Buellia subericola, a new corticolous species characterized by a brown, blastidiate thallus without secondary chemistry and triseptate to occasionally submuriform ascospores, is described from the southern Iberian Peninsula. The species occurs on Quercus suber in grass-woodlands of cork-oak in the mesomediterranean belt with a warm mediterranean climate and oceanic influence. It is compared with other known Buellia s. lat. taxa which also reproduce asexually and have similar ascospores.

The study of the type and additional material of Buellia andicola, B. hypophana and B. reagens has shown that these taxa are conspecific with B. thiopoliza. Buellia thiopoliza is a muscicolous species growing at middle to high altitudes in the mountains of both hemispheres. It is easily recognized by its K+ purple-red yellow pigment mainly concentrated in the hypothecium, and by the presence of xanthones in the thallus and the apothecial tissues. The new combination Tetramelas thiopolizus is proposed. A key to all known Tetramelas species is included. The also muscicolous Buellia hypoleuca is reduced to synonymy with Phaeorrhiza sareptana var. sphaerocarpa.

Amandinea myrticola is described as new from Portugal. This corticolous species is characterized by the thin, smooth to minutely rugose and greyish thallus lacking secondary metabolites, the small lecideine apothecia which exhibit a pseudothalline margin when young and the small, smooth, Physconia-type ascospores with strongly pronounced and persistent median wall thickenings. It occurs on smooth bark in two localities characterized by a Mediterranean climate with an Atlantic influence.

We describe Calicium sequoiae as a new species of lichenized Ascomycota from north-western California, USA. The species is distinguished morphologically from other known members of Calicium by its stalks that react I+ blue, mature ascospores that are ornamented with spiral ridges, and apothecia that produce prominent white pruina. It is also the only Calicium known to produce thamnolic acid as a major secondary substance. Sequences from the ITS-region showed C. sequoiae to be unique among calicioid Physciaceae, and phylogenetic analysis positioned it close to C. adspersum, C. chlorosporum, C. lenticulare, Cyphelium notarisii, and C. tigillare. Thus far, Calicium sequoiae has been collected only from old-growth redwood (Sequoia sempervirens) forests, where it occurred on thick, fibrous bark of large redwood trees. A key to the 12 species of Calicium known from the Pacific Northwest is provided.