Tichodroma is the only known genus in the family Tichodromidae. Initially, Linnaeus placed Tichodroma in the family Certhiidae, along with the treecreepers.,[1] 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.[2]
The wallcreeper (Tichodroma muraria) is the only extant species, but the extinct Tichodroma capeki is known from the Late Miocene of Polgardi, Hungary.[3]