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Phaeorrhiza sareptana (Tomin) H. Mayrh. & Poelt
Family: Physciaceae
Phaeorrhiza sareptana image
Thompson, J., 1997. American Arctic Lichens: The Microlichens.
Thallus squamulose, 1-3 mm broad, and long lobes forming hummocks or scattered, flat to swollen, brown or paler to ocher or yellow-green in shade; upper cortex 30-40 μm thick, paraplectenchymatous; lower medulla and underside turning intense violet in KOH, red in P. Apothecia at first partially immersed, soon adnate with a thin thalloid margin which rapidly becomes convex, and with the margin excluded, lecideine; exciple dark; hypothecium hyaline, base sometimes reaching the lower cortical region; hymenium 85-100 μm, inspersed, with red-brown epihymenium; paraphyses 1.5-2 μm, poorly visible, tips 2.5-3.0 μm, brown capitate; spores 8, 2-celled, brown, thin-walled, tips often thickened, center constricted, 17-21 x 7-9 μm.

This species occurs on moss and humus; its ecology is similar to that of P. nimbosa. In North America the collections are from Colorado, Montana, Alberta, Saskatchewan, and in the Northwest Territories from Clyde Inlet on Baffin Island and at Reindeer Station in the Mackenzie River valley.

This species is divided by Mayrhofer and Poelt (1978) into two varieties: var. sareptana with the thallus epruinose, the paraphyses 1.5 μm with the tips 1.5-3 μm, occurring in eastern Europe, and var. sphaerocarpa (Th. Fr.) H. Mayrh. & Poelt with the thallus finely but distinctly pruinose, the paraphyses 2-3 μm and their tips 5-6 μm, known from Norway, the Alps, and North America.