Contribution to the Knowledge of Rocky Plant Communities of the Southwest Iberian Peninsula

The rocky habitats of southern Portugal are ecosystems with extreme xericity conditions, associated special abiotic strains. In these unstable ecological a considerable diversity plant communities occurs. objective this study, carried out in the Algarve and Monchique, Mariánica Range biogeographical sectors, is to compare chasmo-chomophytic southwestern Iberian Peninsula, using phytosociological approach (Braun–Blanquet methodology) numerical analysis (hierarchical cluster analysis). From results, two new were identified, Sanguisorbo rupicolae-Dianthetum crassipedis Antirrhinetum onubensis, as result floristic differences from other associations already described within alliances Rumici indurati-Dianthion lusitani Calendulo lusitanicae-Antirrhinion linkiani, both included Phagnalo saxatilis-Rumicetea indurate class.