Thallus yellowish-olive to pale yellow-grey or fawnish, in irregular patches or bands, 2-8(-12) cm diam., smooth, waxy, continuous, rarely irregularly cracked, matt or shining, often with minute, scattered, white spots (×10 lens), corticolous. Perithecia ± immersed to emergent, in scattered, rounded to irregular verrucae, 1-3 mm diam., flattened to slightly swollen, subhemispherical, often ± covered with cortex and bark cells and appearing ± frosted, eventually black and shining, 1-4 perithecia in a stroma, involucrellum 10-60 µm thick, black carbonaceous, exciple brownish-yellow, 10-25 µm thick. Ostiole apical, 0.1 mm diam., flat, subpunctate or slightly raised, yellow-brown or reddish to black, occasionally whitish-grey, often open to interior or perithecial cavity. Ascospores broadly ellipsoid or oblong with pointed ends, muriform, 7-11 transverse septa and with 2-5 locules per tier, 60-70 × 30-35 µm, wall 1.5-2 µm thick.