La flora vascolare del Lazio.

The vascular flora of Lazio (Central Italy) - The long and meticulous data raising on the vascular flora of Lazio region, started by Giuseppe Lusina, then carried on by Bruno Anzalone and finally inherited by Edda Lattanzi and Mauro Iberite, represents a first working phase lasted 60 years and is briefly introduced in this paper. The vascular flora of Lazio region currently consists of 3330 units and 3146 species, divided into 150 families and 896 genera. For each unit the following information is provided: synonym(s), commonness in the regional territory, IUCN threatening status, geographical areas in which it occurs, ideal altitude range and habitat. Since the publication of the latest regional checklist (1996-98), the total amount of units increased from 3185 to 3330 (+4.46%); this is mainly due to the substantial and lively contribution of floristic and taxonomic studies provided both by researchers and by amateurs. Due to the complex geological and environmental patch as well as to the geographical position of Lazio region, this flora is to be considered one of the richest in Italy. Finally, a summarizing outline is given of the priority vascular plants of the region: 1) very rare units, 2) possibly extinct units, 3) threatened units, 4) units uniquely occurring in Lazio region, 5) non-native units; an outline that can serve as an up-to-date scientific tool in managing the floristic heritage of Lazio region.