Global occurrence: Eurasia – Asia Extratropical | Eurasia – Europe | Americas – North America (incl Mexico) | Eurasia – Asia Tropical | Arctic. Substrate: rock – siliceous, siliciferous, acidic. Life habit: lichenized (mutualistic with algal photobionts). Thallus: crustose (crustaceous) – episubstratal – unspecified; compartimentized – areolate, squamulate; [th] upper surface: brown(ish) (if pale: fawn, tan; if mid: cinnamon) | white(ish) brown (beige); [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: absent | present; [th] morphol substructures (eg areoles, lobes, branches) width [mm]: (median) 1.2. Ascomata: absent. Secondary metabolites: present; gyrophoric acid. Primary photobiont: present; chlorophytaceous – trebouxiaceous, chlorococcoid. Secondary photobiont (eg in cephalodia): present.