Phylogeny of Schistidium (Bryophyta, Grimmiaceae) was studied by comparing the nucleotide sequences of internal transcribed spacers ITS1-2 of nuclear rDNA and the trnT-trnD region of chloroplast DNA. Phylogenetic trees constructed based on nuclear and chloroplast sequences were consistent, comprising a basal grade and two large clades. Morphological characteristics specific for these clades were described. Secondary structures of ITS1 and ITS2 Schistidium species were modeled using thermodynamic criteria. Four different structures of the longest ITS1 hairpin were identified. These results were used to analyze possible paths of Schistidium evolution. Characteristics of the ITS2 secondary structure support the two major clades recognized in the phylogenetic trees.
The taxonomic diversity center of Schistochilopsis is in East Asia, where the genus also shows the highest genetic diversity and morphological plasticity. The integrative survey of Schistochilopsis in East Asia was the main goal of the present account. Plant materials were obtained from recent collections made by authors in various parts of amphi-Pacific Asia; several types of specimens were also studied. The study includes phylogenetic reconstructions from nuclear ITS1,2, chloroplast trnL and trnG sequences, and anatomo-morphological, biogeographical, and taxonomical analyses. As a result, it was concluded that S. obscura should be transferred to Lophozia s. str. and S. grandiretis to the newly described genus Protochilopsis. Lophozia boliviensis was found to be part of the Andean–Sino-Himalayan taxon belonging to Schistochilopsis. The species status of S. hyperarctica and S. opacifolia was not confirmed. Substantial genetic variation is observed within S. incisa with possible cryptic sympatric distributed entities. The taxonomical section of the paper provides a discussion on the status, distinctive morphological traits, distribution, and ecology supplemented with the morphological description for poorly understood taxa. In the vast majority of cases, the illustrations and photographs made from the types and living material are provided.