Thallus immersed; photobiont in scattered groups or absent. Anamorph: conidiomata pycnidia, often present, similar in form to the ascomata and only slightly smaller. Conidiophores in a palisade lining the inner surface of the conidiomatal wall, short, aseptate, bearing 2-3 conidiogenous cells. Conidiogenous cells 6-9 x ca 2 µm, ± cylindrical or gradually tapering, proliferating percurrently. Conidia 2.5-3 x 1-1.5 µm, bacillar, aseptate, hyaline, smooth- and thin-walled. Ascomata 100-170 (-240) µm diam., usually entirely immersed in pits in the substratum, occasionally emerging; involucrellum lid-like, flat to slightly convex, scarcely spreading, with a broad ostiole. Ascomatal wall pale brown, thin. Interascal tissue composed of fairly thick-walled branched and anastomosing pseudoparaphyses 1.5-2 µm diam. Asci 55-65 x 13-15 µm, clavate, short-stalked, thick-walled and fissitunicate with an extendible inner wall, 8-spored. Ascospores arranged biseriately, 15-17.5 x 4-5.5 µm [14-21 × 5-9 μm fide Coppins & Orange 2009], clavate to clavate-ellipsoidal, 1-septate with a slightly supramedian septum, hyaline, thin-walled, smooth, with a gelatinous sheath ca 1 µm thick.