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Placynthium rosulans (Th. Fr.) Zahlbr.
Family: Placynthiaceae
Placynthium rosulans image
Life habit: lichenized (mutualistic with algal photobionts) thallus: placodioid-crustose, placodioid-foliose [th] upper surface: brown(ish) green (olivaceous, olive green) | green(ish) brown (olive brown) [th upper surface]: epruinose [th marginal and upper surface] specific structures: absent [th] morphol substructures (eg areoles, lobes, branches) width [mm]: (low) 0.2 (high) 0.5 (max) 0.8 [th] morphol substructures (eg areoles, lobes, branches) upper surface: smooth, plane | rugose, plicate, folded, pustulate, faveolate, wrinkled ascomata: absent | present ascoma: apothecial, apothecioid – hymenial ascoma [mm]: (low) 0.2 (high) 0.8 (max) 1.0 ascoma: sessile, superficial [ascm, if apoth] disc, mazaedium: plane, flat, flattened, expanded | subconvex, slightly convex [ascm, if apoth] disc, mazaedium: black(ish) | red(dish) brown (if pale: orange brown) [ascm, if apoth] subhymenial layers, hypothecium; [if perith] basal excipulum: red(dish) brown (if pale: orange brown) [ascm] paraphyses/-oids: present [ascm] paraphyses/-oid cells width [µm]: (median) 1.5 [ascm] epihymenium, epithecium: black(ish) | brown(ish) black 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 (max) 10.0 [asp] shape: ovoid, ovate [asp] length [µm]: (low) 11.5 (high) 13.5 [asp] width [µm]: (low) 6.5 (high) 8.2 [asp] septa: absent – spore lumen unilocular, monolocular [asp] pigmentation: hyaline, colourless [asp] perispore, epispore: not apparent secondary metabolites: absent primary photobiont: present secondary photobionts (eg in cephalodia): absent primary photobiont: cyanobacterial.

substrate: rock, stones, pebbles – unspecified.