Chaenotheca chrysocephala (Turner ex Ach.) Th.Fr.
*Account prepared by Dr L. Tibell (Uppsala).
Calicium chrysocephalum Turn. ex Ach., Meth. Lich. Suppl.: 15 (1803).
Thallus normally episubstratic, well-developed, granular, intensely yellow, more rarely almost completely immersed and hardly visible. Photobiont: Trebouxia and Stichococcus. Apothecia short, to middle-sized, 0.6-1.3 mm high, 9-22 times as high as width of stalk. Stalk 0.04-0.08 mm diam., with a dense, yellow pruina in upper part, lower part black to pale brown. Capitulum obovoid or broadly obconical, with well-developed excipulum. Excipulum 0.16-0.27 mm diam. Hypothecium broadly obconical with flat or slightly concave upper surface. Lower side of capitulum with a dense yellow pruina. Asci cylindrical, with uniseriate spores, well-stalked, 14-19 × 2.2-3.3 µm, produced singly. Ascospores shortly ellipsoid to almost spherical, 6.2-9.0 × 3.8-4.8 µm, with coarse and irregular ornamentation. Chemistry: The thallus contains vulpinic acid which also occurs as pruina on apothecia. Thallus K-, C-, KC-, Pd.
N: North Auckland, South Auckland, Gisborne, Hawke's Bay, Wellington. S: Nelson, Marlborough, Canterbury, Otago, Southland. Rather common on bark and decorticated stumps, particularly of Nothofagus in shaded and rather humid situations, 15-1300 m.
Cosmopolitan
C. chrysocephala is very widely distributed in the Northern Boreal - Temperate Zones of the Northern Hemisphere.
