Neckera, Forsstroemia and Alleniella (Neckeraceae, Bryophyta) redefined based on phylogenetic analyses

Abstract

Phylogenetic relationships of species within the pleurocarpous moss genus Neckera s.l. (Neckeraceae) are reconstructed based on three genomic regions: the plastid rps4-trnT-trnL-trnF cluster and the rpl16 group II intron, as well as the internal transcribed spacer region of the nuclear ribosomal DNA (ITS1-5.8S-ITS2). The phylogenetic reconstruction suggests numerous taxonomic changes within the Neckeraceae. Two unispecific Asian genera are described as new: Taiwanobryopsis to accommodate Neckera warburgii, and Indoneckera to accommodate Neckera himalayana. Seven of the other “Neckera” species, all distributed in Asia, are transferred to Forsstroemia, and a further four Asian species to Taiwanobryum. Six Southern Hemisphere or tropical species (one from New Zealand, one from Africa, four from South America) are transferred to Alleniella. After these adjustments, Neckera becomes a northern hemisphere, mainly temperate, genus of c. 10 species that are absent from the tropics. It is in this context morphologically characterized by lack of paraphyllia (except N. californica) and an absent or weak costa. Alleniella has two species—the first diverging lineages—in the northern hemisphere, but the rest of the currently 15 species are distributed in the southern hemisphere and most of the species occur in mountain habitats in the tropics; it is however absent from tropical Asia and very scarce in Asia in general. Twelve of the 15 species have paraphyllia, which is the clearest morphological distinction from Neckera. Forsstroemia with 19 species, heavily concentrated in Asia, is the largest genus in the Neckeraceae. Clearly longer and more distinct costa distinguishes the genus from Neckera and Alleniella. Taiwanobryum is a morphologically heterogeneous Asian genus of nine species. Neckera decurrens Broth. is synonymized with Forsstroemia fauriei and Neckera valentiniana Besch. with Alleniella ehrenbergii.