Unity in diversity: phylogenetics and taxonomy of Rhabdoweisiaceae (Dicranales, Bryophyta)

Abstract

Abstract Molecular phylogenetic reconstructions of Rhabdoweisiaceae based on plastid (trnS-rps4 and trnL-F) and mitochondrial (nad5) DNA sequences and a comprehensive taxon sampling were performed, including 15 out of 16 genera currently attributed to the family, taxa recently found belonging to Rhabdoweisiaceae and expanded outgroups from related families of Dicranidae. The suggested revised delimitation of the family comprises Camptodontium (previously referred to Dicranaceae), three subaquatic species currently classified in Blindia (Seligeriaceae), and Glyphomitrium (previously referred to Ptychomitriaceae, Erpodiaceae or its own family) and Eucamptodon perichaetialis (the type species of the genus, previously referred to Dicnemonaceae). The emended delimitation of Rhabdoweisiaceae thus adds to the already high morphological heterogeneity resulting from the divergent evolution of specialized traits in different lineages of epiphytes and saxicolous hygrophytes. Taxonomic inferences from the phylogenetic analyses include segregation of three new genera, Pseudoblindia (for species currently recognized as Kiaeria falcata, Blindia robusta, B. lewinskyae and B. inundata), Ripariella (for Kiaeria riparia) and Brideliella (for Oncophorus wahlenbergii, O. demetrii and Symblepharis lindigii). Hollia is reinstated for the dicnemonoid Australasian species previously classified in Eucamptodon. Additionally, we propose to merge (1) Oreoweisia, Pocsiella and Pseudohyophila with Cynodontium, and (2) Kiaeria s.s. with Arctoa. Furthermore, we propose to limit Oncophorus to O. virens and O. integerrimus and expand the circumscription of Symblepharis to accommodate O. crispifolius, O. dendrophilus, O. elongatus and O. raui. The generic status and inclusion in Rhabdoweisiaceae are confirmed for Cnestrum and the recently described Notocynodontium, and the exclusion of Amphidium, Dichodontium, Holodontium and Hymenoloma from the family is supported.