Further observations on the lichen genus Megalaria in Tasmania: some species with blue-green apothecial pigments

摘要

Four species of the lichenised Ascomycete genus Megalaria are treated, namely the cosmopolitan Megalaria grossa, the two new species, M. hafellneriana (from Tasmania and Victoria) and M. planocarpa (endemic to Tasmania), and M. subintermixta (new combination), which is recorded for Tasmania, Victoria and New South Wales. Catillaria grossulina is reduced to synonymy with Megalaria grossa. The species are described and illustrated, and their affmities with other taxa are discussed. The structure and pigmentation of the proper excipulum, the anatomy of the asci, and ascospore size are seen as the most important characters in the delimitation of Megalaria species whereas substrate and thallus characters can be ambiguous. A provisional key to Tasmanian species is provided.