Global occurrence: Oceania – Australasia | Eurasia – Europe | Americas – North America (incl Mexico) | Americas – South and Central America.  Substrate:   soil, clay, humus, turf, detritus, dead leaves | wood – dead, living | rock, stones, pebbles – unspecified.  Life habit: lichenized (mutualistic with algal photobionts).  Thallus: crustose (crustaceous) – endosubstratal, inconspicuous, immersed; [th] upper surface: yellow(ish) (if dull: buff); [th upper surface]: pruinose; [th marginal and upper surface] specific structures:  absent.  Ascomata: absent | present; ascoma: apothecial, apothecioid – hymenial | perithecial, perithecioid – hymenial; ascoma [mm]: (low) 0.15 (high) 0.3; ascoma: subsessile, subimmersed, adnate, semi-immersed, emergent | sessile, superficial; [ascm, if apoth] disc, mazaedium: yellow(ish) (if dull: buff);[ascm, if apoth] disc, mazaedium: pruinose; [ascm, if apoth] disc, mazaedium pruina: scarce, sparse, fine | dense; [ascm, if apoth] margin excipular photobionts: absent; [ascm] paraphyses/-oids: present.  Asci: unitunicate; [asc] tholus: not thickened | thickened; [asc] tholus amyloidity (iodine reaction): present; [asc] tholus amyloidity pattern: with amyloid tube, ring (= Collema-, Micarea-, Porpidia-, Psora-types etc) | with amyloid cap (= Icmadophila-, Lecidea-, Pertusaria-types etc).  Ascospores: (low) 50.0 (high) 300.0; [asp] shape: subglobose, subspherical | broadly ellipsoidal | ellipsoidal; [asp] length [µm]: (low) 1.5 (high) 4.0 (max) 6.0; [asp] width [µm]: (low) 1.5 (high) 2.0; [asp] septa: absent – spore lumen unilocular, monolocular; [asp] pigmentation: hyaline, colourless; [asp] perispore, epispore: not apparent.  Secondary metabolites: present, pulvinic acid.  Primary photobiont: present, chlorophytaceous – trebouxiaceous, chlorococcoid.  Secondary photobionts (eg in cephalodia): absent.