Graphidaceae of Central French Guiana

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Graphis turgidula Müll-Arg B 25432

Thallus thin, epiphloeodal, corticolous, closely appressed to the substrate, corticate and shining, pale greenish gray, quite uneven due to overgrowing other lichens and rough bark (apparently not due to large thickenings of thallus), K+ orange-red, P+ yellow. Apothecia dense, clustered densely, with prominent thalline rim, rim exceeding exposed excipular labia, these forming a deep and rather wide cleft, but convergent at inner tips, not striate, disk closed. Ascomata appearing strongly cleft, not to rather constricted below, sessile and not branching, 1-2 mm long by .3-.4 mm wide (including thalline margin), slightly and consistently curving; hymenium plane below, hypohymenium pallid, epihymenium colorless and sparse, not inspersed. Paraphyses capilliform eseptate, spores 20-24 locular, 14x8-100µ, 2-4/ascus. Norstictic acid.

This appears to be the norstictic variety of G. turgidula.