Phylogeny based on 16S rRNA sequence and morphology of selected mosses of Mount Abu, Rajasthan (India)

The phylogenetic relationship of mosses remains an area of deep uncertainty, with different arrangements of order, class and families being found in studies that examined various subsets of genes and taxa. Herein we performed separate and combined analyses of morphological and molecular data sets to explore the controversial phylogenies of the moss lineages. We examined data set that comprises of ten moss species and four outgroup taxa drawn from liverworts. The molecular data contain nucleotide sequences derived from plastid DNA regions, i.e. partial 16S rRNA sequences and the morphological data included 18 characters derived from own observations and published literature. Congruence between the two data sets was investigated by computing several indices. The morphological data set contains poor phylogenetic signals. The results suggest that 1) the mosses, including Sphagnum and Takakia, are monophyletic, 2) Sphagnum and Takakia are placed together and sister to remaining mosses, 3) mosses with nematodontous peristomes are paraphyletic and basal to arthrodontous mosses, 4) mosses with diplolepideous alternate peristomes form a monophyletic group, 5) pleurocarpous mosses derived from acrocarpous mosses. Despite of the incongruence of morphological and molecular data sets, the combined data set analysis provided improved resolution of higher level relationship.