Coenological research on macrofungi in evergreen oak woods in the hills near Siena (Italy)

For a mycocoenological study of macromycetes in Mediterranean evergreen forests in the Sienese pro- vince, five stands belonging to the Quercion ilicis have been observed during more than two years. The phytosociological analysis of these evergreen oak woods, situated at the limit of the geographical distribution of the alliance, reveals them as intermediate between the typical Mediterranean vegetation and the sub-Mediterranean deciduous broad-leaved forests. 181 fungal species were recognized and assigned to seven ecological groups on the basis of substratum, habitat, forest management and/or particular mycorrhizal relationship. Our results have been compared with those obtained in some European deciduous forests. Such a comparison shows the occurrence of 16 thermophilous fungal species in the Siena woods which are missing or very rare in the European deciduous forests. On the basis of our present knowledge, five of these species ( Boletus lepidus, Hygrophorus dichrous, Hygrocybe nigrescens, lnocybe similis, Phellinus torulosus) may be considered as strictly tied to the evergreen oak woods. Five others, which have been reported for several European phytocoenoses, seem to be 'preferential taxa' of our evergreen oak woods, namely: Cortinarius calochrous, C. sodagnitus, Hygrophorus arbustivus, H. russula, Lyophyllum immundum. On the whole the highest similarities have been found with the more xerothermophilous European forests (Querco-Lithos- permetum and Sorbo-Quercetum). The presence in the Quercus ilex woods of numerous more mesophilous fungi, some of which are widespread in beech forests, underlines the transitional nature of the phytocoenoses studied.