Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2007. Lichen Flora of the Greater Sonoran Desert Region. Vol 3.
Thallus: crustose, thin, small areolate, granulose to coralloid areoles: small, 0.15-0.75 mm wide, thin, initially usually effigurate at the margin, becoming granulose to coralloid towards the center upper surface: reddish black, dull, usually granulose isidia: absent, but coralloid granules may appear "isidioid" lower surface: attached by rhizohyphae or gelatinous basal layer Apothecia: rarely developed, semi-immersed to sessile, small, 0.2-0.45 mm wide disc: at first punctiform, later depressed and ±open, black, with persisting, granulose thalline margin proper exciple: very thin, 7-10 µm wide epihymenium: yellowish brown, K- hymenium: hyaline, 90-120 µm high, IKI+ blue asci: cylindrical to subclavate, 8-spored ascospores: simple, hyaline, broad ellipsoid to subglobose, 9-13 x 7-8 µm Pycnidia: immersed, simple, ±globose, c. 100 x 100 µm conidia: ellipsoid, c. 3 x 1 µm Spot tests: all negative Secondary products: none detected. Substrate and ecology: on acidic rock World distribution: SW Europe, NW Africa, Canary Islands and SW North America Sonoran distribution: southern California (Santa Cruz Island), Baja California, Baja California Sur, and Sonora. Notes: Pyrenopsis triptococca is usually recognized by its effigurate thallus margin. However, the marginal areoles are very small and not distinctly elongated, as occurs in Pterygiopsis atra Vain. Sometimes, the effigurate marginal areoles are lacking and the thallus appears mostly granulose-areolate. Pyrenopsis triptococca otherwise differs from similar crustose Lichinaceae by its dark reddish thallus.