Two new species of Anaptychia (Physciaceae) from western North America, with notes on the other species of section Protoanaptychia.

Two new species belonging to the lichen genus Anaptychia are described from western North America. Anaptychia nevadensis is superficially similar to the Eurasian A. desertorum but is distinguished by having longer ascospores, in producing scant pruina only near the lobe tips, and in regularly producing variolaric acid. Anaptychia roemerioides is described to accommodate North American material which has previously been called A. ulotrichoides. It is macro-morphologically identical to the Asian species A. roemeri but differs in having longer ascospores and conidia. Both new species are strongly supported by phylogenetic analysis of ITS sequences. We also call attention to the existence of a further undescribed but possibly cryptic species within A. elbursiana. Variolaric acid is newly reported to occur occasionally in A. desertorum and A. elbursiana. A global key to the desert species of Anaptychia is provided. [ABSTRACT FROM AUTHOR]