[Leptogium contortum Sierk]
Nash, T.H., Ryan, B.D., Gries, C., Bungartz, F., (eds.) 2004. Lichen Flora of the Greater Sonoran Desert Region. Vol 2.
Thallus: dwarf-fruticose, forming a crust-like cushion, 1-2 cm wide lobes: terete to somewhat flattened, up to 1 mm long, 0.1-0.2 mm wide, 100-200 µm thick surface: olivaceous brown to brown, smooth, not isidiate internal anatomy: with upper and lower cortices consisting of irregularly isodiametrical cells 5-9 µm in diam., internally paraplectenchymatous and with loosely interwoven chains of Nostoc Apothecia: not observed Pycnidia: not observed Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on soil over granite in pinyon-juniper woodlands World distribution: southwestern North America Sonoran distribution: technically occurring just outside of the Sonoran region. Note: Thus far, it is only known from Colorado National Monument just outside the Sonoran region. Its type of habitat is common in northern Arizona, and consequently it should eventually be found within the Sonoran region. Eventually this species may prove to a terrestrial form of L. teretiusculum although its olivaceous color is thought to be distinctive.