Apothecia sessile or slightly elevated, mostly in the centre; disc at first concave, afterwards nearly plane, dark chestnut-coloured, surrounded by a naked or isidiiferous, indexed, thallodal margin; asci elongato-subventricose, 8 spored; spores elliptical, unilocular, hyaline; .002 in. long, by .00125 in. broad.
Source: wiktionary