Anamorph: not known.
Teleomorph: ascostromata perithecial, 220-300 µm diam. and 250-370 µm high, in clusters of 6-15, initially immersed just beneath the ectostroma surface of the host fungus but sometimes becoming almost superficial as the host tissue degrades, the basal part ± globose with a shortly papillate to pyriform neck 70-100 µm diam., black, smooth-walled. Peridium 30-40 µm thick, consisting of several layers of brown cells 6-10 x 3-5 µm in size, the cells of the neck region tending to be smaller and more strongly melanized. Interascal tissue composed of copious trabeculate pseudoparaphyses ca 1 µm diam., the ostiole lined with periphyses. Asci 80-95 x 9-12 µm, narrowly clavate with a long tapering stalk, the apex rounded, thick-walled and fissitunicate with a clear ocular chamber, 8-spored. Ascospores biseriately arranged, 16.5-20 (-24) x 4.5-6 µm, fusiform, the apex acute and the base obtuse, straight or somewhat inaequilateral, strongly constricted at the ± median primary septum, usually but tardily developing a secondary septum in each cell, the cell above the primary septum strongly inflated, hyaline, smooth-walled, apparently without a gelatinous sheath or appendages.
Not formally assessed. Currently, only known from five sites in GB&I, but the species is inconspicuous and may be overlooked.
Distinguished from Pseudotrichia mutabilis most easily by the ascospore size, possibly also fungus host preference.
In GB&I, in rotten wood of Quercus and Fraxinus spp., in association with old pyrenomycete stromata of Amphiporthe leiphaemia and Diaporthe sp., possibly also Coryneum umbonatum. Almost certainly fungicolous.
Sites are known in VC2 E Cornwall, VC7 N Wiltshire, VC13 W Sussex, VC15 E Kent, VC27 E Norfolk, VC34 W Gloucestershire and VC39 Staffordshire.