The key to identifying thyme (Thymus L., Lamiaceae) in the middle zone of the European part of Russia

In the flora of the middle zone of the European part of Russia (within the boundaries of «Flora...» by P. F. Mayevsky, 11th edition) from the genus Thymus L. (Lamiaceae), 19 species are reliably known: section Goniothymus – T. chamaedrys; section Verticillati – T. dimorphus, T. marschallianus, T. pseudopannonicus, T. stepposus, T. tschernjaievii; section Serpyllum – T. pseudocretaceus, T. serpyllum; section Kotschyani – T. zheguliensis; Subbracteati section – T. calcareus, T. cretaceus, T. dubjansky, T. kelleri, T. kondratjukii, T. pallasianus; section Margidromi – T. goginae, T. oblongifolius, T. lyubovae (prov.), T. tzvelevii. Previously cited for the forest-steppe zone of the Volga region, T. cimicinus Blum ex Ledeb. s.str. are excluded from the flora of the region, T. loevyanus Opiz and T. pulegiodes L. s.str. are excluded from the flora of Russia.