Floristic and phytosociological studies undertaken in six areas of the state of Pernambuco were selected with the aim of analyzing the Relative Importance of the woody medicinal plant species of Pernambuco's caatinga from an ethnobotanical perspective. For the data analysis, only those identified up to the species level were selected and information on medicinal properties was obtained for each one from the literature. The Relative Importance was calculated for each species. From the 57 woody species, 22 had therapeutic indications; from these, Anacardium occidentale L., Tabebuia impetiginosa (Mart. ex DC) Standley, Schinopsis brasiliensis Engl., and Myracrodruon urundeuva (Engl.) Fr. All. had the greatest values of Relative Importance. The correlation analysis made clear that the Relative Importance of the species is negatively correlated with the Density and Relative Frequency (p<0.05). The most important species, in the ethnobotanical point view, are the most vulnerable, possible due to the systematic exploration they have been suffering. Schinopsis brasiliensis and Myracrodruon urundeuva are listed as endangered species and deserve special attention in the development of techniques of sustainable management, where both economic return and species conservation must be guaranteed. In depth studies that take into consideration each region's characteristics are necessary both from a floristic perspective and considering medicinal aspects, since each area seems to have its own woody medicinal flora, as suggested in the cluster analysis.
Tropical dry forests; medicinal plants; ethnobotany; floristic; phytosociology
