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Relict lineages are an important component of biodiversity, but it is unclear under what circumstances these groups persist. A potential example of such a group is the Alseuosmineae (Asterales) of Oceania. This clade contains the three small families – Alseuosmiaceae, Argophyllaceae and Phellinaceae. The clade has highest diversity in New Caledonia, where there are extensive ultramafic substrates, creating an extreme edaphic environment. Using several lines of evidence we aimed to show that Alseuosmineae qualify as a relict lineage, with specialised adaptations for ultramafic substrates. Molecular phylogenetic and dating analyses were carried out on representatives from all Alseuosmineae genera. Metal concentration in 33 out of 44 Alseuosmineae species was measured in herbarium specimens with X-ray fluorescence spectrometry. Dating analyses indicated that Alseuosmineae began diversifying about 75–80 million years ago, and had much slower net diversification rates than other Asterales groups. One-third of the species occur on ultramafic substrates in New Caledonia. Six are categorised as nickel hyperaccumulators, and two as manganese hyperaccumulators. Extinction was probably paramount in the history of Alseuosmineae, especially for continental species. We postulate that their adaptation to ultramafic substrates and metal accumulation may have contributed to their survival until today. [ABSTRACT FROM AUTHOR]

Sanguisorba is a small genus which consists of about 15 species widely distributed in North America and Eurasia. Previous studies on Sanguisorba are useful for understanding its phylogeny and chloroplast (cp) genome evolution, however, the cp genome resources of Sanguisorba are still limited, and the phylogeny and molecular dating for Sanguisorba and its relatives still need to be further explored. Here, we report four cp genomes of Sanguisorba and conduct comparative analysis of these four Sanguisorba cp genomes plus five previously published ones. The nine cp genomes have a typical quadripartite structure with a total length of 154 282–155 730 bp and their gene content, gene structure and gene order are relatively conserved. Analysis of single copy (SC)/inverted repeat (IR) boundaries shows only very slight boundary differences among the Sanguisorba cp genomes. Eight variation hotspots were screened as excellent candidate markers for future studies in Sanguisorba. Phylogenetic analysis indicated that Sanguisorba is monophyletic and a member of Agrimonieae subtribe Sanguisorbinae. Within Sanguisorba, S. filiformis is the sister group of the six other taxa in the present sampling. Estimation of divergence times indicates that the subtribes Agrimoniinae and Sanguisorbinae diverged at the transition between the Oligocene and the Miocene, and divergent times of Agrimonieae genera ranged from the late Miocene to the Middle Pleistocene. This study enriches the available cp genome resources of Sanguisorba, and it is of great significance to further study of the phylogeny and evolution of Sanguisorba and its relatives. [ABSTRACT FROM AUTHOR]

Genista etnensis is a remarkable and well-known tree endemic to Sicily, Sardinia, and Corsica (Mediterranean Basin). Nevertheless, its morphological variability and its native status throughout its range need to be further investigated. In this study, we aim to clarify some aspects of this infraspecific variability by molecular means. Sequences of one nuclear and five plastid markers were analyzed under maximum parsimony by using TCS software. Plastid data were also time-calibrated under a Bayesian Inference framework. Plastid data revealed strong isolation between the populations from the Cyrno-Sardinian biogeographical province, which are also the most diverse and presumably the most archaic, and those from Sicily and Southern Italy (in this latter area, the species is naturalized). The calibration analysis indicates that the last common ancestor between G. etnensis and its sister group G. fasselata dates back to the middle Pliocene or slightly later, when sclerophyllous Mediterranean vegetation spread, whereas G. etnensis itself might have originated in the middle Pleistocene. The current, rather unusual distribution of G. etnensis could be explained by long-range seed dispersal from the western part of the range or by anthropogenic introduction into Sicily, with extinctions of transported haplotypes in the region of origin. Interestingly, the Vesuvius population, introduced from Sicily in recent times and locally naturalized, shows private genotypes, and was richer in both genotypes and haplotypes than the Sicilian ones. [ABSTRACT FROM AUTHOR]

Native American hawkweeds are mainly mountainous species that are distributed all over the New World. They are severely understudied with respect to their origin, colonization of the vast distribution area, and species relationships. Here, we attempt to reconstruct the evolutionary history of the group by applying seven molecular markers (plastid, nuclear ribosomal and low-copy genes). Phylogenetic analyses revealed that Chionoracium is a subgenus of the mainly Eurasian genus Hieracium, which originated from eastern European hawkweeds about 1.58–2.24 million years ago. Plastid DNA suggested a single origin of all Chionoracium species. They colonized the New World via Beringia and formed several distinct lineages in North America. Via one Central American lineage, the group colonized South America and radiated into more than a hundred species within about 0.8 million years, long after the closure of the Isthmus of Panama and the most recent uplift of the Andes. Despite some incongruences shown by different markers, most of them revealed the same crown groups of closely related taxa, which were, however, largely in conflict with traditional sectional classifications. We provide a basic framework for further elucidation of speciation patterns. A thorough taxonomic revision of Hieracium subgen. Chionoracium is recommended. [ABSTRACT FROM AUTHOR]

The Euro-Siberian steppes have experienced large-scale range fluctuations due to the climatic changes of the Pleistocene that may have also fuelled reshuffling of past steppe vegetation. These species-rich steppe grasslands were much more widespread during glacials and contracted during interglacials, a dynamic which should also be reflected by the evolutionary history of their biota. Astragalus austriacus is a widespread steppe species with European-western Siberian distribution and an ideal model to study the florogenesis of the Euro-Siberian steppes. Here, we inferred the phylogeography of A. austriacus based on genotyping-by-sequencing (GBS) data from populations sampled from the western edge of the Pannonian region across the Pontic region to the western Siberian region. Additionally, we applied molecular dating using single gene sequence data (ycf 1, mat K and ITS). We outline an evolutionary scenario in which intraspecific diversification occurred in the eastern part of Europe during the later Pleistocene (0.48–0.24 Ma). From there, the species expanded both eastwards and westwards, likely during a cold period, which is reflected by two main lineages within A. austriacus that today occur in the Pannonian sensu lato and in the Pontic/south-western Siberian regions, respectively. Demographic modelling supported such a scenario and showed that population sizes were larger during the last cold stage and contracted postglacially. Within the Pannonian sensu lato region, strong substructure was detected, likely as a result of repeated disintegration of the continuous cold-stage steppes in Europe. Finally, our results are in line with evolutionary scenarios suggested for other steppe species such as Adonis vernalis. • Astragalus austriacus is a member of the highly diverse and derived Hypoglottis clade. • A. austriacus lineages of the main distribution area evolved in the later Pleistocene in the Pontic-Pannonian region. • A Pannonian and a Pontic/Siberian lineage of A. austriacus evolved independently. • Populations of A. austriacus declined after the end of the last glacial period. [ABSTRACT FROM AUTHOR]

