Pirottaea brevipila
Anamorph: not known.
Teleomorph: ascomata apothecia, erumpent and becoming ± superficial, scattered or in small clusters, 250-450 µm diam. and 100-150 µm high, black, appearing verrucose when dry. Exciple 20-25 µm thick at the base, slightly narrower towards the rim of the apothecium, composed of dark brown thin-walled angular to angular-globose cells 7-10 µm diam., tending to elongate towards the rim, with short dark brown opaque processes covering the upper part of the exciple and merging into short blunt irregular dark brown spines 20-30 µm in length and 4-5 µm diam. surrounding the grey disc. Interascal tissue of thin-walled hyaline paraphyses 1.5-2 µm diam., branched at the base, the apex not clearly differentiated. Asci 45-55 x 8-9.5 µm, cylindric-fusiform and tapering towards the ± acute apex, quite thin-walled, almost sessile, croziers not seen, not blueing in iodine, 8-spored. Ascospores arranged in a fascicle, 27-31 x 2.5-3 µm, narrowly fusiform-ellipsoidal, often slightly curved, 1- to 3-septate, hyaline, thin- and smooth-walled, without a gelatinous sheath.
On dead stems of Centaurea nigra and C. scabiosa, presumably saprotrophic. Also reported from Cirsium arvense.
Scattered throughout England, mostly in the south, and Scotland (Mull, VC103 Mid Ebudes).