Segregated from the genus Odontites (Scrophulariaceae, Rhinanthoideae) in its traditional, large sense, the four small genera Macrosyringion (with two species from Spain and S Balkans/Asia minor respectively), Odontitella (with one species from the Iberian Peninsula), Bornmuellerantha (with one species from Asia minor) and Bartsiella (with one species from Morocco) are recognized; of these, Bartsiella is described as genus new to science, based on Odontites rameauanus. Odontites s. str. is a natural but morphologically manifold taxon, which is characterized by its unique microreticulate pollen surface, representing an autapomorphy within the Rhinantheae. The genus is of W Mediterranean origin and comprises, in its revised circumscription, 26 species with 21 subspecies, which are mostly stenochoric endemics restricted to single islands or mountain massifs; only three species are widespread, their areas extending over several floristic regions: O. viscosus (from Morocco northeastwards to the Swiss Valais), O. luteus (Submediterranean-Central European-Pontic) and the Red Bartsia O. vernus (Eurasiatic). A taxonomic revision of the five genera is presented, including a general treatise of morphological and biological features, keys, synonymies, descriptions, distribution maps, notes on infraspecific variation, and illustrations of the species. Odontites citrinus from Tunisia is described as a species, O. viscosus subsp. lusitanicus as a subspecies new to science, and 10 names, i. e. Bartsiella rameauana, Odontites hispidulus, O. vulgaris subsp. mesatlanticus, O. vulgaris subsp. siculus, O. vulgaris subsp. himalayicus, O. linkii subsp. cyprius, O. maroccanus O. discolor subsp. ciliatus, O. squarrosus, and O. squarrosus subsp. foliosus, are formed as combinations new to science.