Closed mesophile grasslands, usually rich in Bromus erectus and orchids, of the periphery of the Mediterranean basin in Catalonia, the eastern Pyrenees, the Corbières, the Causses, Provence, the southwestern Alps and the northern Apennines. Many are comparatively dry and have sometimes been included in the Xerobromion.
Formations of the Causses; in the southern Causses they are mostly limited to the valleys where they occur at the base of slopes and, more rarely, on alluvial terraces; they also occupy the plateaux of the Causse de Sauveterre; the endemics Ophrys aveyronensis and O. aymonini find their optimal habitat in these communities ("Orchideto-Brometum").