Tichodroma

Tichodroma is the only known genus in the family Tichodromidae. The wallcreeper (Tichodroma muraria) is the only extant species, but the extinct Tichodroma capeki is known from the Late Miocene of Polgardi, Hungary. Initially, Linnaeus placed the wallcreeper in the family Certhiidae, along with the treecreepers, while other authorities have placed it the nuthatch family Sittidae, as its own subfamily. A 2016 phylogenetic study of members in the superfamily Certhioidea suggests it is a sister of the Sittidae.