Trans. Br. Mycol. Soc. 85(4): 699-707, 1985

Ascomata 700-1000 mm high, 850-1200 mm wide, 245-315 mm thick, subglobose in frontal view, fusiform in sagittal section, laterally compressed, completely or three-fourths immersed in a black stroma, with a longitudinal furrow at the top, ostiolate, carbonaceous to coriaceous, black, gregarious, often close together.

Peridium two-layered; outer layer clypeiod near the ostiole, composed of elongate more or less irregular cells encrusted with melanin particles, interspersed with cells of the host; inner layer is composed of smaller, hyaline cells. Ostiole 50-70 mm diam., depressed or slightly projecting, in the centre of the apical furrow, circular; ostiolar canal subglobose, filled with a network of branched or forked septate periphyses. Pseudoparaphyses trabeculate, unbranched at the base becoming branched and anastomosing above the asci, merging with the periphyses in the ostiolar canal, embedded in a gelatinous matrix.

Asci 325-440 x 29-37 mm, 8-spored, cylindrical, thick-walled, pedunculate, fissitunicate, with a refractive apical plate in the ectoascus and a refractive apical plate in the endoascus, not bluing in IKI.

Ascospores 45-60 x 16-23 mm, biseriate, ellipsoidal to broadly fusiform, muriform, with (9-) 10-11 (-12) transverse septa and 1-3 longitudinal septa in all but the end cells, slightly constricted at the septa, yellow-brown except for hyaline to light brown apical cells, glabrous with a gelatinous cap around apical and subapical cells.