(Oxydoras niger)
The ripsaw catfish (Oxydoras niger) or cuiu cuiu is a species of thorny catfish native to the Amazon, Essequibo and São Francisco basins in Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru and Venezuela. This species grows to a length of 100 centimetres (39 in) SL and weights up to 13 kilograms (29 lb). This species is a minor component of local commercial fisheries. Has lateral thorns that can damage a potential predator or handler. It feeds by shifting through sand and detecting eatable parts with the taste receptors in the roof and floor of its mouth.