Plecostomus, pleco, or plec is the common name of several species of freshwater loricariid catfish commonly sold as aquarium fish.
- Hypostomus plecostomus
- Hypostomus punctatus
- Pterygoplichthys multiradiatus
- Pterygoplichthys pardalis
- Panaqolus maccus
It is also used as part of the common names of various similar species of loricariids. The superficially similar loach Beaufortia kweichowensis is also sometimes known as the "butterfly plec", despite not being closely related to the Loracariidae.
- Ancistrus, often incorrectly called "bristlenose pleco"