Two new corticolous species of Buellia (Physciaceae) from the Iberian Peninsula

Two corticolous species of Buellia, B. iberica and B. mediterranea are desc ribed as new to science from the Iberian Peninsula. Both taxa are widely di stributed in the study area. B. iberica occurs mainly at high altitudes in the mountains and B. mediterranea at low altitudes in coastal localities. T hey are closely related and characterized by their ascospores, which are in termediate between the Callispora- and the Buellia-type. In the study area, the new species have been erroneously reported as Buellia disciformis (Fr. ) Mudd, B. erubescens Arnold, B. chloroleuca Korb., B. sanguinolenta T. Sch auer and Rinodina ericina (Nyl.) Giralt. The main distinguishing features b etween these taxa and the new species are briefly commented and a key is in cluded. Habit photographs and illustrations of the ascospores of B. iberica and B. mediterranea are also provided.