Aggiornamenti e novità sulla distribuzione di Isoëtes gymnocarpa ed I. histrix (Lycopodiophytina) in Toscana

The occurrence in Tuscany of I. gymnocarpa (Gennari) Braun is here confirmed. This recently re-evaluated species was documented up to now only for Sardinia, Sicily and Calabria. Besides the historically quoted localities for southern Tuscany (under the name I. histrix Bory f. subinermis Durieu), this species occurs in several localities in the Elba Isle and in Valle delle Rozze (San Vincenzo, Livorno). Moreover, this species occurred in historical times also in the Isle of Capraia, Promontorio di Piombino and Castagnolo (Pisa). On the contrary, the occurrence of I. histrix is confirmed for Tuscan Archipelago (Isola di Capraia and Isola d'Elba), where the species was not observed since more than 100 years.