The Tanner Beetle (Prionus coriarius) is a species of longhorn beetle in the Cerambycidae family.
This is one of Britain's largest beetles, reaching almost 4cm in length, with the females being larger than the males. This species is dark red-brown, with a darker head and thorax, and the elytra gets lighter away from the thorax. For a longhorn beetle, this species has relatively short antennae. This species is scarce in Britain, with a scattered population in southern Britain. They are found in decidous woodland, and are quite common in the New Forest.