LECANORA SECTION PLACODIUM (LICHENIZED ASCOMYCOTINA) IN NORTH-AMERICA- NEW TAXA IN THE L-GAROVAGLII GROUP

The Lecanora garovaglii group (subg. Placodium sect. Placodium) typica lly has inflated, sinuous and plicate lobes, and the upper cortex lack s distinct conical bundles of hyphae. The L. garovaglii complex itself centered around L. garovaglii (Korber) Zahlbr. (syn. L. peruviana (Mu ll. Arg.) Zahlbr.), includes material first described as L. cascadensi s Magnusson (syn. L. nevadensis Magnusson), which differs mainly by di sc colors and epihymenial characters often modified by light condition s and parasitism. As treated in this article, L. garovaglii s.l. also includes several overlapping cortical chemotypes. A second complex cen ters around two new species (previously misidentified as L. cascadensi s or other taxa). Lecanora sierrae Ryan & Nash, found mainly at high e levations in California, and Lecanora pseudomellea Ryan, found mainly at intermediate elevations in the Northwest, are new species, treated broadly to include a typical medullary chemotype (fatty acids only) bu t also chemotypes containing in addition either pannarin or psoromic a cid.