, and the larger Ageneiosus species are often used as food fishes in their native countries.

The bottlenose catfish, Ageneiosus marmoratus, is a predatory auchenipterid catfish from Guyana, Suriname and the upper Amazon in Peru and Ecuador. Also sold as 'Guyana slopehead', 'dolphin' or 'hammerhead' catfish, it loses much of its black-blotched juvenile patterning as it grows. Surprisingly peaceful with anything too large to swallow, it is active and sometimes skittish, and needs a tank of at least 150 x 60 cm.

The duck catfish, Ageneiosus ucayalensis, is an auchenipterid catfish described from Peru and recorded across the Amazon, Orinoco and Guianas. Body patterning apparently varies with locality, and fish from black water habitats, particularly on the Guiana Shield, tend to be darker. Growing to around 290 mm SL and capable of taking large prey, it is safe only with similarly sized catfishes or large pelagic characins, mostly a combination for public aquaria.