Abstract Background Divergence time estimation is fundamental to understanding many aspects of the evolution of organisms, such as character evolution, diversification, and biogeography. With the development of sequence technology, improved analytical methods, and knowledge of fossils for calibration, it is possible to obtain robust molecular dating results. However, while phylogenomic datasets show great promise in phylogenetic estimation, the best ways to leverage the large amounts of data for divergence time estimation has not been well explored. A potential solution is to focus on a subset of data for divergence time estimation, which can significantly reduce the computational burdens and avoid problems with data heterogeneity that may bias results. Results In this study, we obtained thousands of ultraconserved elements (UCEs) from 130 extant galliform taxa, including representatives of all genera, to determine the divergence times throughout galliform history. We tested the effects of different “gene shopping” schemes on divergence time estimation using a carefully, and previously validated, set of fossils. Our results found commonly used clock-like schemes may not be suitable for UCE dating (or other data types) where some loci have little information. We suggest use of partitioning (e.g., PartitionFinder) and selection of tree-like partitions may be good strategies to select a subset of data for divergence time estimation from UCEs. Our galliform time tree is largely consistent with other molecular clock studies of mitochondrial and nuclear loci. With our increased taxon sampling, a well-resolved topology, carefully vetted fossil calibrations, and suitable molecular dating methods, we obtained a high quality galliform time tree. Conclusions We provide a robust galliform backbone time tree that can be combined with more fossil records to further facilitate our understanding of the evolution of Galliformes and can be used as a resource for comparative and biogeographic studies in this group.

Arecaceae is a species-rich clade of Arecales, while also being regarded as a morphologically diverse angiosperm family with numerous species having significant economic, medicinal, and ornamental value. Although in-depth studies focused on the chloroplast structure of Arecaceae, as well as inferring phylogenetic relationships using gene fragments, have been reported in recent years, a comprehensive analysis of the chloroplast structure of Arecaceae is still needed. Here we perform a comprehensive analysis of the structural features of the chloroplast genome of Arecaceae, compare the variability of gene sequences, infer phylogenetic relationships, estimate species divergence times, and reconstruct ancestral morphological traits. In this study, 74 chloroplast genomes of Arecaceae were obtained, covering five subfamilies. The results show that all chloroplast genomes possess a typical tetrad structure ranging in size between 153,806-160,122 bp, with a total of 130-137 genes, including 76-82 protein-coding genes, 29-32 tRNA genes, and 4 rRNA genes. Additionally, the total GC content was between 36.9-37.7%. Analysis of the SC/IR boundary indicated that the IR region underwent expansion or contraction. Phylogenetic relationships indicate that all five subfamilies in Arecaceae are monophyletic and that Ceroxyloideae and Arecoideae are sister groups (BS/PP = 100/1). The results of molecular dating indicate that the age of the crown group of Arecaceae is likely to be 96.60 [84.90-107.60] Ma, while the age of the stem group is 102.40 [93.44-111.17] Ma. Reconstruction of ancestral traits indicate that the ancestral characteristics of the family include monoecious plants, one seed, six stamens, and a smooth pericarp. [ABSTRACT FROM AUTHOR]

Austrocarausius Brock, 2000 is a stick insect (Phasmatodea: Lonchodidae) genus containing two species restricted to the tropical rainforests of northern Queensland. Recent specimen collections between the two species' type localities, Lizard Island and Rockhampton, have suggested that Austrocarausius might represent more than the two nominal species. Here, we apply morphological and molecular analyses to revise the taxonomy of this genus. Using both field-collected and historic museum samples, we developed morphological species hypotheses and descriptions. Genetic sequencing of mitochondrial COI and 16S were undertaken for species delimitation and phylogenetic analysis, including an estimate of the evolutionary timescale of the genus. Based on these results, we propose nine new Austrocarausius species, increasing the number of species in the genus to eleven: A. nigropunctatus (Kirby, 1896), A. mercurius (Stål, 1877), A. coronatus sp. nov., A. decorus sp. nov., A. eirmosus sp. nov., A. gasterbulla sp. nov., A. tuberosus sp. nov., A. macropunctatus sp. nov., A. truncatus sp. nov. A. waiben sp. nov. and A. walkeri sp. nov. Our results suggest Austrocarausius species diversified over the last c. 25–70 Ma, resulting in the now endemic distributions in the tropical rainforests of the central and northern Queensland coasts. This is the first integrative systematic study of an Australian phasmid genus, combining morphological, molecular and biogeographical methods. Additional species of Austrocarausius likely remain undescribed as can be inferred from methodical sampling of rainforest patches along the Queensland coast. The decline of tropical rainforests in Queensland during the Miocene–Pliocene era is likely to have led to many species becoming isolated. The taxonomy of the stick insect genus Austrocarausius that is endemic to patchy rainforest habitats in Queensland, is poorly understood. We identify nine new species of this genus, bringing the total number of Austrocarausius species to eleven. We also investigate the evolution of the genus and perform molecular phylogenetic analysis of the representatives. We show that the genus began to diversify c. 25–70 Ma. [ABSTRACT FROM AUTHOR]

Species of Onnia are important tree pathogens and play a crucial role in forest ecosystems. The species diversity and distribution of Onnia have been studied, however, its evolutionary history is poorly understood. In this study, we reconstructed the phylogeny of Onnia using internal transcribed spacers (ITS) and large subunit (LSU) rDNA sequence data. Molecular clock analyses developed the divergence times of Onnia based on a dataset (ITS + LSU rDNA + rpb1 + rpb2 + tef1α). Reconstruct Ancestral State in Phylogenies (RASP) was used to reconstruct the historical biogeography for the genus Onnia with a Dispersal Extinction Cladogenesis (DEC) model. Here, we provide a robust phylogeny of Onnia, with a description of a new species, Onnia himalayana from Yunnan Province, China. Molecular clock analyses suggested that the common ancestor of Onnia and Porodaedalea emerged in the Paleogene period with full support and a mean stem age of 56.9 Mya (95% highest posterior density of 35.9–81.6 Mya), and most species occurred in the Neogene period. Biogeographic studies suggest that Asia, especially in the Hengduan-Himalayan region, is probably the ancestral area. Five dispersals and two vicariances indicate that species of Onnia were rapidly diversified. Speciation occurred in the Old World and New World due to geographic separation. This study is the first inference of the divergence times, biogeography, and speciation of the genus Onnia. [ABSTRACT FROM AUTHOR]

