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Stereocaulon alpinum Laurer ex Funck
Family: Stereocaulaceae
[Stereocaulon paschale var. alpinum (Laurer) Mudd,  more]
Stereocaulon alpinum image
Stephen Sharnoff  
Thompson, J., 1984. American Arctic Lichens: The Macrolichens.
Primary thallus disappearing; pseudopodetia dorsiventral or erect, caespitose, firmly attached to the ground, 1-4 cm tall, 0.5-1 (-2) mm thick at the base; the base pale brownish or blackish, sparingly branched; lower part without phyllocladia but with a grayish, whitish, or roseate tomentum; phyllocladia crowded toward the apices, whitish-gray with a bluish tinge or whitish, turning pale dirty yellowish in herbarium, granuliform, or united, somewhat flattened, lobate, 0,5 mm broad, indistinctly stalked, appressed to the pseudopodetium; cephalodia on lower side, hemispherical, grayish-white, 0.3-0.8 mm, partly concealed in the tomentum, containing Nostoc. Central medullary layer of pachydermatous, 3-4 ft, loosely conglutínate, strictly parallel hyphae; exterior hyphae dirty yellowish, gelatinous, pachydermatous, 6-8 µ thick; cortex of phyllocladia 15-25 µ, grayish. Apothecia terminal on the podetia or grouped on the upper branches, immarginate; disk dark brown, 1-1.5 mm broad, convex or irregularly swollen; lower side with the center tomentose, the margin bare; exterior hyphae brownish yellow, gelatinous, to the edge becoming parallel and perpendicular to the surface; hypothecium 35-40 /jl, hyaline; hymenium 40-50 µ (60-70 µ acc. Frey), yellowish, I + blue; paraphyses slightly coherent, 1.7—2.0 µ thick, the tips brownish, capitate, 3-4 µ; asci elongate clavate 50-55 X 9-11 µ; spores 8, cylindrical, with one end narrower, slightly bent or straight, 3 septate 27-38 x 2.5-3 µ. Conidia straight, bacilliform, 5 X 1.5.

Reactions: Central axis KOH—, phyllocladia KOH +yellow, P +yellow, containing atranorin and lobaric acid, /3-sitosterin (Lamb 1977).

This species grows on the ground, especially under a late snow cover. It appears to be circumpolar, arctic-alpine, ranging south to New Hampshire, Colorado, and Washington in North America. It is also reported from the southern hemisphere.