Article

This research has been carri ed out to provide an evaluation ofthe bryophyte diversity ofSicilian urban areas. For this purpose, the bryophyte flora of the coastal towns of Agrigento and Siracusa (S and SE Sicily, respectively) was studied. These data has been analysed together with those of the towns of Enna (C Sicily), Catania (E Sicily) and Palermo (N Sicily), published previously. The bryophyte flora of Sicilian urban areas has also been compared to other Italian and Spanish ones. A database with chorological, ecological and biological data has been set up and a cluster analysis has been carri ed out. The results show that the urban bryoflora is rich and diversified in Sicily. Besides a high number of taxa, it is characterized by a high number of urbaniphilous taxa, a higher value of hepatics/mosses ratio, and, from a chorological point of view, by lower and higher incidence of temperate and oceanic-Mediterranean taxa respectively, than that of the other considered cities. Although the presence of green areas and of poorly disturbed habitats greatly affects species diversity, geographical and climatic factors mainly influence bryoflora composition and richnesso