Global occurrence: Eurasia – Europe | Americas – North America (incl Mexico) | Arctic. Substrate: rock – siliceous, siliciferous, acidic | rock – calcareous, calciferous, basic. Life habit: lichenized (mutualistic with algal photobionts). Thallus: crustose (crustaceous) – endosubstratal, inconspicuous, immersed; [th] upper surface: white(ish); [th marginal and upper surface] specific structures: absent. Ascomata: absent | present; ascoma: apothecial, apothecioid – hymenial; ascoma [mm]: (min) 0.6. 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] length [µm]: (min) 13.0 (low) 15.0 (high) 20.0 (max) 22.0; [asp] width [µm]: (low) 6.0 (high) 9.0; [asp] septa: absent | present – spore lumen bilocular, polarilocular, plurilocular; transversely septate; [asp] pigmentation: hyaline, colourless; [asp] perispore, epispore: not apparent. Secondary metabolites: present, unknown/unidentified anthraquinone(s). Primary photobiont: present, chlorophytaceous – trebouxiaceous, chlorococcoid. Secondary photobionts (eg in cephalodia): absent.