Endococcus verrucisporus
Anamorph: not known.
Teleomorph: stromata absent. Ascomata perithecia, 150-180 µm diam., scattered or in large clusters, subglobose, becoming erumpent through the host thallus and ± completely exposed, with a shortly papillate neck, ostiolate, black. Peridium carbonaceous, comprising 3-6 layers of radially compressed thick-walled dark brown globose to angular cells to 9 µm diam. Interascal tissue absent, the ostiole lined internally with very short periphyses 8-12 µm long and 3-3.5 µm diam. Asci in a basal fascicle, forming in a gelatinized matrix, 30-38 x 12-17 µm, clavate to cylindric-clavate, with a markedly thickened apex when young, fissitunicate, not staining in iodine, 8-spored. Ascospores biseriately arranged, (9-) 9.5-13.5 (-14.5) x 5.5-7.5 (-8) µm, ellipsoidal to broadly ellipsoidal, the ends rounded, hardly constricted at the single ± median septum, dark brown, thick-walled, verrucose (best observed in immature spores), without a perispore, gelatinous sheath or appendages.
Not evaluated by Woods & Coppins (2012), but listed as Nationally Rare.
Characterised especially by its verrucose ascospores, which appear to have internal ornamentation that is obscured when the spore becomes melanized at maturity.
On thalli of Ionaspis lacustris, not causing substantial damage to the host lichen.
In GB&I, scattered in western parts of Britain and Ireland, from mid Wales through Cumbria to Scotland and Ireland.