Global occurrence: Africa (incl Madagascar) | Eurasia – Asia Extratropical | Eurasia – Europe | Americas – North America (incl Mexico) | Eurasia – Asia Tropical | Arctic. Substrate: rock – siliceous, siliciferous, acidic | rock, stones, pebbles – unspecified. Life habit: lichenized (mutualistic with algal photobionts). Thallus: fruticose (fruticous), shrub-like, beard-like; continuous, diffuse, effuse; [th] upper surface: green(ish); [th upper surface]: epruinose; [th marginal and upper surface] specific structures: present; [th margin] cilia, cilioid structures: absent; [th upper surface] isidia, isidioid structures: absent; [th upper surface] soredia, soralia, soralioid structures: present; [th] morphol substructures (eg areoles, squamules): distantly discontiguous; [th] morphol substructures (eg areoles, lobes, branches) upper surface: smooth, plane | verrucose, warted; [th] morphol substructures (eg lobes, branches): irregular. Ascomata: absent | present; ascoma: apothecial, apothecioid – hymenial; ascoma: pedicellate, stipitate, pedunculate, stalked; [ascm, if apoth] disc, mazaedium: concave | subconvex, slightly convex; [ascm, if apoth] disc, mazaedium: epruinose | pruinose; [ascm, if apoth] margin surface; [if perith] periostiolar area, ostiole, involucrellum: green(ish); [ascm, if apoth] margin excipular photobionts: present | abundant. Asci: lecanoralean; [asc] tholus: thickened; [asc] tholus amyloidity (iodine reaction): present; [asc] tholus amyloidity pattern: amyloid with acuate axial body towards the apex (= Bacidia-, Buellia-, Ramalina-types etc). Ascospores: (median) 8.0; [asp] shape: broadly ellipsoidal; [asp] length [µm]: (low) 12.0 (high) 16.0; [asp] width [µm]: (low) 4.0 (high) 6.0; [asp] septa: present, transversely septate; [asp] transversal septa: (median) 1.0; [asp] pigmentation: hyaline, colourless; [asp] perispore, epispore: not apparent. Conidiomata: absent | present. Conidia: bacilliform, bacillary. Secondary metabolites: present, usnic acid. Primary photobiont: present, chlorophytaceous – trebouxiaceous, chlorococcoid. Secondary photobionts (eg in cephalodia): absent.