d Myriotrema album. e Ocellularia permaculata. f Redingeria glaucoglyphica. g Reimnitzia santensis. h Stegobolus radians The taxonomy of this clade will be dealt with in a separate paper (Rivas Plata et al. 2011b). Thelotremateae Rivas Plata, Lücking and Lumbsch, trib. nov. MycoBank 563413 Tribus novum ad Graphidoideae in Graphidaceae pertinens. Ascomata rotundata vel rare elongata, immersa vel sessilia. Excipulum hyalinum vel rare carbonisatum. Hamathecium non-amyoideum

learn more et asci non-amyloidei. Ascospori transversaliter septati vel muriformes, incolorati vel fusci, amyloidei vel non-amyloidei, lumina lenticulari vel rectangulari. Acidi lichenum variabili sed acidum sticticum et acidum norsticticum communi. Type: Thelotrema Ach. Ascomata rounded to rarely elongate, immersed to sessile. Excipulum hyaline to rarely carbonized, usually paraplectenchymatous. Periphysoids often present, sometimes with warty tips. Columellar structures

usually absent. Hamathecium and asci non-amyloid; paraphyses sometimes with warty tips. Ascospores transversely septate to muriform, colorless to (grey-)brown, amyloid to non-amyloid, septa thickened or reduced, lumina lens-shaped to rectangular. Secondary chemistry variable but stictic and norstictic acids predominant. Genera included see more in tribe (14): Acanthothecis Clem., Acanthotrema Frisch, Carbacanthographis Staiger and Kalb, Chapsa A. Massal., Chroodiscus (Müll. Arg.) Müll. Arg., Diploschistes Norman, Heiomasia Nelsen, Lücking and Rivas Plata, Leucodecton A. Massal.,

Melanotopelia Lumbsch and Mangold, Nadvornikia Tibell, Schizotrema Mangold Acyl CoA dehydrogenase and Lumbsch, Thelotrema Ach., Topeliopsis Kantvilas and Vězda, Wirthiotrema Rivas Plata, Kalb, Frisch and Lumbsch (Fig. 1). This clade includes over 300 currently IWR-1 order accepted species in 14 genera and is the morphologically most diverse and heterogeneous clade in the family (Fig. 8). It includes the unique genera Acanthothecis (lirellate ascomata with warty paraphyses), Diploschistes (on inorganic substrata with trebouxioid photobiont), Heiomasia (sterile with isidioid vegetative propagules), and Nadvornikia (mazaediate). The bulk of the clade corresponds to the genus Thelotrema sensu Hale (1980), now subdivided into several, partially unrelated linages (Thelotrema s.str., Acanthotrema, Chapsa, Chroodiscus, Schizotrema, Topeliopsis). Most of the currently delimited genera are well-supported as monophyletic, with the exception of Chapsa and Topeliopsis (unpubl. results, data not shown). The Nadvornikia lineage includes at least three non-mazaediate species previously classified as Myriotrema and Thelotrema by Hale (1980). Fig. 8 Selected species of Graphidoideae tribe Thelotremateae. a Acanthothecis subclavulifera. b Chapsa platycarpa. c Chroodiscus coccineus. d Diploschistes cinereocaesius. e Melanotopelia rugosa. f Nadvornikia hawaiiensis. g Thelotrema lepadinum.