Pterygoplichthys pardalis is a freshwater tropical fish in the armored catfish family (Loricariidae). It is one of a number of species commonly referred to as the common pleco or "leopard pleco" by aquarists. It will grow to a maximum length of 42.3 centimetres (16.7 in) SL. Pterygoplichthys pardalis is sometimes confused with the Hypostomus plecostomus (another armored catfish known as the "common plecostomus"). The two species can be distinguished by their number of dorsal rays. P. pardalis has 11–13, while the H. plecostomus has only 5–8 dorsal rays.