Arthonia fuscopurpurea  

Thallus absent, lichenicolous.
Anamorph: conidiomata grouped in irregular locules in the outer edge of the ascomata, 25-40 μm diam., the wall red-brown, K+ dull brown. Conidiogenous cells lining the inner wall, doliiform to shortly cylindrical. Conidia 3.5-5 × 0.8-1 μm, bacilliform to ± cylindrical, often slightly curved, the ends rounded, aseptate, hyaline, thin- and smooth-walled.
Teleomorph: ascomata arthonioid apothecia, (0.2-) 0.5-1.5 (-2) mm diam., red-brown to brown-black, often surrounded by a ring of white, bleached host tissue, rounded, flat to convex, often with central part convex and surrounded by a flat, maculate zone of individual patches of developing hymenia and sometimes also conidiomata. Epithecium orange- to red- brown, K+ dull brown, sometimes with olive tinge. Hymenium 25-30 μm tall, pale brown-orange, K+ dull brown, I+ red. Hypothecium 40-100 μm tall, pale brown-orange, sometimes with red-brown mottling, K+ dull brown. Interascal tissue composed of short pseudoparaphyses 1.5-2.5(-3) μm diam., extending periclinally above the asci to form the epithecium in which the colourless apical walls are embedded in a pigmented matrix. Ascospores 9-15 × 3.5 μm, ovoid to cylindric-ovoid or clavate, 1-septate, the upper cell shorter and broader than the lower, hyaline, fairly thin-walled, with a narrow perispore that breaks up at maturity.
Chemistry: lichen products not known.