Global occurrence: Eurasia – Europe | Americas – North America (incl Mexico) | Arctic.  Substrate: rock – siliceous, siliciferous, acidic.  Life habit: lichenized (mutualistic with algal photobionts).  Thallus: crustose (crustaceous) – episubstratal – unspecified; cracked, fissured, fractured, rimose | compartimentized – areolate, squamulate; [th] upper surface: grey(ish) | grey(ish) brown; [th marginal and upper surface] specific structures: absent; [th] morphol substructures (eg areoles, lobes, branches) upper surface:  smooth, plane | verrucose, warted; [th] medulla amyloidity: absent.  Ascomata:  absent | present; ascoma: apothecial, apothecioid – hymenial; ascoma [mm]: (median) 1.5 (max) 2.5; ascoma: immersed, innate; [ascm, if apoth] disc, mazaedium: plane, flat, flattened, expanded | subconvex, slightly convex; [ascm, if apoth] disc, mazaedium: brown(ish) (if pale: fawn, tan; if mid: cinnamon) | brown(ish) black; [ascm] paraphyses/-oids: present.  Asci: lecanoralean; [asc] tholus: thickened; [asc] tholus amyloidity (iodine reaction): present; [asc] tholus amyloidity pattern: entirely amyloid (= Catillaria-, Teloschistes-types etc).  Ascospores: (median) 8.0; [asp] shape: broadly ellipsoidal; [asp] length [µm]: (low) 7.5 (high) 10.5; [asp] width [µm]: (low) 4.0 (high) 7.0; [asp] septa: absent – spore lumen unilocular, monolocular; [asp] perispore, epispore: not apparent.  Secondary metabolites: present, divaricatic acid.  Primary photobiont: present, chlorophytaceous – trebouxiaceous, chlorococcoid.  Secondary photobionts (eg in cephalodia): absent.