| Holotype: Acarospora oreophila K. Knudsen |
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Description: Thallus: squamulose, mostly (1-)3-6 mm across.
squamules: dispersed or contiguous, sometimes overlapping, 1 mm thick, regularly dividing;
upper surface: light to dark brown, but young squamules often whitish gray, dull, smooth but
developing creases, sometimes blackening toward rims, epruinose; cortex: prosoplectenchymatous,
without surface formed of expanded hyphae apices, 90-120 µm thick; syncortex: thin, uneven, 10 µm thick;
eucortex: obscure in water, 80-100 µm thick; upper layer: thin, reddish brown; lower layer: hyaline,
prosoplectenchymatous, derived from hyphae from medulla interrupting algal layer;
algal layer: 150-200 µm thick, upper and lower strata uneven, interrupted with hyphal bundles;
medulla: prosoplectenchymatous, 100+ µm thick; lower surface: reddish brown,
darkening sometimes to black, but sometimes appearing white, corticate, formed from medullary prosoplectenchyma forming
an anticlinal hyaline zone 30-40 µm thick, the outer surface formed from tightly packed apices in pigment hoods;
attachment: stipe; Apothecia: punctiform, 0.1-0.2 µm wide, easily mistaken for
pycnidia, pale brown, up to twenty per squamule; disc: brown, slightly darker than thallus;
parathecium: indistinct; epihymenium: hyaline, packed together in narrowed disc,
15-25 µm thick; hymenium: hyaline, 190-210(-250) µm tall; paraphyses:
c. 1 µm wide, thin-walled, with hyaline apices; subhymenium: 30-35 µm thick,
KI+ blue; asci: narrowly clavate to cylindrical, 180-200 x 18-20 µm, 200+ spored;
ascospores: hyaline, simple, ellipsoid, mostly 5 x 1 µm; pycnidia: not observed;
secondary metabolites: none. |
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Type: USA: California: Riverside County: San Jacinto Mountains, Idyllwild, near Inspiration Point, 33° 43’ 36” N, 116°43’ 03” W, 1602 m, on vertical side of decaying granite boulder with partial daily shade, edge of Pinus jeffreyi forest, Knudsen 3459 (Holotype, UCR; Isotypes, ASU, B, H, hb. Roux, PH, UPS) |
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Image: Janet Good. |
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