Sagediopsis lomnitzensis
Anamorph: not known.
Teleomorph: ascomata perithecia, scattered or loosely clustered, immersed in the host thallus or hymeniurn, the exposed part level with the thallus surface or slightly projecting, black, flat or slightly convex, 60-90 (-110) µm diam., the ostiole visible as a small depression; in section perithecia 150-215 µm diam., the wall ± colourless below and strongly melanized in the ostiolar region, with an outer layer of dark brown thick-walled vertically elongate cells and an inner layer of thin-walled flattened tissue. Interascal tissue not seen (sparse branched and anastomosed filaments present mainly at the sides of the hymenium fide Orange 2002). Periphyses always present, colourless within and with the surrounding peridial cells hyphal in construction, dark brown. Asci 40-50 x 17-20 µm, clavate to saccate, short-stalked, thick-walled and fissitunicate with rostrate dehisence, the apex rounded, 8-spored. Ascospores 15-16.5 x 5-5.8 µm [(9.5-)11-18 x 5-7 (-8) µm fide Orange 2002], ellipsoidal to fusiform-ellipsoidal, colourless, hardly constricted at the single ± median septum, thin-walled, smooth, with a perispore (usually not visible within the ascus) that swells significantly in KOH after release.
Description adapted in part from Orange (2002).
Listed as of Least Concern but Nationally Rare by Woods & Coppins (2012).
In thalli and apothecial margins of Ionaspis lacustris and I. odora, often causing little or no visible damage.
Throughout western and northern Britain in suitable habitats.