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Porpidia melinodes (Korber) Gowan & Ahti
Family: Lecideaceae
[Aspicilia melinodes Körb.,  more]
Porpidia melinodes image

Global occurrence: Eurasia – Asia Extratropical | 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 | cracked, fissured, fractured, rimose | compartimentized – areolate, squamulate; [th] upper surface: red(dish) | yellow(ish) brown | yellow(ish) red (orange red); [th marginal and upper surface] specific structures: present; [th margin] cilia, cilioid structures: absent; [th upper surface] isidia, isidioid structures: absent; [th upper surface] soredia, soralia, soralioid structures: present; [th] morphol substructures (eg areoles, lobes, branches) upper surface: smooth, plane; [th] medulla amyloidity: absent.  Ascomata: absent | present; ascoma: apothecial, apothecioid – hymenial; ascoma [mm]: (low) 1.5 (high) 3.0; ascoma: sessile, superficial; [ascm, if apoth] disc, mazaedium: plane, flat, flattened, expanded | subconvex, slightly convex; [ascm, if apoth] disc, mazaedium: black(ish); [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: brown(ish) (if pale: fawn, tan; if mid: cinnamon); [ascm] paraphyses/-oids: present.  Asci: lecanoralean; [asc] tholus: thickened; [asc] tholus amyloidity (iodine reaction): present; [asc] tholus amyloidity pattern: with amyloid tube, ring (= Collema-, Micarea-, Porpidia-, Psora-types etc).  Ascospores: (median) 8.0; [asp] shape: ellipsoidal; [asp] length [µm]: (low) 14.0 (high) 26.0; [asp] width [µm]: (low) 6.5 (high) 12.5; [asp] septa: absent – spore lumen unilocular, monolocular; [asp] pigmentation: hyaline, colourless; [asp] perispore, epispore: not apparent | thin, thinly halonate | thick, distincly halonate.  Conidiomata: absent | present.  Conidia: bacilliform, bacillary.  Secondary metabolites: absent | present, 2'-O-methylhyperlatolic acid | confluentic acid | norstictic acid | stictic acid.  Primary photobiont: present, chlorophytaceous – trebouxiaceous, chlorococcoid.  Secondary photobionts (eg in cephalodia): absent.