Endococcus macrosporus
Anamorph: not known.
Teleomorph: stromata absent. Ascomata perithecia, 120-180 µm diam., scattered over the host thallus, globose, becoming erumpent through the host thallus, with a hardly papillate neck, ostiolate, black. Peridium carbonaceous, comprising 3-6 layers of radially compressed thick-walled dark brown angular cells. Interascal tissue absent, the ostiole lined internally with well-developed periphyses. Asci in a basal fascicle, forming in a gelatinized matrix, mature asci not seen so size is uncertain, thin-walled with a hardly thickened apex when young, presumably with rostrate dehiscence, not staining in iodine, 8-spored. Ascospores biseriately arranged, 18-20 x 6-7 µm, fusiform-ellipsoidal, the ends obtuse to acute, hardly constricted at the single ± median septum, dark brown, smooth- and thick-walled, without an epispore, gelatinous sheath or appendages.
Not assessed; rarely collected but probably overlooked.
On thalli of Rhizocarpon geographicum, apparently causing some minor degradation of the host as affected tissue is partly bleached.
Oceanic western and northern Scotland (VC98 Argyll, VC110 Outer Hebrides, VC112 Shetland), also VC4 N. Devon.