Pyrenopsis grumulifera
Thallus: not clearly differentiated.
Anamorph: conidiomata similar in structure to the ascomata. Conidiogenous cells 3-5 x 1.5-2 µm, ellipsoidal to doliiform with an attenuated apical region, probably proliferating percurrently. Conidia 2.5-3.5 x ca 1 µm, bacillar, hyaline, aseptate, thin- and smooth-walled.
Teleomorph: ascomata in small clusters on a cyanobacterial mat, apothecia, ± immersed to superficial, 55-80 µm diam. and 40-60 µm tall, urecolate to cupulate, the opening 30-40 µm diam., sessile, slightly constricted at the base, with a broad ± smooth margin, glossy black. Excipulum composed of thick olivaceous ± parallel to interspersed hyphae 3-4 µm diam. within a gelatinous matrix, paler underneath, without hairs. Interascal tissue composed of thin-walled unbranched paraphyses ca 2 µm diam. within a gelatinous matrix, with an epithecial gelatinous layer that stains blue in Lugol's iodine. Asci 44-55 x 9-12 µm, cylindric-clavate, short-stalked, fairly thick-walled with rostrate dehiscence, the apex rounded, the wall and contents showing a strong dextrinoid reaction in Lugol's iodine, the walls of discharged asci persisting, 8- to 16-spored. Ascospores arranged biseriately, 10-5-12 x 3-3.5 µm, ellipsoidal to clavate, slightly constricted in the central part and appearing to have a narrow ± median septum [a pseudoseptum], hyaline, thin-walled, smooth, without an epispore or gelatinous sheath.
Assessed by Woods & Coppins (2012) as Data Deficient, and listed as Nationally Rare.
The species is poorly understood and the variation in ascospore number (and size) makes identification problematic. Those of the collections examined have substantially longer spores than indicated in Gilbert & Coppins (2009), but fall within the measurements given by Jørgensen (2012).
Scattered throughout montane regions, fairly widespread in Scotland and N Wales, also present in Cumbria. BLS map here.
On a cyanobacterial mat (containing Gloeocapsa )over siliceous rock, associated with Lepraria caesioalba or Micarea coppinsii.