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Lecidea praenubila Nyl.
Family: Lecideaceae
Lecidea praenubila image

Global occurrence: Eurasia – Europe | Americas – North America (incl Mexico) | Arctic.  Substrate: rock – siliceous, siliciferous, acidic | rock, stones, pebbles – unspecified.  Life habit: lichenized (mutualistic with algal photobionts).  Thallus: crustose (crustaceous) – episubstratal – unspecified; thallus: continuous, diffuse, effuse | compartimentized – areolate, squamulate; [th] upper surface: black(ish) | white(ish) grey | grey(ish) brown | yellow(ish) brown; [th upper surface]: epruinose; [th marginal and upper surface] specific structures: absent; [th] morphol substructures (eg areoles, lobes, branches) width [mm]: (min) 3.0; [th] medulla amyloidity: present.  Ascomata: absent | present; ascoma: apothecial, apothecioid – hymenial; ascoma [mm]: (low) 0.5 (high) 2.0 (max) 3.0; ascoma: immersed, innate; [ascm, if apoth] disc, mazaedium: plane, flat, flattened, expanded | subconvex, slightly convex; [ascm, if apoth] disc, mazaedium: black(ish) | grey(ish); [ascm, if apoth] disc, mazaedium: epruinose | pruinose; [ascm, if apoth] margin surface; [if perith] periostiolar area, ostiole, involucrellum: brown(ish) (if pale: fawn, tan; if mid: cinnamon); [ascm, if apoth] margin excipular photobionts: present; [ascm, if apoth] subhymenial layers, hypothecium; [if perith] basal excipulum: black(ish) | brown(ish) (if pale: fawn, tan; if mid: cinnamon); [ascm] paraphyses/-oids: present; [ascm] paraphyses/-oid cells width [µm]: (low) 1.5 (high) 2.0; [ascm] paraphyses/-oid apical cells width [µm]: (min) 5.0; [ascm] epihymenium, epithecium: green(ish) | brown(ish) (if pale: fawn, tan; if mid: cinnamon).  Asci: lecanoralean; [asc] tholus: thickened; [asc] tholus amyloidity (iodine reaction): present; [asc] tholus amyloidity pattern: with amyloid cap (= Icmadophila-, Lecidea-, Pertusaria-types etc).  Ascospores: (median) 8.0; [asp] shape: ellipsoidal; [asp] length [µm]: (min) 7.0 (low) 9.0 (high) 14.0 (max) 17.0; [asp] width [µm]: (min) 3.5(median) 7.0 (max) 10.0; [asp] septa: absent – spore lumen unilocular, monolocular; [asp] pigmentation: hyaline, colourless; [asp] perispore, epispore: not apparent.  Conidiomata: absent | present.  Conidia: bacilliform, bacillary; [co] length [µm]: (low) 7.0 (high) 10.0 (max) 12.0.  Secondary metabolites: present, stictic acid.  Primary photobiont: present, chlorophytaceous – trebouxiaceous, chlorococcoid.  Secondary photobionts (eg in cephalodia): absent.