Six new species of Graphidaceae from Sri Lanka

Six new species of Graphidaceae are described from Sri Lanka, four in Graphis sensu Staiger and one each in Fissurina and Thelotrema. Fissurina srilankensis Weerakoon, Wijeyaratne & Lücking is characterized by lirellae with well-developed labia and comparatively large, muriform ascospores. Graphis allugallenensis Weerakoon, Wijeyaratne & Lücking is similar to G. vittata but has a distinctly verrucose thalline margin along the lirellae. Graphis dotalugalensis Weerakoon, Wijeyaratne & Rivas Plata resembles G. proserpens in the exposed lirellae with striate labia and apically carbonized excipulum but differs in the comparatively large ascospores. Graphis knucklensis Weerakoon, Wijeyaratne & Wolseley features lirellae with striate labia, an inspersed hymenium, and norstictic acid as secondary compound. Graphis srilankensis Weerakoon, Wijeyaratne & Lumbsch has entire labia with a completely carbonized excipulum, inspersed hymenium, transversely septate ascospores, and produces norstictic acid. Finally, Thelotrema pseudosimilans Weerakoon, Wijeyaratne & Lumbsch is close to T. similans in the corticate thallus and prominent apothecia with narrow pore, but has consistently larger ascospores.