La classe Parietarietea judaicae Oberd. 1977 in Italia.

The class Parietarietea judaicae Oberd. 1977 in Italy. On the basis of literature and unpublished data, a synthesis on the synanthropic chasmophilous perennial vegetation occurring in the Italian territories has been carried out. These plant communities are linked to masonry walls and rocky faces heavily disturbed by man, and are dominated by hemicryptophytes, chamaephytes and bryophytes. From the syntaxonomical point of view, in accordance with the majority of the authors who studied the matter, the wall vegetation should be ascribed to a well-distinguished class, Parietarietea judaicae Oberd. 1977, rather than to the Asplenietea trichomanis class, as proposed by other authors. Within the class, one order, Tortulo-Cymbalarietalia Segal 1969, and two alliances are represented in Italy: Parietarion judaicae Segal 1969 and Cymbalario-Asplenion Segal 1969. The first alliance, chiefly linked to the Mediterranean bioclimate, is mostly characterized by thermophilous chamaephytes, while cryptogams are nearly absent; the second one, distributed in the territories having a temperate bioclimate, is differentiated by an high abundance of small ferns and mosses. For each syntaxon the nomenclatural type and synonims are reported, as well as the indication of the main ecological, floristic and chorological characteristics. Besides, some unpublished relevés from NE-Sicily, Tuscany (Volterra) and Garda lake are presented, and a new association, Asplenio trichomanis-Umbilicetum horizontalis, is described