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Melanelia agnata (Nyl.) Thell
Family: Parmeliaceae
[Cetraria agnata (Nyl.) Kristinsson]
Melanelia agnata image

Global occurrence: Eurasia – Europe | Americas – North America (incl Mexico).  Substrate: rock, stones, pebbles – unspecified.  Life habit: lichenized (mutualistic with algal photobionts). Thallus: foliose (foliaceous), leaf-like; continuous, diffuse, effuse; [th] upper surface: brown(ish) black | green(ish) brown (olive brown); [th marginal and upper surface] specific structures: absent; [th] morphol substructures (eg areoles, lobes, branches) width [mm]: (low) 0.5 (high) 2.5; [th] morphol substructures (eg areoles, lobes, branches) upper surface: rugose, plicate, folded, pustulate, faveolate, wrinkled | pseudocyphellate, with pseudocyphellae; [th] lower surface: brown(ish) (if pale: fawn, tan; if mid: cinnamon); [th lower surface] specific structures: present; [th lower surface] rhizines, rhizoid structures: present; [th lower surface] rhizines, rhizinoid structures: unbranched, simple.  Ascomata: absent | present; ascoma: apothecial, apothecioid – hymenial; ascoma [mm]: (min) 5.0; [ascm] paraphyses/-oids: present.  Asci: lecanoralean; [asc] tholus: thickened; [asc] tholus amyloidity (iodine reaction): present; [asc] tholus amyloidity pattern: amyloid with widening axial body towards the apex (= Lecanora-, Parmelia-, Rinodina-types etc).  Ascospores: (median) 8.0; [asp] shape: ellipsoidal; [asp] length [µm]: (low) 6.8 (high) 8.5; [asp] width [µm]: (low) 4.8 (high) 6.6; [asp] septa: absent – spore lumen unilocular, monolocular; [asp] pigmentation: hyaline, colourless; [asp] perispore, epispore: not apparent | thick, distincly halonate.  Conidiomata: absent | present.  Conidia: bifusiform; [co] length [µm]: (low) 5.0 (high) 7.5.  Secondary metabolites: absent.  Primary photobiont: present, chlorophytaceous – trebouxiaceous, chlorococcoid.  Secondary photobionts (eg in cephalodia): absent.