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 Add this item to the list  833374 Original description
   
Remarks (public):Ecology and Distribution: Known only from the Galapagos; fertile specimens have only been collected from rock outcrops in the fog-desert ash fields of the high altitude dry zone of Volcán Cerro Azul; thalli without apothecia have also been found on rock outcrops in the humid zone of Volcán Alcedo, and the upper transition zone of Cerro Asilo de la Paz in Floreana. Notes: This species is similar to L. floridula, but saxicolous and characterized by an exciple that lacks large crystals and an epihymenium without any crystals. Unlike the flattened, angular, pale green areoles of the European Lecanora soralifera (Suza) Räsänen, areoles of L. malagae are strongly convex, swollen and pale gray in color. In addition to usnic acid and zeorin, specimens of L. malagae always contain atranorin. Some of the sterile specimens may also contain additional xanthones (arthothelin and asemone, material cited below). The sterile specimens closely resemble Trapelia coarctata (Turner) M. Choisy, but individual areoles of L. malagae are typically larger, more convex and react C– (or, if xanthones are present C+ yellowish orange, but not reddish). 
Description type:Original description 
Description:Thallus saxicolous, moderately thickened, areolate, areoles swollen, bullate, i.e., ±aggregated in convex clusters and deformed by mutual pressure; surface pale yellowish green to yellowish gray, smooth, matt, epruinose, sorediate; soralia pustulate, convex, initially distinctly delimited, but in older thalli becoming coalescent, then at least in parts covering and thus obscuring the thallus, soredia yellowish to greenish white, mealy to granular, generally brighter in color than the thallus; prothallus absent. Apothecia sparse to ±numerous, circular, 0.1–0.8 mm in diam., sessile, distinctly lecanorine, margin persistent, undulate to crenulate, smooth, epruinose, concolorous with the thallus, rarely disintegrating into soredia, disc ±plane, deep olive brown or blackened, typically obscured by a farinose, whitish grey pruina; hymenium hyaline, not inspersed, epihymenium with a weak, diffuse orange-brown pigment (cf. elachista-brown: dissolving in K, HCl± dull greenish brown, N−; adding K after N causes the formation of c. 1µm fuscous brown granules), additionally in parts discolored also by an aeruginose pigment (cinereorufa-green: intensifying in K, HCl+ bluish green, N+ reddish violet), crystals absent, brown pigment dissolving, aeruginose pigment persistent (±gangaleoides-type); proper exciple thin, indistinct, with few crystals; thalline exciple thick, ecorticate to indistinctly corticate, pale blackish wine-red along the outside, only with minute crystals, soluble in K (allophana-type); subhymenium and hypothecium hyaline; ascospores 8/ascus, simple, ellipsoid, (7.8–)9.5–12.5(–13.7) × (3.9–)4.8–6.5(–6.9) µm (n = 30). Pycnidia not seen. Chemistry: Thallus cortex and apothecial margin P+ yellow, K+ yellow, C-, KC-, UV-; with atranorin [major], usnic acid [major], zeorin [major], often also with SV-1 [minor; derived from photobiont, of no taxonomic value]; two sterile specimens contain arthothelin and asemone, they react C+ yellowish orange, UV+ bright yellow. 
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