Varanopidae is an extinct family of synapsid "pelycosaurs" that resembled monitor lizards and might have had the same lifestyle, hence their name. Like many other pelycosaur families, they evolved from an Archaeothyris-like synapsid in the Late Carboniferous; they had become extinct by the end of the Middle Permian. A varanopid from the latest Middle Permian Pristerognathus Assemblage Zone is the youngest known varanopid and the last member of the "pelycosaur" group of synapsids.