Orf virus (ORFV) is distributed worldwide and is the causative agent of contagious ecthyma that mainly occurs in sheep and goats. This disease was reported for the first time at the end of 18th century in Europe but very little is currently known about the temporal and geographic origins of this virus. In the present study, the use of new Italian whole genomes allowed for better inference on the evolutionary history of ORFV. In accordance with previous studies, two genome types (S and G) were described for infection of sheep and goats, respectively. These two well-differentiated groups of genomes originated for evolutive convergence in the late 1800s in two different areas of the world (Europe for S type and Asia for G type), but it was only in the early 1900s that the effective size of ORFV increased among hosts and the virus spread across the whole European continent. The Italian strains which were sequenced in the present study were isolated on the Mediterranean island of Sardinian and showed to be exclusive to this geographic area. One of them is likely representative of the early European forms of ORFV which infected sheep and became extinct about one century ago. Such an ancient Sardinian strain may have reached the island simple by chance, where it quickly adapted to the new habitat. [ABSTRACT FROM AUTHOR]

In this study comparative phylogenetic analyses of huchonid fishes (Brachymystax and Hucho genera) were carried out by application of various computational methods based on the supermatrix data retrieved from NCBI Gene Bank. For this purpose, the available mitochondrial (3575 bp) and nuclear (2037 bp) DNA data originated from all extant huchonid species were used. Additionally, molecular dating was carried out to estimate time background of huchonids divergence. Phylogenetic analyses were conducted using the Neighbor‐joining (NJ), Maximum likelihood (ML), Maximum parsimony (MP) and Bayesian approach (BA) methods. The ancestral position of Brachymystax/Hucho cluster within Salmoninae subfamily was resolved and dated to emerge c.a. 24.7–25.6 million years ago (Mya). The evolutionary age of the most recent ancestor of contemporary huchonids was estimated to 10.6–13.6 Mya, while the oldest lineage within huchonid fishes was the genus Brachymystax (5.5–6.1 Mya). All three extant Hucho species were dated to split about 2.5 Mya, suggesting their disjunctive distribution during speciation. The highest heterogeneity was observed within Hucho taimen and Hucho bleekeri species, which clustered into two distinct phylogeographic groups, implying their vicariant origin from different glaciation refugees. The lowest level of genetic differentiation was recorded in Hucho hucho species, which may reflect past low population size, bottlenecks, founder effect and/or low rate of molecular clock. The carried out comparative analyses evidenced the discordance between nuclear and mitochondrial DNA data, indicating probable introgression between H. bleekeri and Brachymystax lenok that was estimated to take place around 5.5 Mya. The monotypic Parahucho genus was resolved as evolutionary younger and separate from huchonid lineage, that emerged around 15.8–13.2 Mya. [ABSTRACT FROM AUTHOR]

Asymmetrical rates of cladogenesis and extinction abound in the tree of life, resulting in numerous minute clades that are dwarfed by larger sister groups. Such taxa are commonly regarded as phylogenetic relicts or "living fossils" when they exhibit an ancient first appearance in the fossil record and prolonged external morphological stasis, particularly in comparison to their more diversified sister groups. Due to their special status, various phylogenetic relicts tend to be well-studied and prioritized for conservation. A notable exception to this trend is found within Amblypygi ("whip spiders"), a visually striking order of functionally hexapodous arachnids that are notable for their antenniform first walking leg pair (the eponymous "whips"). Paleoamblypygi, the putative sister group to the remaining Amblypygi, is known from Late Carboniferous and Eocene deposits but is survived by a single living species, Paracharon caecusHansen (1921), that was last collected in 1899. Due to the absence of genomic sequence-grade tissue for this vital taxon, there is no global molecular phylogeny for Amblypygi to date, nor a fossil-calibrated estimation of divergences within the group. Here, we report a previously unknown species of Paleoamblypygi from a cave site in Colombia. Capitalizing upon this discovery, we generated the first molecular phylogeny of Amblypygi, integrating ultraconserved element sequencing with legacy Sanger datasets and including described extant genera. To quantify the impact of sampling Paleoamblypygi on divergence time estimation, we performed in silico experiments with pruning of Paracharon. We demonstrate that the omission of relicts has a significant impact on the accuracy of node dating approaches that outweighs the impact of excluding ingroup fossils, which bears upon the ancestral range reconstruction for the group. Our results underscore the imperative for biodiversity discovery efforts in elucidating the phylogenetic relationships of "dark taxa," and especially phylogenetic relicts in tropical and subtropical habitats. The lack of reciprocal monophyly for Charontidae and Charinidae leads us to subsume them into one family, Charontidae, new synonymy., (© The Author(s) 2024. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background and Aims: Understanding the biogeographical patterns and processes underlying the distribution of diversity within the Northern Hemisphere has fascinated botanists and biogeographers for over a century. However, as a well-known centre of species diversity in the Northern Hemisphere, whether East Asia acted as a source and/or a sink of plant diversity of the Northern Hemisphere remains unclear. Here, we used Thalictroideae, a subfamily widely distributed in the Northern Hemisphere with the majority of species in East Asia, to investigate the role of East Asia in shaping the biogeographical patterns of the Northern Hemisphere and to test whether East Asia acted as a museum or a cradle for herbaceous taxa., Methods: Based on six plastid and one nuclear DNA regions, we generated the most comprehensive phylogeny for Thalictroideae including 217 taxa (ca. 66% species) from all ten of the currently recognized genera. Within this phylogenetic framework, we then estimated divergence times, ancestral ranges, and diversification rates., Key Results: The monophyletic Thalictroideae contains three major clades. All genera with more than one species are strongly supported as monophyletic except for Isopyrum, which is nested in Enemion. The most recent common ancestor of Thalictroideae occurred in East Asia in the late Eocene (ca. 36 Ma). From the Miocene onwards, at least 46 dispersal events were inferred to be responsible for the current distribution of this subfamily. East Asian Thalictroideae lineages experienced a rapid accumulation at ca. 10 Ma., Conclusions: The biogeographical patterns of Thalictroideae support the "out of and in East Asia" hypothesis, i.e., East Asia is both a source and a sink of biodiversity of the Northern Hemisphere. The global cooling after the middle Miocene Climatic Optimum, combined with the exposed land bridges due to sea-level decline, might have jointly caused the bidirectional plant exchanges between East Asia and other Northern Hemisphere regions. East Asia serves as evolutionary museums and cradles for the diversity of Thalictroideae and likely for other herbaceous lineages., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

