Lichens from the Gypsum Park of the northern Apennines (N Italy)

203 infrageneric taxa, two of them of lichenicolous fungi, the others of lichenized fungi, are reported from an area with extensive gypsum outcrops in the northern Apennines (Gypsum Park, Provinces of Bologna and Ravenna, Northern Italy). 56 lichen taxa are new to the flora of the region. Five taxa are new to Italy: Acarospora placodiiformis, Acarospora nodulosa var. nodulosa, Lecanora subcarpinea, Lepraria crassissima v.isidiata, Psora saviczii. The lichen flora and vegetation of the survey area are compared with those known for the Iberian Peninsula and Morocco. The floristic and vegetational affinities are quite high, and the range of some gypsicolous species, such as Acarospora placodiiformis, A. nodulosa and Psora saviczii, are considerably enlarged by the North Italian findings. The main differences are: a) the absence in the survey area of some strictly gypsicolous species bound to a very arid climate, b) the presence of a set of common calcicolous and nitrophytic submediterranean lichens occurring on gypsum, c) the virtual absence of a true epilithic lichen vegetation on gypsum, most of the lichen stands being terricolous, d) the absence of acidophytic species growing on gypsum, e) the presence of a more mesic terricolous community dominated by Cladonia species, apparently scarcely developed in gypsum outcrops of Spain and Morocco. The epiphytic lichen flora and vegetation of the survey area has a typically submediterranean character. The more humid and rainy climate is most probably the main reason for the differences with the lichen flora and vegetation on gypsum of Spain and Morocco.