Microcalicium Vain.
* Account prepared by Dr L. Tibell (Uppsala).
Parasitic on lichens and on colonies of free-living algae, or living saprophytically. Apothecia stalked or sessile, with a greenish mazaedium. Asci formed in chains without hook-formation, broadly ellipsoid when mature. Ascospores in asci simple. When the asci have disintegrated the spores continue to mature in the mazaedium, where they increase considerably in volume, septation takes place and the ornamentation of spirally arranged ridges forms. Mature spores 1-3-septate. Pycnidia with conidia formed from phialides.
Key
The genus was recently revised by Tibell [ Bot. Notiser 131: 229-246 (1978)], and contains four species, two occurring in cold temperate to temperate areas of both hemispheres, while one is restricted to the Southern Hemisphere, and one to the Northern Hemisphere.
