Thallus white or pale greyish, often cracked, not corticate and appearing slightly floury.
Anamorph: conidiomata pycnidia, 200-580 µm diam. and 200-600 µm high, with a globose base tapering into a narrow conical neck, black, thick-walled and carbonaceous. Conidiogenous cells ca 5 µm long and 3-3.5 µm diam., doliiform, probably proliferating percurrently. Conidia 5.5-6.5 × 2.5-3 µm, pyriform-ellipsoidal, the base truncate, hyaline, aseptate, sometimes extruded as a tendril. Microconidia not detected.
Teleomorph: Ascomata perithecia, 280-350 µm diam., shallowly domed, ± globose, the ostiole not very conspicuous, black and carbonaceous. Interascal tissue of copious fairly thick-walled pseudoparaphyses ca 1.5 µm diam., branching not conspicuous. Asci 100 x 11.5µm, cylindrical, the base short and gradually tapering, the apex rounded, thick-walled and fissitunicate with a conspicuous broad ocular chamber, 8-spored. Ascospores arranged uniseriately, 12.5-13 x 6.5-7.5 µm, ellipsoidal to pyriform, the apex rounded and the base obtuse, slightly constricted at the slightly submedian septum, hyaline, rather thick-walled, smooth, without an epispore or gelatinous sheath.
Assessed by Woods & Coppins (2012) as of Least Concern, but listed as Nationally Scarce.
Similar in teleomorphic characters to Anisomeridium biforme, but with conical rather than ± globose pycnidia and somewhat larger conidia.
Throughout western Britain, and southern Britain east to Hampshire.
On bark of various trees including Acer, Quercus and Ulmus, in old woodland and parkland.