A world-wide key to the thelotremoid Graphidaceae, excluding the Ocellularia-Myriotrema-Stegobolus clade

In the course of an ongoing systematic and taxonomic revision of the lichen family Graphidaceae (including Thelotiemataceae), we present world-wide keys to the currently accepted thelotremoid geneia and species, excluding the columellate taxa and their relatives of the Ocellularia-Myriotrema-Stegobolus clade (Melanotrema, Myriotrema, Ocellularia, Ocellularia clandestina group, Redingeria, Stegobolus), which will be treated in I forthcoming paper The keys include all genera and species with chroodiscoid, lepadinoid, and topeliopsidoid apothecia and other taxa featuring periphysoids or fibrils, and their relatives Taxa keyed out to genus and species level are Acanthotrema, Chapsa, Chroodiscus, Diploschistes. Fibrillithecis, Gyrotrema, Leptotrema, Leucodecton, Melanotopcha, the 'Ocellularia' cruentata group, Pseudoramonia, Reminitzia,Schizotiema, Thelotrema, Topeliopsis and Wirthiotrema Over 260 species are treated, including a few yet unnamed taxa. The following taxonomic and nomenclatural novelties are introduced Acanthonema frischu Lucking sp nov, Chapsa a., aggregata (Hale) Sipman & Lucking comb nov, C albida (Nyl) Lucking & Sipman comb nov, C albomaculata (Sipman) Sipman & Lucking comb nov, C boninebsis (Tat Matsumoto) Rivas Plara & Mangold comb nov, C elabens (Mull Arg) Rivas Plata & Mangold comb nov, C imperfacta (Hale) Rivas Plata & Lucking comb nov., C laceratula (Mull Arg) Rivas Plata & Lucking comb nov, C maginfica (Berk & Broome) Rivas Plata & Lucking comb nov, C. meghalayensis (Patw & Nagarkar) Lumbsch & Divakar comb nov, C meridensis (Kalb & Frisch) Lucking, Lumbsch & Rivas Plata comb nov, C nurabilis (Zahlbr) Lucking comb nov. C neet (Hale) Mangold & Lucking comb nov, C paralbida (Riddle) Rivas Plata & Lucking comb. nov, C pseudoexanihismoccapa (Patw & C R Kulk) Rivas Plata & Lucking comb nov, C pulvereodisca (Hale) Rivas Plata & Mangold comb nov, C scabiomarginata (Hale) Rivas Plata & Lucking comb nov, C waasu (Hale) Sipman & Lucking comb nov, Fibrillithectis argentea (Mull Arg) Rivas Plata & Lucking comb nov, F carneodisca (Hale) Rivas Plata & Lucking comb nov, F confusa Lucking, Kalb & Rivas Plata spec nov, F diminta (Hale) Rivas Plata & Lucking comb nov, b exinna (R C Harris) Rivas Plata & Lucking comb nov, F fissurara (Nagarkar & Hale) Rivas Plata & Lucking comb nov, F gibbosa (H Magn) Rivas Plata & Lucking comb nov, Leucodecton desquanniescens (Vain) Lucking comb nov, L oxysporum (Redinger) Lucking comb nov, Schizotrema cryptotrema (Nyl) Rivas Plata & Mangold comb nov, Thelotrema patwardhann (Hale) Rivas Plata & Mangold comb nov, Topchopsis guaiquinimae (Sipman) Rivas Plata & Mangold comb nov, and T tuberculifera (Vain) Rivas Plata & Mangold comb nov. Using the examples of Fibrillithecis halei's lat, Leucodecton compunctellum s lat, and Thelotrenta monosporum s lat, we show how difficult species complexes can be flexibly treated in a key, allowing for either a broad concept or the distinction of several individual taxa.