Revisión sintaxonómica a nivel de subalianza del orden Helianthemetalia guttati en la Península Ibérica e Islas Baleares

Using 840 releves extracted of the bibliography and multivariate statistical techniques (principal coordinate analysis and K-means), a review of the order Helianthemetalia guttati Br.-Bl. in Br.-Bl., Molinier & Wagner 1940 (=Tuberarietalia guttati) is fulfilled, in the area of Iberian Peninsula and Balearic islands. In this paper we propose a new combination (Sedion caespitosi (Rivas Martinez 1978) Perez Prieto & X. Font), we describe a new suballiance (Evacenion carpetanae Perez Prieto & X. Font, mesomediterranean grasslands commonly acting as a transition to supramediterranean grasslands) and one alliance is rejected (Sedion pedicellato-andegavensis). Resulting of this, the order is composed by four alliances: Molineriellion laevis, Thero-Airion, Sedion caespitosi and Helianthemion guttati. The last one is divided in two suballiances, Helianthemenion guttati and Evacenion carpetanae.