A survey of the section Scapania of the genus Scapania (Scapaniaceae) with description of new species Scapania pseudouliginosa and resurrection of S. gigantea

Morphological, molecular-genetic, and phytogeographic analyses of the type section of the genus Scapania resulted in the description of a new species for science Scapania pseudouliginosa, the resurrection of S. gigantea, and segregation of a new subsection Giganteae, including mainly East Asian taxa with thick- to thin-walled median leaf cells with distinct trigones and a few large oil bodies. The key to species of the section and color photomicrographs of S. gigantea, S. pseudouliginosa and S. sichuanica are provided. Scapania rufidula, S. serrulata, S. sichuanica and S. pseudouliginosa demonstrate morphological parallelism with some species of the sections Compactae, Nemorosae, Stephania, and Curtae, respectively. The distinctions of these species are discussed. The parallelism may have resulted from the similarity of their habitats in different phytogeographic areas.