Thallus: suffruticose, in patches up to 3 cm in diam. squamules: up to 1.5 mm long, club-shaped upper surface: dark olive-black to black isidia: sometimes present, minute, laminal; not sorediate upper cortex: lacking but with a yellow to brownish epinecral layer (3-6 µm thick) medulla: almost completely hollow; hyphae: peripheral, 1.5-2 µm thick, elongated, loosely interwoven; algal layer: delimited to the 30-50 µm thick outer part lower cortex: not developed Apothecia: (only known from Australian material) 1-3, immersed; disc: punctiform, up to 0.2 mm in diam. asci: clavate, I+ wine-red but blue after pretreatment with K, >64-spored ascospores: globose, 3.5-4.7 µm diam. Pycnidia: no data available conidia: fusiform, 3.7-4.3 x 1.2-1.8 µm Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: on acidic rocks in arid woodlands World distribution: SW North America, NE Brazil, southern Africa and northern Australia Sonoran distribution: desert transition areas of SE Arizona.