Pulvinora Davydov, Yakovczenko & Printzen, gen. nov.
MycoBank number: MB 838000; Index Fungorum number: MB 838000; Facesoffungi number: FoF;
The genus is distinguished from other genera within Lecanoraceae by the combination of characters, namely Lecanora-type asci, mycolecanorine apo- thecia soon becoming convex with a photobiont layer under the hypothecium, and a pulvinate thallus with squamules at the tips of the pseudopodetia-like branched pale brownish structures.
TYPE SPECIES: Pulvinora stereothallina Davydov & Yakovczenko.
Etymology: From Latin ‘pulvinar’ ( cushion or pillow), which refers to the typical cushion-like, thick thallus, and ‘nora’ reminiscent of ‘Lecanora’, the type genus of Lecanoraceae that gave the name for the Lecanora-type asci in Pulvinora.
Description: Thallus pulvinate, bullate-squamulose to distinctly stalked, small-fruticose and coralloid, lead-grey, brownish-grey, violet-brown-grey thick cushions, loosely attached to the substrate, without vegetative propagules, without prothallus, resembling Stereocaulon species; squamules/bullate areoles located at the tip of pseudopodetia-like, branched, beige to brownish structures, rounded to irregular, first convex then plane and concave, with crenulated and somewhat swollen margin, coalescing into clusters up to 12 mm wide. Apothecia ca. 1– 3 mm in diam., numerous, single or coalescing into clusters up to 7 mm in diam., resembling those of Miriquidica species, protruding above the thallus surface, stipitate, at the tip of the pseudopodetia-like branched brownish structures, initially plane with thin black margin up to 0.1 mm wide, soon strongly convex to spherical with excluded margin, mycolecanorine (with a contiguous photobiont layer below the hymenium that does not extend into the persistent thalline exciple (amphithecium); disc black (not changing color when wet), rounded, irregular to crenulate, cracked, uneven, shiny, rarely dull, without pruina. Asci clavate, 8-spored, Lecanora-type; ascospores simple or rarely with a thin septum, colorless, narrowly-ellipsoid, sometimes with one attenuated tip. Photobiont trebouxioid.
Chemistry: Stictic acid complex, psoromic, alectorialic, norstictic acid and atranorin detected by TLC in thallus in different combinations.
Substrate and ecology: On siliceous rocks in the alpine or subalpine belt.
Distribution: Asia (Altai) and North America (Rocky Mountains, Cascade Range and the Sierra Nevada).
Species