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Verrucaria adelminienii Zschacke
Family: Verrucariaceae
Verrucaria adelminienii image
Othmar Breuss  
Thallus: evanescent to irregularly rimose with delicate cracks, less than 0.1 mm thick, lacking a prothallus surface: white or greenish white, dull, subfarinose anatomy: upper cortex indiscernible, algal layer 50-100 µm thick, with algal cells 7-12 µm wide, mycobiont portion subparaplectenchymatous, with substrate particles; alga-free medulla: white, obscured by substrate grains and crystals, grading into the decomposed rock surface Perithecia: semi-immersed, hemispherically prominent; exciple: sub-globose, 0.22-0.26 mm wide, pale brown to blackish; involucrellum: completely enveloping the exciple, 30-50 µm thick, brown-black, at the base somewhat paler and ±patchily pigmented; periphyses 25-30 µm long, simple asci: clavate, 8-spored ascospores: hyaline, simple, ellipsoid ,18-23 x 8-10 µm Pycnidia: unknown Spot tests: all negative Secondary metabolites: none detected. Substrate and ecology: semi-endolithic to thinly epilithic, on or in limestone and calciferous sandstone World distribution: Europe and western North America Sonoran distribution: collected once in southern California (Santa Rosa Island). Notes: Morphologically, Verrucaria adelminienii resembles V. muralis, from which it differs in having an involucrellum that completely encloses the exciple though basally often patchily developed when examined in thin section.