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 Add this item to the list  833377 Original description
   
Remarks (public):Ecology and Distribution: Known only from the Galapagos; common on bark or wood in exposed, sunny habitats of the coastal and dry zone, rarely also in the transition zone, one specimen collected on a fence post in the humid zone. Notes: Specimens of L. pyrrhosporoides with granular, slightly darker soredia and a distinct black hypothallus were previously identified as Pyrrhospora quernea (Dicks.) Körb. in the key to the leprose and leproid lichens of the Galapagos (Bungartz et al. 2013). The chemistry and thalli of the two species are very similar, but several specimens have now been found fertile and reports of Pyrrhospora from the archipelago are therefore erroneous. Apothecial characters suggest that L. pyrrhosporoides belongs to the L. varia-group as it lacks the K+ violet epihymenial anthraquinone granules typical for Pyrrhospora. 
Description type:Original description 
Description:Thallus corticolous or lignicolous, leproid (see Bungartz et al. 2013), almost entirely composed of coarse, granular soredia, which develop on the surface of a thin ± contiguous, whitish to almost transparent, film-like prothallus, delimited along the margin by a conspicuous, black prothalline line; granules pseudocorticate, yellowish green to pale greenish beige, surface sometimes discolored, tinged bluish black by an aeruginose pigment, K+ blackish green (30–)44–65(–100) µm in diam., irregularly ±aggregating], individual granules either scattered, in isolated clusters (c. 300–500 µm in diam.), or in well developed thalli packed into a thick, secondarily rimose-areolate crust. Apothecia absent or sparse, rarely numerous, if present typically ±aggregated in small groups and often, ±deformed by mutual pressure, 0.2–0.6(–0.8) µm in diam, adnate to sessile, biatorine, proper margin thin, soon excluded, but frequently surrounded by a secondary, false thalline margin formed from a few to many thalline granules, disc plane to ±convex, pale brown to beige, increasingly discolored with age, olivaceous to blackened, covered by a coarse, hyaline pruina; hymenium hyaline, not inspersed; epihymenium with small orange brown granules, soluble in K (but unlike the anthraquinone granules of P. quernea not turning purple!), lacking distinct crystals, fuscous brown (elachista-brown: dissolving in K, HCl± dull greenish, N−), occasionally in parts or entirely discolored by a diffuse aeruginose pigment (cinereorufa-green: intensifying in K, HCl+ bluish green, N+ reddish violet); proper exciple distinct, hyaline within, outer part concolorous with the epihymenium and covered with small orange brown granules soluble in K, granules at the base of the exciple often very abundant, often ±radiating from the lower inner to the lower outer part of the exciple; thalline exciple absent; subhymenium and hypothecium hyaline; asci Lecanora-type, ascospores 8/ascus, colorless, simple, broadly ellipsoid, (8.0−)10.3−11.4(−12.5)  (3.5−)4.4−7.8(−9.5) µm (n = 30). Pycnidia immersed, ostiole brown, wall hyaline; conidia filiform, 25−32  c. 1−1.2 µm (n = 15). Chemistry: Thallus cortex P+ yellow, rarely P–, K+ yellow, rarely K–, KC+ orange, C+ orange, UV+ deep red; with ±atranorin [major], thiophanic acid [major], arthothelin [major], ±3-O-methylthiophanic acid [minor], ±4-chloronorlichexanthone [minor, trace or absent], ±5-chloronorlichexanthone [minor, trace or absent], ±4,5-dichloronorlichexanthone [trace], ±lichexanthone [trace]. 
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