Mycena section Sacchariferae: three new species with basal discs from China

This current study presents three novel Mycena species that grow exclusively on specific substrata in southern China, including Castanea mollissima fruits, Fagaceae leaves and Lauraceae twigs or leaves. Mycena castaneicola belongs to Mycena section Sacchariferae stirps Amparoina, because its stipe has a prominent basal disc and it has cherocytes, acanthocysts and caulocystidia covered with spinules. The two other new Mycena species belong to M. section Sacchariferae stirps Adscendens, because of their basal disc characteristics, lack of cherocytes on the pileal surface and the presence of smooth caulocystidia. Mycena hyalinostipitata is characterised by a hyaline stipe, two types of acanthocysts and fusiform caulocystidia. Mycena substylobates can be easily distinguished by its obovoid acanthocysts and irregularly shaped caulocystidia. Detailed descriptions, line drawings and a discussion of morphological characteristics are provided herein. In addition to morphological comparisons with related taxa, phylogenetic analyses of internal transcribed spacer (ITS) nrDNA sequence data were conducted. Maximum likelihood and Bayesian inference analyses of the ITS dataset confirmed the morphology-based classification.