Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Thallus: crustose, thin, superficial to immersed, inconspicuous, continuous to somewhat cracked surface: gray to gray-green, smooth Apothecia: usually numerous, scattered or confluent, sessile to immersed. 0.2-0.4 mm in diam. disc: cream to orange, concave margin: smooth to crenate exciple: paler or concolorous, smooth to occasionally crenate hymenium: hyaline, 90-115 µm tall; paraphyses: capitate to 3-4 µm wide at tips asci: clavate, 8-spored ascospores: hyaline, "transversely" divided by sloping or diagonal septa, 6 or fewer cells visible in optical view, 9-18 x 6-8(-11) µm Spot tests: thallus K-, C-, KC-, P- Secondary metabolites: none detected. Substrate and ecology: on base-rich bark or in nutrient tracks on bark of deciduous trees World distribution: Europe and North America Sonoran distribution: Chihuahua. Note: Gyalecta flotowii differs from G. truncigena in its smaller, usually nearly spherical, fewer-celled ascospores.