Pseudacanthicus is a genus of medium to large-sized suckermouth armored catfishes native to South America, where found in the Amazon and Orinoco basins, as well as rivers of the Guianas.

[7][8] Species of Pseudacanthicus are medium to large spiny loricariids, up to 90 cm (3 ft) in standard length.

[2] They have a diverse range of colour patterns, typically light to dark grey or brown, often with black spots, which may result in a netted appearance.

The fins and body may have orange-red sections or a red wash.[1] Colouration varies between rivers and can also change throughout the lifetime of a single individual.

[6] Like many other loricariids, Pseudacanthicus are found in flowing waters with high levels of oxygen and dams typically flood these, transforming them to reservoirs.