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 Add this item to the list   563413 Original description
   
Remarks (public):This clade includes over 300 currently accepted species in 14 genera and is the morphologically most diverse and heterogeneous clade in the family. It includes the unique genera Acanthothecis (lirellate ascomata with warty paraphyses), Diploschistes (on anorganic 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). Tribe Thelotremateae can be divided into three supported clades: one including the core genera Chapsa, Chroodiscus, Leucodecton, and Thelotrema; a second one including the genera Acanthotrema and Diploschistes, and a third, very heterogeneous clade including the remaining genera, all small and with disparate morphology. 
Description type:Original description 
Description:Ascomata rounded to rarely elongate, immersed to sessile. Excipulum hyaline to rarely carbonized, usually paraplectenchymatous. Periphysoids often present, sometimes with warty tips. Columella 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. 
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