Stereocaulon botryosum

Stereocaulon botryosum, from here.

Belongs within: Stereocaulaceae.

Stereocaulon botryosum is a species of lichen found in northern Eurasia and North America.

Characters (from Frey 1933, translated using Google Translate; all errors my own): Dusty thallus often present, both among strongly developed podetia as well as particularly at the edge of encrusted forms. Podetia in dense patches, gradating at the lower, younger edges into a crusty thallus. Entire surface usually smooth(?). Individual well-developed podetia 2.5(-3) cm high, very firmly stuck to the rock, often radiating from a common center, but often growing side by side like grass. Larger podetia often thickened at the base to 4 mm, brown to brown-black, whitish upwards, with numerous tree-like branches, the outermost strong podetien usually very cauliflower-like. Phyllocladia slightly bluish or grayish white, clustered very tightly, warty, rarely slightly elongated scaly, or widened, and then slightly, usually 0.2 to 0.3 mm wide. Apothecia occasionally on extended branches, otherwise somewhat outstanding, terminal, often grouped together, larger apothecia divided into many sections(?), dark brown, first flat and surrounded by a fine, soon vanishing edge, 1.5-3 mm wide. Hyphae of the central strand (2-)3-4(-5) μm thick, fairly tightly parallel, more or less dense, often somewhat bonded; those against the base of podetia finer, smoother, less glued, with thin walls; those against the points of the podetia thick, rough and more glued, rather thich-walled. Average area of ​​the cavities are, however, more than half of the entire thickness. The external hyphae form a fairly clearly defined cylinder, 30-50 μm thick, the outermost hyphae 7-10 μm thick, thick-walled. Felt to 60 μm thick. Reaction KOH-. Cortex of phyllocladia contiguous, about 15 μm thick, often thinner, hyphae 3.5 μm thick, dimly discernible. Gonidia in layer about 50 μm thick, 7-10 μm in size, Cystococcus. Cephalodia hidden in tomentum or grape-like and warty, less than 0.5 mm, purple, or whitish dusted, often on the surface of the pad and then larger, up to 2.5 mm wide. Mostly containing Stigonema, but also Nostoc. Underside of apothecium covered with a dense felt, which often reaches up to the edge of the disc, not uncommonly small phyllocladia are woven into this tomentum. In places, this felt is dense and forms a loose palisade. However, elsewhere this felt is very loose, consisting of highly branched and confused hyphae, to 150 μm thick. Where the felt is designed more like a palisade, the hyphae are up to 8 μm thick and moderately thick-walled; in the loose, but thicker parts of the tomentum, hyphae are only 4-5 μm and moderately thin-walled. Central strand breaking off suddenly under the central cone; packing hyphae of the latter tightly glued, thick-walled, indistinct, only the 2-2.5 μm wide lumina of the cells clearly visible. Central cone granulated. Hypothecium quite significantly confined, 40 μm high; parathecium indistinct; hymenium 60-65 μm high, the hyphae 2-1.5 μ thick, J colors only the asci blue, not the hymenial gelatine. Paraphyses 1-1.5 μm thick, mostly loose, head cells to 4.5 μ thick, yellow-brown, asci 50-55 × 8-10 μm, spores often poorly developed, 20-31 × 4-5 μm. Pycnidia often numerous, 0.09 to 0.12 mm, brown spots on the tips of the phyllocladia, wall pale brown, colorless in the lower part. Conidia 5-7 × 0.6-0.8 μ, cylindrical.

<==Stereocaulon botryosum Acharius 1810 (see below for synonymy) F33
    |  i. s.: S. b. f. confluens (Magnusson 1926) Frey 1933 F33
    |         S. b. f. congestum (Magnusson 1926) Frey 1933 F33
    |         S. b. f. depressum (Magnusson 1926) Frey 1933 F33
    |         S. b. f. dissolutum (Magnusson) Frey 1933 [=S. fastigiatum f. dissolutum Magnusson 1926] F33
    |         S. b. f. finmarkicum (Magnusson) Frey 1933 F33
    |         S. b. f. globuliferum (Magnusson 1926) Frey 1933 F33
    |         S. b. f. irregulare (Magnusson 1926) Frey 1933 F33
    |         S. b. f. simplicior (Magnusson 1926) Frey 1933 F33
    |         S. b. f. spathuliferum (Vainio) Frey 1933 [=S. spathuliferum Vainio 1909] F33
    |--S. b. f. botryosum F33
    `--S. b. var. subincrustatum Frey 1933 F33

Stereocaulon botryosum Acharius 1810 [incl. S. fastigiatum Anzi 1860, S. evolutum f. fastigiatum (Anzi) Anders 1928, S. evolutum var. fastigiatum (Anzi) Fries 1874, S. paschale var. pulvinatum Schaerer 1833, S. corallinum var. pulvinatum (Schaerer) Schaerer 1850] F33

*Type species of generic name indicated

REFERENCES

[F33] Frey, E. 1933. Cladoniaceae (unter Ausschluss der Gattung Cladonia), Umbilicariaceae. In Die Flechten (Dr. L. Rabenhorst’s Kryptogamenflora von Deutschland, Österreich und der Schweiz vol. 9) sect. 4, part 1. Akademische Verlagsgesellschaft M. B. H.: Leipzig (reprinted 1971. Johnson Reprint Corporation: New York).