Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.

Life habit: lichenized, although may appear lichenicolous when superficially growing on algal/lichen crusts Thallus: squamulose, attached by a loose rhizohyphal web, a central bundle of rhizohyphae or rhizines upper surface: continuous, pale to dark brown or greenish gray, dull, smooth or very minutely scabrose, partly with pruina deriving from disintegration of epinecral layer; soredia and isidia absent upper cortex: absent or as in Catapyrenium, epinecral layer amorphous, composed of dead collapsed cortical cells medulla: white, filamentous to subparaplectenchymatous photobiont: primary one a chlorococcoid alga, secondary photobiont absent lower surface: pale to blackish Ascomata: perithecial, laminal, broadly pyriform or subglobose, immersed, without or with a small apical involucrellum in one species; exciple: hyaline, brown or brown-black; interascal filaments: absent or soon disappearing (present in early stages of development); ostiolar filaments: present, simple or distally sparsely furcate asci: clavate, non-amyloid, thin-walled, apically slightly thickened, with a small indentation (ocular chamber), 8-spored ascospores: ellipsoid, ovoid or subfusiform, hyaline, 2-celled; walls: thin, smooth, without halo Conidiomata: not seen Secondary metabolites: none detected Geography: in arid, semi-arid and arctic-alpine regions of the Northern Hemisphere Substrate: on soil, detritus, bryophytes, calciferous or non-calcareous rocks or algal/lichen crusts. Notes: It is closely related to Catapyrenium s. str., from which it is separated by its septate ascospores and the type of ascus apex.