Life habit: lichenized Thallus: gelatinous when wet, fruticose, foliose-fruticose, dwarf fruticose, umbilicate-peltate or squamulose, rarely almost crustose, usually with deeply divided lobes, lobules often terete, sometimes knotty, more rarely flattened surface: black, grayish pruinose, smooth or folded, sometimes gyrose isidia: lacking, but erect, cylindrical lobules or small globose granules on the lobe surface may appear as isidia anatomy: ecorticate, heteromerous, with a compact or fairly loose central strand of abundant or few periclinally arranged or intricate hyphae, anatomy reticulate towards the thallus periphery photobionts: primary one a chroococcoid cyanobacterium, secondary photobiont absent Ascomata: absent or present, apothecioid, marginal, laminal or terminal, orbicular, semi-immersed to sessile or stipitate, thalloid rim distinct to prominent, persisting ascoma ontogeny: hemiangiocarpous, single ascogonia arising freely beneath the thallus surface Ascoma anatomy: proper exciple: absent, epihymenium: indistinct but upper parts of the hymenium conspicuously reddish brown to dark brown colored due to ascus walls that after spore discharge decay and become ▒intense brown, usually K+ brown-purple, rarely K-, hymenium: hyaline, IKI+ deep blue, paraphyses: distinctly septate, sparsely branched and anastomosing, terminal cells clavate; subhymenium: hyaline, IKI+ blue, elongated as stipe and usually connected to the central hyphal strand asci: clavate, prototunicate, thin walled, non-amyloid but with a distinct amyloid outer cap. 8-spored ascospores: hyaline, simple, narrow to broad ellipsoid or globose, (5-)7.5-10(-12.5) x 5-7.5 Ám, thin walled Conidiomata: absent or present, pycnidial, marginal, laminal or terminal, pyriform to ellipsoid, immersed to semi-immersed, hyaline, walls not convoluted; conidiophores: terminally branched, cells elongated conidia: acicular, filiform to sigmoid, large, c. 15-40 x 1 Ám, acrogenous Secondary metabolites: not detected Geography: world-wide, in arid to semi-arid regions Substrate: usually on calcareous rock or calciferous soils and soil crusts, rarely on siliceous rock and derived mineral soil. Notes: The above description refers to typical species of the genus and explicitly excludes Peccania arizonica. This species does not belong to Peccania s. str. According to ICBN (St. Louis Code), app. IIIA, Peccania has been conserved against Corinophoros A. Massal. in Flora 39: 212 (14 Apr 1856).