Rhizocarpon alpicola (Anzi) Rabenh.

[as "alpicolum"], Flechten Europ. 22: 618 (1861) or Lich. Europ. Exs. 618 (1861) fide Thomson (1997)

Basionym: Lecidea alpicola Hepp, Flechten Europas 151 (1853). nom. illeg. fide Thomson 1997: 522. Buellia alpicola Anzi, Cat. Lich. Sondr.: 90 (1860).


Type locality: Finland, Lapp. Kemensis, Muonio, Olostunturi, 1800, Wahlenberg (UPS - lectotype).

Type locality coordinates: Data lacking.

Molecular barcode: Data lacking.

Description: Lichen. Thallus crustose, large, 5 - 8 - 10 cm in diameter, rarely up to 20 cm in diameter. Areolae close together or widely dispersed, usually separated bly black prothallus strips, 0.4 - 3.0 mm in diameter, 0.2 - 1.5 mm thick, strictly angular and more or less plane, or irregularly angular and slightly convex, or roundish and strongly convex, or spheroid, usually subdivided by numerous cracks into smaller parts, yellowish-green to witish-yellow or bright yellow, surface usually smooth, rarely scabrous, usually matt, rarely glossy, cortex 30 - 50 µ thick, medully white. Apothecia 0.6 - 1.5 mm in diameter, 0.5 - 1.5 mm thick, usually roundish and slightly convex, rarely strictly and plane, with or without a distinct margin, often subdivided by a few cracks into smaller parts, often surrounded by an areola. Cortex cells of the excipulum brownish-red. Subhymenium dark brown, 100 - 200 µm thick. Hymenium 110 - 150 µm thick, colourless, uppermost part brownish-red, apical cells of paraphyses clavate, more or less transparent. Epihymenium more or less indistinct, often with a few small, dark grains. Asci clavate 100 - 130 / 30 - 40 µm, containing 8 spores. Spores uni-sepate, 18 - 32 / 9 - 15 µm. Prothallus often thick and well developed, rarely areolated (Runemark 1956a: 70).

Photobiont: Data lacking.

Chemistry: Cortex cells of the excipulum K+ reddish-violet. Epihymenium K+ reddish to wine-red (Runemark 1956a: 70). - Rhizocarpic acid, psoromic acid, sometimes small amounts of gyrophoric acid. K -, P+ intensely yellow, I- (Runemark 1956a: 70 based on 22 specimens). - Rhizocarpic acid, psoromic acid (Matwiejuk 2010: 108 based on one specimen).

Ecology: On silicious rock. In the Alps on boulders (Feuerer). In Scandinavia on boulders and rocks in the lowland.

Distribution Type: "This species was, until recently, not reported from North America. However, specimens have now also been reported from British Columbia (Noble et al. 1987). .. Its distribution at Jonas Rockslide seems very local - only one patch is known - but it is common at that sampling station" (John 1989: 109).

Note: Index Fungorum is using the authority citation "(Wahlenb.) Rabenh.".
Rhizocarpon alpicola (Anzi) Rabenh. by Matwiejuk (2010: 108), AlpList.