New localities of some Paulia species (Lichinaceae, Lichenized ascomycota) from Socotra (Indian Ocean)

New localities are reported for Paulia aldabrensis, P. myriocarpa, P: perforata, and P. schroederi, all being new to the lichen flora of Socotra (Yemen, Indian Ocean). The lichens have been found in shaded sites mainly on steep limestone rock surfaces. The new records of Paulia species from Socotra are included in. a discussion of distributional patterns in the genus. From the isolated and disjunctive distributions it is concluded that the Paulia species are palaeoendemics in arid to semi-arid tropical habitats with their origin on the Gondwana continent or evert earlier on the pre-Gondwana center of Pangaea.