Pulvinora cavicola Mazur & Sliwa 2025, comb. nov.

Pulvinora cavicola (Creveld) Mazur & Śliwa comb. nov. Fig. 2 Lecanora cavicola Creveld, Bibliotheca Lichenologica 17: 273 (1981). Basionym. Type. Norway • ‘ SE slope Vesl. Nystuguhӧ; Sӧr Trӧndelag, 62°18' NBr, 9°34'OL, d. d. juli 1976, Leg. M. Arnolds-Creveld, Det.: MAC’ (isotype GZU 000291029!). Description. Thallus creamy to pale greenish, inconspicuous and strongly reduced, or thick, verruculose, areolate to squamulose. Areoles convex, bullate, and irregular, often with craterous, creamy, or light-orange soredia dispersed on the whole thallus, 0.4–3 μm in diam. Prothallus present, black and film-like or pale blue, green, or white and filamentous. Apothecia absent or scarce, sessile, ca. 0.3–0.8 mm in diam. Apothecium margin lecanorine, continuous, and soon excluded. Disc convex, sandy in color. Amphithecium, measured in the middle of thalline margin, is 115 μm wide. Algae are present and scarce. Amphithecial cortex gelatinous, ca. 20 μm. Parathecium hyaline. Epihymenium olive-brown, HCl –, K + (discolored), and N + (red-orange). Hymenium hyaline, ca. 70 μm high. Subhymenium not visible. Hypothecium hyaline, up to 125 μm high. Any granules and crystals are not visible in the ascomata. Paraphyses are simple, slender, and unthickened — the apical and basal parts measure 2.5 μm. Asci clavate, 8 - spored. Spores hyaline, simple, broadly ellipsoid; 9.0 – (9.5) – 10.0 × 5.0 – (5.5) – 6.0 μm (N = 40), L / W ratio = 1.8 μm. Pycnidia not observed. Chemistry. Atranorin, alectorialic acid, and thamnolic acid (for specimens A. Flakus 29582 and 29567) or, perlatolic, alectorialic, and thamnolic acids present (A. Flakus 29569). Specimens examined. Bolivia • Dept. La Paz, Prov. Bautista Saavedra, Área Natural de Manejo Integrado Nacional APOLOBAMBA – protected area, road Pelechuco to Charazani, close to Apacheta, elev. 4262 m, 14°48'27"S, 69°08'05"W, 2017, A. Flakus 29582, 29567, 29569 (KRAM, LPB). Exsiccate seen. Weber, Lich. Exsicc. COLO 135, identified by Poelt, pro parte (as Lecanora pringlei; cf. Weber 2008) in KRAM. Reference materials have also been seen from Poland, Tatra Mts., and Bolivia (KRAM; for specimen list see Flakus 2014 and Śliwa et al. 2012). Notes. Detailed descriptions of the species (under the name L. cavicola) are also presented in Poelt and Leuckert (1984) and Ryan et al. (2004). The authors have consistently stated that it occupies an isolated position within Lecanora, which was finally confirmed in this study by demonstrating L. cavicola placement in the recently established genus Pulvinora. The species was described from Norway at the end of the previous century (Creveld 1981) and subsequently reported from various countries in Europe and from other continents. The species appears to be unique among crustose lecanoroid lichens, and its identity can be easily recognized by the pinkish soralia (reflecting alectorialic acid content) in stored herbarium material. The known variation of the species’ secondary chemistry and its geographical range was discussed by Śliwa et al. (2012) while reporting it for the first time from South America, where it was discovered in a few Bolivian provinces. The species produces atranorin and alectorialic acid and, according to the original description, also thamnolic acid (Creveld 1981). However, chemotypes lacking thamnolic acid are commonly reported, and on the other hand, protocetraric acid complex was recorded in addition to atranorin and alectorialic acid (Śliwa et al. 2012). Pulvinora cavicola occurs on hard siliceous rocks in alpine areas. Although it is widespread, it is a rare species (Ryan et al. 2004).