In the present study, we have characterized the complete chloroplast (Cp) genome of Meconopsis torquata Prain (family Papaveraceae), revealing the plastome size of 153,290 bp, and a GC content of 38.72 %. The cp genome features the typical circular quadripartite structure found in flowering plants, including a pair of inverted repeat regions (25,816 bp), isolated by a small single-copy region (17,740 bp) and a large single-copy (83,918 bp). Genome annotation revealed 132 genes: 87 protein-coding genes, 37 tRNAs and eight rRNAs. This comparative study demonstrated that the genome structure, gene number and GC ratio are consistent with several other cp genomes of Meconopsis and Papaver genera. A total of 120 SSRs were detected in the plastome, the majority (111) of which were mononucleotide repeats. Among the longer repeats, palindromic sequences were most common, followed by forward, reverse, and complement repeats. The whole genome alignment revealed the conserved nature of the inverted repeat region over single-copy zones. Nucleotide diversity unveiled hypervariable sites ( ycf1 , rps16 , accD , atpB and psbD ) in both the small and large single-copy regions, which could be useful for designing molecular markers for taxonomic identification. Phylogenetic analysis revealed a close alliance of M. torquata with other Meconopsis species, such as M. pinnatifolia and M. paniculata , with strong bootstrap support. Molecular dating suggests that M. torquata originated during the Tortonian age of the Miocene epoch of the Cenozoic era. These findings provide valuable insights for biological research, especially in understanding the genetic and evolutionary divergence within the Papaveraceae family., Competing Interests: The authors hereby declare that there is no any conflicting interest concerning financial or personal issues that might have influenced the work presented in this paper., (© 2024 The Authors.)

Dating phylogenetic trees to obtain branch lengths in time unit is essential for many downstream applications but has remained challenging. Dating requires inferring substitution rates that can change across the tree. While we can assume to have information about a small subset of nodes from the fossil record or sampling times (for fast-evolving organisms), inferring the ages of the other nodes essentially requires extrapolation and interpolation. Assuming a distribution of branch rates, we can formulate dating as a constrained maximum likelihood (ML) estimation problem. While ML dating methods exist, their accuracy degrades in the face of model misspecification where the assumed parametric statistical distribution of branch rates vastly differs from the true distribution. Notably, most existing methods assume rigid, often unimodal, branch rate distributions. A second challenge is that the likelihood function involves an integral over the continuous domain of the rates and often leads to difficult non-convex optimization problems. To tackle these two challenges, we propose a new method called Molecular Dating using Categorical-models (MD-Cat). MD-Cat uses a categorical model of rates inspired by non-parametric statistics and can approximate a large family of models by discretizing the rate distribution into k categories. Under this model, we can use the Expectation- Maximization (EM) algorithm to co-estimate rate categories and branch lengths in time units. Our model has fewer assumptions about the true distribution of branch rates than parametric models such as Gamma or LogNormal distribution. Our results on two simulated and real datasets of Angiosperms and HIV and a wide selection of rate distributions show that MD-Cat is often more accurate than the alternatives, especially on datasets with exponential or multimodal rate distributions., (© The Author(s) 2024. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Abstract Insular woodiness (IW), referring to the evolutionary transition from herbaceousness toward woodiness on islands, has arisen more than 30 times on the Canary Islands (Atlantic Ocean). One of the IW hypotheses suggests that drought has been a major driver of wood formation, but we do not know in which palaeoclimatic conditions the insular woody lineages originated. Therefore, we provided an updated review on the presence of IW on the Canaries, reviewed the palaeoclimate, and estimated the timing of origin of woodiness of 24 insular woody lineages that represent a large majority of the insular woody species diversity on the Canaries. Our single, broad‐scale dating analysis shows that woodiness in 60%–65% of the insular woody lineages studied originated within the last 3.2 Myr, during which Mediterranean seasonality (yearly summer droughts) became established on the Canaries. Consequently, our results are consistent with palaeoclimatic aridification as a potential driver of woodiness in a considerable proportion of the insular woody Canary Island lineages. However, the observed pattern between insular woodiness and palaeodrought during the last couple of million years could potentially have emerged as a result of the typically young age of the native insular flora, characterized by a high turnover.

We investigated the globally distributed red algal genus Pterocladiella , comprising 24 described species, many of which are economically important sources of agar and agarose. We used DNA-based species delimitation approaches, phylogenetic, and historical biogeographical analyses to uncover cryptic diversity and infer the drivers of biogeographic patterns. We delimited 43 species in Pterocladiella , of which 19 are undescribed. Our multigene time-calibrated phylogeny and ancestral area reconstruction indicated that Pterocladiella most likely originated during the Early Cretaceous in the Tethys Sea. Ancient Tethyan vicariance and long-distance dispersal have shaped current distribution patterns. The ancestor of Eastern Pacific species likely arose before the formation of the formidable Eastern Pacific Barrier—a first confirmation using molecular data in red algae. Divergences of Northeast and Southeast Pacific species have been driven by the Central American Seaway barrier, which, paradoxically, served as a dispersal pathway for Atlantic species. Both long- and short-distance dispersal scenarios are supported by genetic relationships within cosmopolitan species based on haplotype analysis. Asymmetrical distributions and the predominance of peripatry and sympatry between sister species suggest the importance of budding speciation in Pterocladiella. Our study highlights the underestimation of global diversity in these crucial components of coastal ecosystems and provides evidence for the complex evolution of current species distributions. [ABSTRACT FROM AUTHOR]

