Article

The vascular flora of MI. Cetona, an isolated calcareous massif in SE Tuscany stili unexplored from the geobotanical viewpoint, is fully reported. The flora includes 650 native species distribùted in 422 genera and 91 families. New records for the flora of Tuscany are: Silene catholica, Sternbergia colchicijlora, Valeriana tuberosa, Ornithogalum divergens, Thymus pannonicus and, possibly, Linum austriacum subsp. tommasinii. Old records of rare plants are al so eonfimed for the regional flora. In respect of the close MI. Amiata, the flora of MI. Cetona is much richer, but, at the same time, it is not as rich as other eomparable Apenninic areas. The life-form speetrum highlights an Hemieryptophytes/Terophytes ratio of 2.2 that refleets a submontane, sllboceanie bioelimate. Chamaephytes are well represented , eonsistently with the roeky, barren nature of the massif. Aiso geophytes are somewhat abundant, possibly because of the coexistenee of xerie geophytes of stony pastures with mesie geophytes of nemoral habitats. From the ehorologieal viewpoint, the MI. Cetona flora is charaeterized by a relatively low proportion of boreal species and by a marked ineidence of the Oromediten'anean element. Owing to the presence of severa I apenninie endemie speeies it is to be included in the Apenninie sector of the oroipsophytie dominion of the European subregion. In partieular, this flora has phytogeographieallinkages with the centrai Apennines, of whieh it appears as a northem isolated appendix harbouring a number of speeies towards their northem distribution limit. This affinity is eonfimled by the presenee of several rare species with a distribution baryeentre in the Balkans. The phytogeographieal distinctiveness and the good eonservation status of the Cetona flora suggest the institution of a nature reserve aiming at protecting it against future changes.