Article

The flora of the catchment basin of Rio Santa Lucia (S. W. Sardinia) has been studied, 669 taxa, 628 of which were species, 35 subspecies, 2 varieties and 4 hybrids were found. They were included in 364 genera and 101 families. The floristic richness indices have been determined and compared with those of other studied areas of Sulcis. An analysis of the biological spectrum showed the therophytes at 41.2 % in confirmation of the full Mediterranean character of the area and the phanerophytes at 10%, showing the high degree of wooded cover. A comparison with the biological spectra of other floras shows similar values, except for a lower value for the therophytes and a significantly higher value (2.7%) for the hydrophytes. The chorologic spectrum shows dominance of Mediterranean elements (71.6%), particularly steno-Mediterranean (26%) and euri-Mediterranean (21.8%). The westemMediterranean (3 .5%), the southem-Mediterranean (3.5%) and the Atlantic-Mediterranean (3.1 %) components are important in identifying the biogeographic barycentre of the studied area. The contingent of endemics (60 taxa) was 9% and shows the dominance of SardinianCorsican (31.7%) and Sardinian (21.7%) elements, that together make up 53.4% of the total. IO new entities, which are endemic or with a particular phytogeografic interst for the mountain complex of Sulcis, have been lastly reported.