Teucrium andrusi, described by Post from Mardin province, Turkey, was synonimized with T. paederotoides in the flora of Turkey. According to the records in the flora of Turkey T. paederotoides was a steno-endemic species, only known from the type locality in Gaziantep and from Mardin province. Specimens of T. paederotoides s.l. were collected from both localities and a detailed comparison of the plants from Gaziantep with those from Mardin revealed that the two populations were sufficiently distinct from each other to be recognised as separate species. Thus, T. andrusi Post is reinstated from the synonymy with T. paederotoides. Teucrium andrusi is morphologically different from T. paederotoides s.s. in terms of its general indumentum, leaf margin, bract and calyx shape, corolla colour and nutlet macro-micromorphology. It can be anatomically distinguished from T. paederotoides s.s. by stoma type, stomatal distribution on the leaf surface, crystal content in the cells and cuticula thickness. Ecological data related with the accompanying species also support species status for T. andrusi. While the two taxa are very similar in pollen and nutlet morphology, trichome density on the nutlets are different. © 2011 The Authors.