Mites of the genus Analges (Acariformes: Analgidae) inhabit the down feathers of passeriform birds. The evolutionary history of Analges and the co-phylogentic relationships between these mites and their hosts are unknown. Our phylogenetic analysis supported the monophyly of the genus, but it did not support previous taxonomic hypotheses subdividing the genus into the subgenera Analges and Analgopsis or arranging some species into the A. chelopus and A. passerinus species groups. Molecular data reveal seven new species inhabiting Eurasian passerines and support the existence of several multi-host species. According to molecular dating, the origin of the Analges (c. 41 Mya) coincided with the Eocene diversification of Passerida into Sylvioidea and Muscicapoidea–Passeroidea. The initial diversification of Analges took place on the Muscicapoidea clade, while remaining passerine superfamilies appear to have been colonized because of host-switching. Co-speciation appears to be relatively common among Analges species and their hosts, but the most striking pattern in the co-phylogenetic scenario involves numerous complete host-switches, spreads and several failures to speciate. The mechanism of long-term gene-flow among different populations of multi-host Analges species is enigmatic and difficult to resolve. Probably, in some cases mites could be transferred between birds via feathers used as nest material. [ABSTRACT FROM AUTHOR]

Tropical alpine floras are renowned for high endemism, spectacular giant rosette plants testifying to convergent adaptation to harsh climates with nightly frosts, and recruitment dominated by long-distance dispersal from remote areas. In contrast to the larger, more recent (late Miocene onward) and contiguous expanses of tropical alpine habitat in South America, the tropical alpine flora in Africa is extremely fragmented across small patches on distant mountains of variable age (Oligocene onward). How this has affected the colonization and diversification history of the highly endemic but species-poor afroalpine flora is not well known. Here we infer phylogenetic relationships of ~20% of its species using novel genome skimming data and published matrices and infer a timeframe for species origins in the afroalpine region using fossil-calibrated molecular clocks. Although some of the mountains are old, and although stem node ages may substantially predate colonization, most lineages appear to have colonized the afroalpine during the last 5 or 10 My. The accumulation of spe-cies increased exponentially toward the present. Taken together with recent reports of extremely low intrapopulation genetic diversity and recent intermountain population divergence, this points to a young, unsaturated, and dynamic island scenario. Habitat disturbance caused by the Pleistocene climate oscillations likely induced cycles of colonization, speciation, extinction, and recolonization. This study contributes to our understanding of differences in the histories of recruitment on different tropical sky islands and on oceanic islands, providing insight into the general processes shaping their remarkable floras. [ABSTRACT FROM AUTHOR]

Four endemic coronaviruses infect humans and cause mild symptoms. Because previous analyses were based on a limited number of sequences and did not control for effects that affect molecular dating, we re-assessed the timing of endemic coronavirus emergence. After controlling for recombination, selective pressure, and molecular clock model, we obtained similar tMRCA (time to the most recent common ancestor) estimates for the four coronaviruses, ranging from 72 (HCoV-229E) to 54 (HCoV-NL63) years ago. The split times of HCoV-229E and HCoV-OC43 from camel alphacoronavirus and bovine coronavirus were dated ~268 and ~99 years ago. The split times of HCoV-HKU1 and HCoV-NL63 could not be calculated, as their zoonoticic sources are unknown. To compare the timing of coronavirus emergence to that of another respiratory virus, we recorded the occurrence of influenza pandemics since 1500. Although there is no clear relationship between pandemic occurrence and human population size, the frequency of influenza pandemics seems to intensify starting around 1700, which corresponds with the initial phase of exponential increase of human population and to the emergence of HCoV-229E. The frequency of flu pandemics in the 19th century also suggests that the concurrence of HCoV-OC43 emergence and the Russian flu pandemic may be due to chance. [ABSTRACT FROM AUTHOR]

Saccharomycotina yeasts belong to diverse clades within the kingdom of fungi and are important to human everyday life. This work investigates the evolutionary relationships among these yeasts from a mitochondrial (mt) genomic perspective. A comparative study of 155 yeast mt genomes representing all major phylogenetic lineages of Saccharomycotina was performed, including genome size and content variability, intron and intergenic regions' diversity, genetic code alterations, and syntenic variation. Findings from this study suggest that mt genome size diversity is the result of a ceaseless random process, mainly based on genetic recombination and intron mobility. Gene order analysis revealed conserved syntenic units and many occurring rearrangements, which can be correlated with major evolutionary events as shown by the phylogenetic analysis of the concatenated mt protein matrix. For the first time, molecular dating indicated a slower mt genome divergence rate in the early stages of yeast evolution, in contrast with a faster rate in the late evolutionary stages, compared to their nuclear time divergence. Genetic code reassignments of mt genomes are a perpetual process happening in many different parallel evolutionary steps throughout the evolution of Saccharomycotina. Overall, this work shows that phylogenetic studies based on the mt genome of yeasts highlight major evolutionary events. [ABSTRACT FROM AUTHOR]

The Neotropical tinamous are of particular interest in our efforts to understand the evolution of modern birds. They inhabit both forested and open environments and, although volant, have limited flight capabilities. Numerous studies have recognized the monophyly of tinamous and their relationships either as sister to the flightless ratites (ostriches, emus and their relatives) or within the ratites themselves. Despite the numerous bird phylogenies published recently, modern investigations of relationships within the tinamous themselves have been limited. Here, we present the first detailed phylogenetic analysis and divergence-date estimation including a significant number of tinamou species, both extant and fossil. The monophyly of most currently recognized polytypic genera is recovered with high support, with the exception of the paraphyletic Nothura and Nothoprocta. The traditional subdivision between those tinamous inhabiting open areas (Nothurinae) and forest environments (Tinaminae) is also confirmed. A temporal calibration of the resultant phylogeny estimates that the basal divergence of crown Tinamidae took place between 31 and 40 Mya. [ABSTRACT FROM AUTHOR]

Grasses are widespread on every continent and are found in all terrestrial biomes. The dominance and spread of grasses and grassland ecosystems have led to significant changes in Earth′s climate, geochemistry, and biodiversity. The abundance of DNA sequence data, particularly chloroplast sequences, and advances in placing grass fossils within the family allows for a reappraisal of the family′s origins, timing, and geographic spread and the factors that have promoted diversification. We reconstructed a time‐calibrated grass phylogeny and inferred ancestral areas using chloroplast DNA sequences from nearly 90% of extant grass genera. With a few notable exceptions, the phylogeny is well resolved to the subtribal level. The family began to diversify in the Early–Late Cretaceous (crown age of 98.54 Ma) on West Gondwana before the complete split between Africa and South America. Vicariance from the splitting of Gondwana may be responsible for the initial divergence in the family. However, Africa clearly served as the center of origin for much of the early diversification of the family. With this phylogenetic, temporal, and spatial framework, we review the evolution and biogeography of the family with the aim to facilitate the testing of biogeographical hypotheses about its origins, evolutionary tempo, and diversification. The current classification of the family is discussed with an extensive review of the extant diversity and distribution of species, molecular and morphological evidence supporting the current classification scheme, and the evidence informing our understanding of the biogeographical history of the family. [ABSTRACT FROM AUTHOR]

