Exomorfología y anatomía de órganos vegetativos aéreos en especies de Flourensia DC. (Asteraceae) con importancia fitoquímica

the genus flourensia dc. is american and comprises 32 species. they are resiniferous shrubs used in folk medicine. as they have potential economic value, its chemical compounds have been characterized and some possible uses identified. in this work, the exomorphology and anatomy of vegetative organs of f. hirta s. f. blake, f. leptopoda s. f. blake, f. niederleinii s. f. blake and f. tortuosa griseb., endemic species from central argentina, have been studied. all species are similar in leaf and stem anatomy. regarding the epidermis, it is possible to differentiate the species according to the stomatal frequency and the presence of trichomes. finally, the most remarkable differences were found in leaf exomorphology, since there was a large variation in shape and size of blades and petioles. concerning the secretory structures, trichomes and secretory ducts were found in the leaves and stems of all species, which would be responsible for the production and secretion of the resins.