Global occurrence: Africa (incl Madagascar) | Eurasia – Asia Extratropical | Eurasia – Europe | Americas – North America (incl Mexico) | Americas – South and Central America | Eurasia – Asia Tropical | Arctic.  Substrate: bark, cork, plant surface – trunks, branches, twigs | rock – siliceous, siliciferous, acidic.  Life habit: lichenized (mutualistic with algal photobionts).  Thallus: fruticose (fruticous), shrub-like, beard-like; [th] upper surface: black(ish) | brown(ish) (if pale: fawn, tan; if mid: cinnamon); [th marginal and upper surface] specific structures: absent.  Ascomata: absent.  Secondary metabolites: present; fumarprotocetraric acid.  Primary photobiont: present; chlorophytaceous – trebouxiaceous, chlorococcoid.  Secondary photobionts (eg in cephalodia): absent.