TYPE. SPAIN. CANARY ISLANDS, Tenerife. “Ad corticem Ericae arboreae in insula Teneriffa, loco dicto San Diego, legit. D. Bourgeau.” (Nylander 1860).
Description. Lichenized fungus.
Thallus crustose, continuous, thin, granular, pale to yellowish. Photobiont trebouxioid alga. Ascomata stalked capitulate maezedia, 0.48-0.65 mm tall, epruinose or sometimes with a white pruina of minute crystals on the lower side of the capitulum, maezedium convex, black; exciple brown-black, 0.17-0.27 mm diam.; hypothecium dark brown; stalk shiny black. Asci cylindrical, 41-45 x 5-6 μm with a long stalk; 8-spored, in one row (uniseriate). Ascospores brown, ellipsoid, 2-celled, 10-12 x 5-6 μm; surface minutely uneven.
Chemistry. Thallus UV+ dark orange, K+ dull yellow, C+ orange, KC+ orange-red, Pd–. Some specimens contain arthothelin, thiophanic acid, and thuringione, others arthothelin and thiophanic acid only. Smaller amounts of unidentified xanthones occur. Several specimens contain only traces of unidentified compounds or have no detectable amounts of secondary substances.
Substrate and Habitat. Corticolous on hardwood bark in maritime and mixed hardwood forests.
Distribution. Cosmopolitan, most common in the subtropics; in North Carolina found along the coast and in the Coastal Plain ecoregion.
Nylander, W. (1860) Synopsis Methodica Lichenum Omnium hucusque Cognitorum, Praemissa Introductione Lingua Gallica. 1:141-430 (original description).
Giavarini, V.J. & O.W. Purvis. (2009) Calicium Pers. (1794). Pp. 241-245 in Smith, C.W., A. Aptroot, B.J. Coppins, A. Fletcher, O.L. Gilbert, P.W. James & P.A. Wolseley (eds.). 2009. The Lichens of Great Britain and Ireland. The British Lichen Society, London.