Chaenothecopsis savonica (Räsänen) Tibell
Beih. Nova Hedwigia, 79: 666 1984. Basionym: Mycocalicium savonicum RäsänenLichenotheca Fennica: no. 296 (1947) - Lichenotheca Fennica: no. 296, 1947
Synonyms:
Distribution:
Description: Thallus not evident, not lichenized. Apothecia stalked, pin-like, 0.4-0.8 mm high. Stalk black, 0.03-0.05 mm thick, of periclinally arranged hyphae, pale in central part, brownish to greenish brown in outer part. Capitulum spherical or lenticular, 0.1-0.3 mm across. Excipulum poorly developed in mature ascomata, consisting of a few layers of hyphae and formed as a continuation of the outermost part of the stalk, normally restricted to the base of the capitulum only. Epithecium thin, aeruginose to brownish; mazaedium not present; hypothecium aeruginose to brownish. Asci 8-spored, 28-37 µm long, cylindrical, with a thickened apex penetrated by a narrow canal, formed singly, persisting until the spores are mature, the spores uniseriately arranged. Ascospores 1-celled, pale greenish brown, ellipsoid with rounded ends, 5-7 x 2-2.5 µm, the wall appearing smooth under the light microscope. Pycnidia small, black, the wall consisting of one layer of radially arranged conidiogenous cells, Conidia hyaline, 2-3.5 x c. 1 µm, slightly truncate at the proximal end. Photobiont absent. Spot tests: ascocarps C-, KC-, P-, N-, the greenish pigments reacting K+ yellowish brown. Chemistry: without lichen substances.Note: lichenicolous on the thallus of Chaenotheca-species or on algal colonies, usually on lignum; widespread from the boreal to the temperate zone in the Holarctic region, also recorded from the Southern Hemisphere; with a few scattered records from the Alps, where it is probably more widespread, but certainly not common. To be looked for in Italy.
Andres Saag University of Tartu