The Dasylirion genus is highly represented in the arid and semi-arid regions of Mexico and USA, playing important ecological and economical roles. Inferring the evolutionary patterns of this group will eventually facilitate understanding biological phenomena and outlining conservation and usage strategies. We performed a molecular phylogenetic analysis based on two chloroplast DNA regions: maturase-K gene (matK) and the large subunit of ribulose-1,5-bisphosphate carboxylase gene (rbcL). We constructed a phylogenetic tree by maximum likelihood with GTR as the sequence substitution model and a relaxed clock, inferred diversification patterns by lineage through time and explored the diversification rates of Dasylirion by the Yule model. The study included 11 species of the genus, which represent 50% of all its known species. We used two calibration points to date the tree, one based on fossil records of Acorus gramineus , and the other on the estimated stem age of the Yucca genus. The combined sequences of the two partial genes comprised 1455 bp and 18 polymorphic sites. We estimated an average substitution rate of 0.0005 nucleotide per million years for the concatenated DNA sequences. The molecular dating analysis estimated that the Dasylirion genus appeared more than 5.46 million years ago, with a rate of diversification of 0.0466 net speciation events per million years. The estimated age represents a lower bound, since not all Dasylirion species are included. These findings are consistent with other origin and diversification hypotheses for arid-land Asparagaceae in the Mexican highlands as a result of geomorphological events in North America. [ABSTRACT FROM AUTHOR]

Background and Aims Theaceae, with three tribes, nine genera and more than 200 species, are of great economic and ecological importance. Recent phylogenetic analyses based on plastomic data resolved the relationships among the three tribes and the intergeneric relationships within two of those tribes. However, generic-level relationships within the largest tribe, Theeae, were not fully resolved. The role of putative whole-genome duplication (WGD) events in the family and possible hybridization events among genera within Theeae also remain to be tested further. Methods Transcriptomes or low-depth whole-genome sequencing of 57 species of Theaceae, as well as additional plastome sequence data, were generated. Using a dataset of low-copy nuclear genes, we reconstructed phylogenetic relationships using concatenated, species tree and phylogenetic network approaches. We further conducted molecular dating analyses and inferred possible WGD events by examining the distribution of the number of synonymous substitutions per synonymous site (Ks) for paralogues in each species. For plastid protein-coding sequences , phylogenies were reconstructed for comparison with the results obtained from analysis of the nuclear dataset. Results Based on the 610 low-copy nuclear genes (858 606 bp in length) investigated, Stewartieae was resolved as sister to the other two tribes. Within Theeae, the Apterosperma – Laplacea clade grouped with Pyrenaria , leaving Camellia and Polyspora as sister. The estimated ages within Theaceae were largely consistent with previous studies based mainly on plastome data. Two reticulation events within Camellia and one between the common ancestor of Gordonia and Schima were found. All members of the tea family shared two WGD events, an older At-γ and a recent Ad-β; both events were also shared with the outgroups (Diapensiaceae, Pentaphylacaceae, Styracaceae and Symplocaceae). Conclusions Our analyses using low-copy nuclear genes improved understanding of phylogenetic relationships at the tribal and generic levels previously proposed based on plastome data, but the phylogenetic position of the Apterosperma–Laplacea clade needs more attention. There is no evidence for extensive intergeneric hybridization within Theeae or for a Theaceae-specific WGD event. Land bridges (e.g. the Bering land bridge) during the Late Oligocene may have permitted the intercontinental plant movements that facilitated the putative ancient introgression between the common ancestor of Gordonia and Schima. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biogeographic hypothesis testing and ancestral area reconstruction supports an origin of Bombycidae in Southern Gondwana during the Paleocene (c. 64 Mya). • Bombycidae differentiated into two subfamilies by vicariance between South America (Epiinae) and Australia (Bombycinae) during the Eocene (c. 56 Mya). • Although most species of Bombycinae are distributed in South-East Asia, they did not originate in the Oriental Region. Rather, the ancestor dispersed out of Australia to South-East Asia during the Eocene (c. 53 Mya) or possibly later. • A second dispersal event occurred from Asia to Africa during the Miocene (c. 16 Mya), most likely facilitated by the Gomphotherium land bridge. • Our study provides an explanation for the group's disjunct distribution in the Southern Hemsiphere and Asia, which, interestingly, does not involve dispersal across Beringia. Silkmoths (Bombycidae) have a disjunct distribution predominantly in the Southern Hemisphere and Asia. Here we reconstruct the phylogenetic history of the family to test competing hypotheses on their origin and assess how vicariance and long-distance dispersal shaped their current distribution. We sequenced up to 5,074 base pairs from six loci (COI, EF1-α, wgl, CAD, GAPDH, and RpS5) to infer the historical biogeography of Bombycidae. The multilocus dataset covering 20 genera (80 %) of the family, including 17 genera (94 %) of Bombycinae and 3 genera (43 %) of Epiinae, was used to estimate phylogenetic patterns, divergence times and biogeographic reconstruction. Dating estimates extrapolated from secondary calibration sources indicate the Bombycidae stem-group originated approximately 64 Mya. The subfamilies Epiinae (South America) and Bombycinae (Australia, Asia, East Palaearctic, and Africa) were reciprocally monophyletic, diverging at c. 56 Mya (95 % credibility interval: 66–46 Mya). The 'basal' lineage of Bombycinae — Gastridiota + Elachyophtalma — split from the rest of Bombycinae c. 53 Mya (95 % credibility interval: 63–43 Mya). Gastridiota is a monobasic genus with a relictual distribution in subtropical forests of eastern Australia. The Oriental and African genera comprised a monophyletic group: the Oriental region was inferred to have been colonized from a long-distance dispersal event from Australia to South-East Asia c. 53 Mya or possibly later (c. 36–26 Mya); Africa was subsequently colonized by dispersal from Asia c. 16 Mya (95 % credibility interval: 21–12 Mya). Based on the strongly supported phylogenetic relationships and estimates of divergence times, we conclude that Bombycidae had its origin in the fragment of Southern Gondwana consisting of Australia, Antarctica and South America during the Paleocene. The disjunction between South America (Epiinae) and Australia (Bombycinae) is best explained by vicariance in the Eocene, whereas the disjunct distribution in Asia and Africa is best explained by more recent dispersal events. [ABSTRACT FROM AUTHOR]

