What is "varanopidae"

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.