Thallus composed of minute fan-shaped, squamulose or coralloid structures, bright green when wet, pale brown-green when dry, also with elongated finger-like projections 15–150 µm in length, formed by groups of 4–6 goniocysts surrounded by hyaline, thin-walled, gelatinized cortical cells without papillae. Prothallus absent. Photobiont chlorococcoid, cells subspherical to globose, 8–12 µm diam.
Anamorph: not known.
Teleomorph: Ascomata perithecial, at first globose, sometimes becoming ovoid to pyriform, 150–250 µm diam., superficial or partially immersed between squamules, pale brown at first, dull grey-brown when mature, surface matt and smooth. Involucrellum absent. Ostiole appearing pale externally, 30–50 µm diam. Excipulum 30–40 µm thick, 3-layered. Subhymenium plane to concave, pale, to 10 µm thick. Interascal tissue of short periphyses, 6–12 × 2 µm; hymenial gel J+ blue. Asci 8-spored, 15–35 × 60–90 µm, clavate, fissitunicate, J−. Ascospores cylindrical to ellipsoidal, (23–) 30 (−35) × (11−) 14 (−15) µm, hyaline, muriform, fewer than 20 cells visible in optical section.
Not formally evaluated, but the species was listed as Nationally Rare by Woods & Coppins (2012). It is confined to ancient woodlands and is likely to be threatened.
Currently reported from VC3 S Devon, VC11 S Hampshire, VC36 Herefordshire and VC48 Merioneth. Also reported from the Czech Republic and Germany.
On trunks of mature Quercus petraea and Q. robur in woodland, associated with Isothecium myosuroides, Normandina pulchella and Cladonia sp.