Anamorph: conidiomata pycnidia, (140-)170-200 µm diam., initially immersed in moribund podetia of the host, becoming almost superficial, subglobose, black, inconspicuously ostiolate. Conidiomatal wall composed of angular cells, the outer layer dark brown and thick-walled, the inner layer hyaline. Conidiophores absent. Conidiogenous cells ca 4 µm long and 3 µm diam., ampulliform, hyaline, arising from the innermost cell layer lining the pycnidial cavity, proliferation unclear. Conidia (21-) 22.5-26.5 x 2.7-3.1 µm, cylindrical to cylindric-fusiform, the broadest part often towards the base, straight or sometimes slightly curved, the base ± truncate and the apex obtuse, almost all 3-septate, pale yellowish, smooth, without appendages or a gelatinous sheath.
Teleomorph: not known.
Not formally assessed, but likely to be rare as the conidiomata are quite conspicuous. The host specificity is uncertain.
Similar to Phaeoseptoria peltigerae but with larger conidia. The genus is diverse as a saprotroph of plants, and this species could have jumped hosts.
On moribund or dead podetia of Cladonia furcata, in association with Heterocephalacria bachmannii and Lichenoconium erodens.
Known from a single site in VC3 S Devon.