Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.

Apothecia: initially immersed, later erumpent, dispersed or aggregated, black, ±round, 150-225 µm in diam. gin: in opened ascomata 60-125 µm thick, generally with 3-5 deep marginal fissures, rarely almost smooth (mainly when young); ascomatal pore: 25-50(-75) µm wide exciple: laterally green to olivaceous, K+ olivaceous brown, 20-45 µm thick, basally greenish brown, 25-45 µm thick; excipular hairs: olivaceous, 20-50 x 2.5-3 µm epihymenium: hyaline to pale olivaceous hymenium: hyaline, 35-60 µm thick asci: cylindrical to elongate clavate, 40-50 x 6-8 µm ascospores: hyaline, 0(-1)-septate, ellipsoid, (5-)6-12 x 3-4(-4.5) µm. Hosts: on Tephromela atra and T. tropica; in Arizona on World distribution: Europe, Macaronesia, Africa, North and South America and the subantarctic Islands Sonoran distribution: collected once in Arizona at 3000 m. Notes: Skyttea tephromelarum, described from Tephromela tropica, is doubtfully distinct from S. elachistophora (Nyl.) Sherwood & D. Hawksw., Trans. Br. Mycol. Soc.