Global occurrence: Eurasia – Europe | Americas – North America (incl Mexico).  Substrate: rock – siliceous, siliciferous, acidic.  Life habit: lichenized (mutualistic with algal photobionts).  Thallus: crustose (crustaceous) – episubstratal – unspecified; [th] upper surface: yellow(ish) red (orange red); [th marginal and upper surface] specific structures: absent; [th] medulla amyloidity: present.  Ascomata: absent | present; ascoma: apothecial, apothecioid – hymenial.  Asci: lecanoralean; [asc] tholus: thickened; [asc] tholus amyloidity (iodine reaction): present; [asc] tholus amyloidity pattern: with amyloid tube, ring (= Collema-, Micarea-, Porpidia-, Psora-types etc).  Ascospores: [asp] septa: absent – spore lumen unilocular, monolocular; [asp] pigmentation: hyaline, colourless.  Primary photobiont: present, chlorophytaceous – trebouxiaceous, chlorococcoid.  Secondary photobionts (eg in cephalodia): absent.