We investigated the globally distributed red algal genus Pterocladiella, comprising 24 described species, many of which are economically important sources of agar and agarose. We used DNA-based species delimitation approaches, phylogenetic, and historical biogeographical analyses to uncover cryptic diversity and infer the drivers of biogeographic patterns. We delimited 43 species in Pterocladiella, of which 19 are undescribed. Our multigene time-calibrated phylogeny and ancestral area reconstruction indicated that Pterocladiella most likely originated during the Early Cretaceous in the Tethys Sea. Ancient Tethyan vicariance and long-distance dispersal have shaped current distribution patterns. The ancestor of Eastern Pacific species likely arose before the formation of the formidable Eastern Pacific Barrier—a first confirmation using molecular data in red algae. Divergences of Northeast and Southeast Pacific species have been driven by the Central American Seaway barrier, which, paradoxically, served as a dispersal pathway for Atlantic species. Both long- and short-distance dispersal scenarios are supported by genetic relationships within cosmopolitan species based on haplotype analysis. Asymmetrical distributions and the predominance of peripatry and sympatry between sister species suggest the importance of budding speciation in Pterocladiella. Our study highlights the underestimation of global diversity in these crucial components of coastal ecosystems and provides evidence for the complex evolution of current species distributions.

[Display omitted] • A fossil-calibrated densely-sampled molecular phylogeny strongly supported the monophyly of Harpalyce and its placement in the tribe Brongniartieae. • Stochastic character mapping revealed peltate glandular trichomes and a bilabiate calyx as synapomorphies of Harpalyce. • Harpalyce originated in South America during the Miocene at around 20 Ma. • Harpalyce underwent synchronous diversification in South America and Mexico/Mesoamerica since 10 Ma. • Migration of Harpalyce from South to North America was accompanied by a biome shift from savanna to seasonally dry forest ecology. Our knowledge of the systematics of the papilionoid legume tribe Brongniartieae has greatly benefitted from recent advances in molecular phylogenetics. The tribe was initially described to include species marked by a strongly bilabiate calyx and an embryo with a straight radicle, but recent research has placed taxa from the distantly related core Sophoreae and Millettieae within it. Despite these advances, the most species-rich genera within the Brongniartieae are still not well studied, and their morphological and biogeographical evolution remains poorly understood. Comprising 35 species, Harpalyce is one of these poorly studied genera. In this study, we present a comprehensive, multi-locus molecular phylogeny of the Brongniartieae, with an increased sampling of Harpalyce , to investigate morphological and biogeographical evolution within the group. Our results confirm the monophyly of Harpalyce and indicate that peltate glandular trichomes and a strongly bilabiate calyx with a carinal lip and three fused lobes are synapomorphies for the genus, which is internally divided into three distinct ecologically and geographically divergent lineages, corresponding to the previously recognized sections. Our biogeographical reconstructions demonstrate that Brongniartieae originated in South America during the Eocene, with subsequent pulses of diversification in South America, Mesoamerica, and Australia. Harpalyce also originated in South America during the Miocene at around 20 Ma, with almost synchronous later diversification in South America and Mexico/Mesoamerica beginning 10 Ma, but mostly during the Pliocene. Migration of Harpalyce from South to North America was accompanied by a biome and ecological shift from savanna to seasonally dry forest. [ABSTRACT FROM AUTHOR]

[Display omitted] • Most comprehensive phylogenomic analysis of Ricinulei using UCEs. • First molecular analysis to recover support for an Andean clade of Cryptocellus. • Provides insight into the complex biogeography of low-vagility Caribbean arthropods. • Highlights the need for integrative taxonomy to revise the systematics of the group. Ricinulei or hooded tick-spiders are a cryptic and ancient group of arachnids. The order consists of around 100 highly endemic extant species restricted to the Afrotropics and the Neotropics along with 22 fossil species. Their antiquity and low vagility make them an excellent group with which to interrogate biogeographic questions. To date, only four molecular analyses have been conducted on the group and they failed to resolve the relationships of the main lineages and even recovering the non-monophyly of the three genera. These studies were limited to a few Sanger loci or phylogenomic analyses with at most seven ingroup samples. To increase phylogenetic resolution in this little-understood and poorly studied group, we present the most comprehensive phylogenomic study of Ricinulei to date leveraging the Arachnida ultra-conserved element probe set. With a data set of 473 loci across 96 ingroup samples, analyses resolved a monophyletic Neotropical clade consisting of four main lineages. Two of them correspond to the current genera Cryptocellus and Pseudocellus while topology testing revealed one lineage to likely be a phylogenetic reconstruction artefact. The fourth lineage, restricted to Northwestern, Andean South America, is consistent with the Cryptocellus magnus group, likely corresponding to the historical genus Heteroricinoides. Since we did not sample the type species for this old genus, we do not formally re-erect Heteroricinoides but our data suggest the need for a thorough morphological re-examination of Neotropical Ricinulei. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA (mtDNA), being maternally inherited in plants of the family Pinaceae, is an important source of phylogeographic information. However, its use is hindered by a low mutation rate and frequent structure rearrangements. In the present study, we tested the method of genomic libraries enrichment with mtDNA via the sequence capture method yielding mtDNA data which were further used to reconstruct the phylogenetic tree of the genus Abies. The baits for hybrid capture were obtained by long-range PCR using primers designed on the basis of the assembly of Abies sibirica Ledeb. mitochondrial genome. Mitochondrial genomes of Picea sitchensis (Bong.) Carr., Larix sibirica Ledeb., and Keteleeria davidiana (Bertrand) Beissn. were used as an outgroup. The resulting phylogenetic tree consists of two sister branches, including the Eurasian and American species, respectively, with some exceptions. The subclade of A. sachalinensis (F. Schmidt) Mast. and A. veitchii Lindl. (Japan and Sakhalin islands) occupies a basal position in the branch of American firs, probably due to the complex history of fir migrations from North America to Eurasia. The tree has high support for majority of clades. For species represented by more than one sample an intraspecific variability was found which is suitable to design mtDNA markers for phylogeographic and population studies. [ABSTRACT FROM AUTHOR]

