Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2002. Lichen Flora of the Greater Sonoran Desert Region. Vol 1.
Thallus: not well developed, 0.1 mm thick surface: white; soredia not developed Ascomata: developing erumpently, immersed to sessile, 0.2-0.5 mm diam; disc: convex; exciple: level with the disc, algae missing; proper exciple: sometimes inconspicuous; epithecium: 10-15 µm thick with hyphae richly branched and intertwined, verrucose, tips 2 µm diam.; hymenium: 55-65 µm high; hypothecium: dark-brown (carbonaceous) asci: clavate, 50-60 x 13 µm, 8-spored ascospores: fusiform, curved, hyaline, 19-22 x 4-5 µm Pycnidia: 0.1 mm diam conidia: bacilliform, curved, 6-9 x 1<2 µm Spot tests: thallus K-, C-, KC-, P- Secondary metabolite: roccellic acid. Substrate and ecology: Schismatomma rediunta has been found on bark of Juglans californica, Umbellularia californica and Heteromeles arbutifolia World and Sonoran distribution: Schismatomma rediunta is restricted to southern California on Santa Catalina and Santa Cruz Islands and on the nearby mainland in Santa Monica. Notes: Because it is inconspicuous, it is very rarely collected. The first recollection of Schismatomma rediunta since 1907 was made 1994.