Pterygoplichthys multiradiatus is a tropical fish known as a Plecostomus belonging to the armored catfish family (Loricariidae). Named for its sail-like dorsal fin, the part of its scientific name multiradiatus means "many-rayed" and refers to the rays of the dorsal fin. P. multiradiatus is one of a number of species commonly referred to as the common pleco by aquarists.