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In Umbilicaria hirsuta and U. grisea the so-called soredia originate from structured plectenchyma of the upper thallus layer (thus contrasting with true soredia, which are pushed off from unstructured medullar plectenchyma), and, therefore, are termed parasoredia. Both species have been regarded to comprise (in western Europe) forms with relatively large thalli and a pale lower surface; rhizinomorphs may be present (with varying density) or absent; propagation is not by parasoredia, but by flattened diaspores (schizidia s. l.) These forms are united here and described as a separate species: U. freyi (syn. U. hirsuta var. pyrenaica Frey and U. grisea resp. murina f. subpapyria Frey). So far, the species is known to occur from the western Alps through C. France to the Pyrenees, C. Spain and Italy including Sardinia. [ABSTRACT FROM AUTHOR]