A genus Schizotrema (Graphidaceae) new to China, with a world-wide key

摘要: Based on the specimens collected from Yunnan Province, the lichen genus Schizotrema Mangold &Lumbsch is reported as new to China, with the species S. guadeloupense (Hale) Mangold & Lumbsch. Among Graphidaceae, the genus is characterized by its ascomata with concentrically layered margins composed of carbonized excipular remnants of older hymenia; the proper exciple is fused to indistinctly free, periphysoids are usually present, and the ascospores are transversely septate to muriform. The species also is new to Asia. Notes of other five species in the genus are given, also with ecology and distribution. World-wide key to species of Schizotrema be presence in the present paper. This study provides the basic data for the taxonomy of the family Graphidaceae.