Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2007. Lichen Flora of the Greater Sonoran Desert Region. Vol 3.
Thallus: squamulose-umbilicate, sometimes almost stipitate, squamules 0.25-2 mm wide, roundish, entire, crenate or finally divided into laterally compressed, densely aggregated lobules (0.2-0.3 mm thick) with flattened tips upper surface: black, dull, at first smooth, becoming superficially crenate or notched to irregularly tessellate, margin entire to crenate lower surface: attached to the substrate by small, sometimes elongated umbilicus thallus anatomy: homoiomerous, mycobiont cells short-celled to elongated, angulate to roundish, c. 5-10 x 2.5-5 µm, photobiont cells large, 12.5-20 µm including gelatinous sheath, sheath yellowish brown, K-, c. 2-3 µm thick Apothecia: semi-immersed to sessile, ±round to finally often laterally compressed or sinuose, 0.25-0.5(-0.6) mm wide, disc: dark red, depressed; margin thalline,: thick, 75-125 µm wide, prominent, persisting, smooth or becoming crenate; proper exciple: lacking epihymenium: faintly yellowish brown, K- hymenium: hyaline, IKI+ blue, up to 125 µm tall; paraphyses: distinctly septate, branched and anastomosing, apical cells up to 3 µm wide; subhymenium: hyaline, inversely cone-shaped, sometimes elongated as a stipe, IKI+ blue ascus: subclavate, thin walled, IKI-, 8-spored ascospores: hyaline, simple, broad ellipsoid, 10-12.5 x 5-7.5 µm, thin walled ascoma ontogeny: ascogones arising free in groups of 3-4 Pycnidia: immersed, globose, up to 0.125 mm wide, simple or with convoluted walls when old conidia: small, ellipsoid, c. 3-5 x 1.5 µm Spot tests: all negative Secondary products: none detected. Substrate and ecology: on volcanic rock on shaded boulders in rocky slopes and pebbles on ground in more exposed situations World and Sonoran distribution: common in the Sierra la Giganta in Baja California Sur, a single record from Sinaloa. Notes: The species is distinguished from Phloeopeccania pulvinulina by its larger squamules and apothecia, thicker lobules, larger ascospores and constantly 8-spored asci. Phylliscum demangeonii, a species known from northern California, is similar in its umbilicate-rosette shaped thallus and tessellate thallus surface. It deviates, however, in the lack of paraphyses and in the presence of punctiform apothecial discs and polysporous asci with pointed tips. Paulia myriocarpa is also similar but has regularly tessellate squamules with distinctly effigurate margins. The apothecia are small and the thalline margin is not prominent. Species of Anema are similar as well, but differ in the type of ascomal ontogeny (pycnoascocarp).