Anamorph: not known.
Teleomorph: stromata absent. Ascomata perithecia, 500-650 µm diam., ± globose with a short papillate neck, scattered or in small clusters, deeply immersed within the substratum with the neck hardly protruding. Peridium black in external view, quite thin, coriaceous, composed of an outer layer of irregular dark brown thick-walled globose cells and an inner layer of thinner- and paler-walled cells, covered in irregular dark brown thick-walled branched hyphae. Interascal tissue apparently absent at maturity, perhaps evanescent. Asci 85-110 x 17-22 µm, clavate (dependent on ascospore arrangement), with a fairly long gradually tapering stalk, thin-walled, not fissitunicate, the apex obtuse to truncate with an inconspicuous apical ring 3-4 µm diam. and ca 1 µm thick that does not blue in iodine, 8-spored. Ascospores arranged irregularly, (23.5-) 26-29 x 7-8.5 µm, cylindric-ellipsoidal to narrowly fabiform, straight or slightly curved, dark smoky brown when mature, fairly thick-walled, smooth, mostly aseptate but with a few spores with ± median to slightly submedian septa and very occasionally with a minute rather flattened hyaline basal appendage, without a gelatinous sheath.
Not formally assessed. Only known from a single rather sparse collection, but the species is very inconspicuous and may well be overlooked.
The species is distinguished from other species of Barrmaelia by its large, usually aseptate ascospores.Occasional ascospores appear to become septate; the significance of this is not known.
Found in very rotten wood, almost certainly of Quercus petraea.
Known from a single locality in VC2 E Cornwall.
Presumably a saprotroph, though there is no experimental evidence.