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

Thallus: crustose, continuous, granulose to rimose, 0.6-1 mm thick; prothallus: absent or present surface: white to greenish yellow to whitish gray, dull to weakly glossy, without soredia or isidia Apothecia: semi-immersed to sessile, slightly to strongly constricted at base, 0.8-1.2 mm in diam. disc: black, plane to convex to rarely strongly convex, epruinose margin: distinct to prominent, thin, c. 0.075 mm wide, persistent to becoming excluded exciple: bluish to greenish black, without algal cells parathecium: yellowish to reddish brown, without crystals epihymenium: green, blackish green to bluish green hymenium: hyaline, 50-90 µm tall, not inspersed; paraphyses: simple, rarely anastomosing or branched, not to slightly thickened apically hypothecium: reddish brown to rarely yellowish brown asci: clavate, lecanoral, 8-spored ascospores: hyaline, simple, broadly ellipsoid to ovoid, 9-14 x 5.5-7.5 µm; wall: thick and smooth not halonate Pycnidia: not seen Spot tests: K-, C-, KC-, P- Secondary metabolites: diploicin and lichexanthone. Substrate and ecology: on bark World distribution: temperate areas of Asia, Europe, and North America (to north-central Mexico) Sonoran distribution: only known from northeastern Arizona. Notes: Lecidella tumidula can be distinguished from L. elaeochroma mainly by its smaller apothecia, less thick hypothecium, smaller spores, a non-inspersed hymenium, and a different chemistry.