Protoclaviger is an extinct Early Eocene transitional fossil myrmecophile of the rove beetle subfamily Pselaphinae, and a stem group of the modern supertribe Clavigeritae, of which Claviger is a representative. All modern Clavigeritae are morphologically specialized obligate colony parasites of ant nests, soliciting food via trophallaxis from worker ants, and preying on the nest brood.