Global occurrence: Africa (incl Madagascar) | Oceania – Australasia | Eurasia – Europe | Americas – North America (incl Mexico) | Americas – South and Central America | Arctic.  Substrate: bark, cork, plant surface – trunks, branches, twigs.  Life habit: lichenized (mutualistic with algal photobionts).  Thallus: crustose (crustaceous) – endosubstratal, inconspicuous, immersed | crustose (crustaceous) – episubstratal – unspecified; [th] upper surface: grey(ish) | brown(ish) (if pale: fawn, tan; if mid: cinnamon); [th marginal and upper surface] specific structures: absent.  Ascomata: absent | present; ascoma: apothecial, apothecioid – hymenial; ascoma [mm]: (low) 0.5 (high) 1.5; [ascm, if apoth] disc, mazaedium: concave; [ascm, if apoth] disc, mazaedium: black(ish); [ascm, if apoth] disc, mazaedium: epruinose; [ascm, if apoth] margin surface; [if perith] periostiolar area, ostiole, involucrellum: black(ish); [ascm, if apoth] margin excipular photobionts: absent; [ascm, if apoth] subhymenial layers, hypothecium; [if perith] basal excipulum: hyaline, colourless | brownish hyaline; [ascm] paraphyses/-oids: present; [ascm] epihymenium, epithecium: green(ish) | brown(ish) (if pale: fawn, tan; if mid: cinnamon).  Asci: fissitunicate – bitunicate; [asc] tholus: thickened; [asc] tholus amyloidity (iodine reaction): absent | present; [asc] tholus amyloidity pattern: with amyloid tube, ring (= Collema-, Micarea-, Porpidia-, Psora-types etc).  Ascospores: (median) 8.0; [asp] length [µm]: (low) 15.0 (high) 20.0; [asp] width [µm]: (low) 4.5 (high) 6.0 (max) 7.0; [asp] septa: present, transversely septate; [asp] transversal septa: (median) 3.0 (max) 4.0; [asp] pigmentation: hyaline, colourless; [asp] perispore, epispore: not apparent.  Secondary metabolites: absent.  Primary photobiont: present, chlorophytaceous – trentepohliaceous, trentepohlioid.  Secondary photobionts (eg in cephalodia): absent.