Isomira hypocrita can reach a body length of about. These rather large comb-clawed beetles have a quite strong and silkyshinyblack body, with elongated, almost oval elytra. Pronotum and elytra are strongly but finely dotted, with flat interspaces of the wrinkles. Hairiness of the back is short, fine and not very dense. Antennae, legs and mouth are yellow-brown to brown. Also the elytra may be yellow-brown.