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The mitochondrial 16S rDNA sequences of 40 species of cheilostome bryozoans including those of 24 species newly determined were used to reconstruct the phylogenetic tree using neighboring-joining and maximum-parsimony methods. By applying molecular clock technique on the basis of the appropriate phylogeny and the fossil record, the divergence times of the two main cheilostome groups, Anasca and Ascophora sensu stricto, were estimated. The results show that the molecular phylogeny of the higher taxonomic groups (superfamilies and higher taxa) of cheilostome bryozoans is mostly in conflict with the morphology-based phylogenetic trees; the divergence of the extant groups of Anasca and those of Ascophora sensu stricto is estimated to have happened about 263 Ma (permian Guadalupian Epoch) and 183 Ma (Early Jurassic), respectively.

The early evolutionary pattern and molecular adaptation mechanism of alpine Parnassius butterflies to high altitudes in Qinghai–Tibet Plateau are poorly understood up to now, due to difficulties in sampling, limited sequence data, and time calibration issues. Here, we present large-scale transcriptomic datasets of eight representative Parnassius species to reveal the phylogenetic timescale and potential genetic basis for high-altitude adaptation with multiple analytic strategies using 476 orthologous genes. Our phylogenetic results strongly supported that the subgenus Parnassius formed a well-resolved basal clade, and the subgenera Tadumia and Kailasius were closely related in the phylogenetic trees. In addition, molecular dating analyses showed that the Parnassius began to diverge at about 13.0 to 14.3 million years ago (middle Miocene), correlated with their hostplant’s spatiotemporal distributions, as well as geological and palaeoenvironmental changes of the Qinghai–Tibet Plateau. Moreover, the accelerated evolutionary rate, candidate positively selected genes and their potentially functional changes were detected, probably contributed to the high-altitude adaptation of Parnassius species. Overall, our study provided some new insights into the spatiotemporally evolutionary pattern and high altitude adaptation of Parnassius butterflies from the extrinsic and intrinsic view, which will help to address evolution, biodiversity, and conservation questions concerning Parnassius and other butterfly species.

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Phymatopteris Pic. Serm., a derived polypodiaceous fern, is one of the many fern genera that still suffer from nomenclatural confusion. Its generic circumscription and phylogenetic relationships with other selligueoid ferns have been controversial, and its geographic origin, whether in the Himalayan region of continental Asia or in Malay Archipelago, is still unknown. A phylogeny of all selligueoid ferns based on 4 cpDNA (rbcL, trnL-F, rps4 and rps4-trnS) regions indicates that Phymatopteris is not monophyletic. Phymatopteris species are distributed in 5 well-supported clades that can be distinguished with frond-shape and frond-margin characters. All early-divergent species are from the Malaysian Archipelago, while the remaining species are all from the Himalayan region and form a recently diverged group that is largely unresolved, most likely having resulted from an explosive radiation. Divergence-time estimation suggests that the first diversification of selligueoid ferns occurred at ca. 27 Ma in the Malaysian Archipelago, followed by migration into the Himalayan region around 20 Ma. The radiation of the Himalayan species occurred mostly within the last 20 million years, within the period of recent major uplifts of the Qinghai-Tibetan Plateau (between the early Miocene and the Pleistocene) and late-Cenozoic global cooling. Our evidence leads us to propose that the Malaysian Archipelago is the ancestral area for Phymatopteris.

The origin and dispersal history of the large butterfly subfamily Nymphalinae are not fully understood, due to internal phylogenetic and time calibration issues. We conducted phylogenetic and dating analyses using mitochondrial and nuclear genes of biogeographically diverse groups of the Nymphalinae in order to resolve some controversial relationships and the paleobiogeographic pattern of the subfamily. Our results support the sister relationship of Vanessa (Tribe Nymphalini) and the Nymphalis-group, and the grouping of the three old-world genera (Rhinopalpa, Kallimoides and Vanessula) within Tribe Victorinini. Molecular dating analyses invoking two additional calibrations under the butterfly-host plant coevolutionary scenarios result in a relatively deeper divergence of the subfamily's two major clades (Nymphalini and the Kallimoids), compatible with the Cretaceous floral turnover scenario during the so-called Cretaceous Terrestrial Revolution. Phylobiogeographic analyses reveal that the Oriental region is probably the center of early divergences for Nymphalinae after the Cretaceous-Paleogene (K-Pg) mass extinction, followed by repeated dispersals into the rest of the Old World and the New World during various periods beginning in Eocene. The biogeographic history indicates that temperature changes and host-plant diversification may have facilitated the dispersals of this butterfly subfamily, with accelerated global colonization during the middle to late Miocene.The subfamily Nymphalinae consists of the tribes Nymphalini, Melitaeini, Kallimini, Victorinini, Junoniini, and probably the Coeini 1 . Previous studies, based on various gene sequences of taxa with several missing genera, resulted in weakly supported and unstable trees that need clarification 1-3 . For example, the clade comprising the genera Vanessa and Hypanartia was unstable; the basal relationships of the kallimoid clade and the sister relationship of Kallimini and Melitaeini were poorly resolved; the phylogenetic positions of the three monotypic genera (Kallimoides, Rhinopalpa and Vanessula) were also uncertain.Within Nymphalinae, the tree topology and molecular dating results may be significantly affected by taxon sampling, time-calibration points and parameter models [2][3][4][5] . The ages of diversification of major lineages and the influenced historical biogeography of this butterfly subfamily were still fraught with uncertainties, due to computational constraints, limited exemplar species, scarce and relatively young fossils, and potentially underestimated ages of host plants as maximum prior time constraints in previous studies [1][2][3] . Butterflies and their host plants are often found to coevolve and phylogenetically conserved [6][7][8][9][10] . Previous studies indicate that butterfly lineages with inferred major historical host shifts showed significant diversification accelerations. Some key plant groups (e.g., Acanthaceae, Asteraceae, Brassicales) appear to have been used by butterfly as larval hosts in close evolutionary time to th...