Aim: Oceanic islands have played an important role in our understanding of the diversification of organisms, and phylogenetic estimates have been used in this context to investigate the origin of island diversity and its relationship to the continent. Using a typical orchid genus rich in island endemics and with widespread continental relatives, we aim to compare alternative hypotheses of diversification with a focus on island endemism. Location: Tropical Africa and the Gulf of Guinea Islands of São Tomé & Príncipe, Central Africa. Taxon Tridactyle genus (Orchidaceae). Methods: We used genome skimming to sequence the whole chloroplast genome and nuclear ribosomal genes from 157 individuals of 34 Tridactyle species and 15 individuals of 12 other orchid genera (outgroups) to infer a time‐calibrated phylogenetic tree of the genus Tridactyle. We also used multiple statistical methods to infer the geographical ranges of the ancestral nodes from the estimated phylogeny. Alternative hypotheses for the origins of endemism on the islands of São Tomé and Príncipe were investigated based on the biogeographical reconstruction of the genus. Results: The estimated phylogeny of Tridactyle and reconstruction of geographical ranges for the ancestral nodes suggested a general history of allopatric speciation for the genus, in particular via colonization of the islands of the Gulf of Guinea that induced a long period of geographical isolation. The most parsimonious hypothesis to explain island endemism in Tridactyle involved six independent colonizations of the islands from the continent. Main conclusions: In contrast to other cases of oceanic island endemism that involved adaptive radiation on an island or within an archipelago, endemism in Tridactyle is better explained by multiple colonization events from the continent to São Tomé and Príncipe, with subsequent divergences due to geographical isolation but only one potential instance of further diversification on the islands. [ABSTRACT FROM AUTHOR]

Freshwater mussels are known to have two types of mitochondrial DNA (mtDNA) transmitted separately through oocytes and sperms, namely, maternal (F‐type) and paternal (M‐type) mtDNA. The additional suite of mitochondrial genes provides a great opportunity to resolve phylogenetically problematic relationships. East Asian freshwater mussels of the genus Cuneopsis were considered a compact group of taxa having wedge‐shaped shells. However, preliminary results from previous studies challenged the monophyly of Cuneopsis, and the exact phylogenetic relationships among Cuneopsis and its allied genera are yet to be determined with comprehensive species sampling. Here, we evaluated species boundaries in Cuneopsis based on COI barcoding and obtained 11 new F‐ and M‐type mitogenomes via genome skimming to elucidate the evolutionary history of Cuneopsis. COI barcode data supported the validity of all sampled six Cuneopsis species (missing C. kiangsiensis). Our mitochondrial phylogenomic analyses confirmed that the currently recognized genus Cuneopsis sensu lato was polyphyletic, recovering three well‐supported clades. Molecular dating analysis suggested Cuneopsis s.l. diversified at ~58.06 million years ago in the Paleogene. Hereby, we propose two new genera, that is, Arcuneopsis gen. nov. and Pseudocuneopsis gen. nov. Additionally, we report a new species, Pseudocuneopsis sichuanensis sp. nov., from Chengdu, Sichuan, China, and a newly recorded species from China, Cuneopsis demangei. [ABSTRACT FROM AUTHOR]

The Caribbean Archipelago is a biodiversity hotspot that plays a key role in developing our understanding of how dispersal ability affects species formation. In island systems, species with intermediate dispersal abilities tend to exhibit greater diversity, as may be the case for many of the salticid lineages of the insular Caribbean. Here, we use molecular phylogenetic analyses to infer patterns of relationships and biogeographic history of the Caribbean endemic Antillattus clade (Antillattus, Truncattus, and Petemethis). We test if the timing of origin of the Antillatus clade in the Greater Antilles is congruent with GAARlandia and infer patterns of diversification within the Antillattus clade among Cuba, Hispaniola, and Puerto Rico. Specifically, we evaluate the relative roles of dispersal over land connections, and overwater dispersal events in diversification within the Greater Antilles. Time tree analysis and model-based inference of ancestral ranges estimated the ancestor of the Antillattus clade to be c. 25 Mya, and the best model suggests dispersal via GAARlandia from northern South America to Hispaniola. Hispaniola seems to be the nucleus from which ancestral populations dispersed into Cuba and Puerto Rico via land connections prior to the opening of the Mona Passage and the Windward Passage. Divergences between taxa of the Antillattus clade from Cuban, Hispaniolan, and Puerto Rican populations appear to have originated by vicariance, founder-events and within-island speciation, while multiple dispersal events (founder-events) between Cuba and Hispaniola during the Middle Miocene and the Late Miocene best explain diversity patterns in the genera Antillattus and Truncattus. [ABSTRACT FROM AUTHOR]

The Fritillaria is an extremely complicated genus in taxonomy and phylogeny, which contains numerous medicinal species in China. Both traditional characteristic-based taxonomy and universal DNA barcodes (ITS, trnH - psbA , and rbcL) are difficult to effectively identify the species. Here, we generated a large dataset of chloroplast genomes from multiple accessions per species of Fritillaria to evaluate their effectiveness in species discrimination. Moreover, phylogeny of species in China was explored based on the complete chloroplast genomes, and then divergence times of each node were estimated. The results showed that all 21 species in Fritillaria here (including two suspicious species) could be correctly discriminated using cpDNA genomes except F. cirrhosa , which suggested that DNA super-barcode could greatly enhance species discriminatory resolution for complicated genera. Furthermore, four regions (ycf1 , matK - trnG-GCC , rpoC1 , and matK) gained remarkably higher resolution than that of other plastid regions, but only matK might be suitable to identify Fritillaria species in consideration of its lengths. Phylogenomic analysis showed that the subgenus Fritillaria in China was divided into four major clades with obvious geographic structure. Among them, Clade I, mainly distributed in southwest China, was a young and complicated group. Moreover, according to the analysis, taxonomic treatments of the two suspicious species, namely " F. omeiensis " and " F. hupehensis " in Flora of China (2000) are questionable and might need further revision. Molecular dating revealed that both origin and divergence of subgenus Fritillaria , as well as its four major clades, were significantly associated with geological and climatic fluctuations during the Middle to Late Miocene. This study would enrich case studies of DNA super-barcode and provide new insights on speciation, lineage diversification, and biogeography of the Fritillaria in China. [ABSTRACT FROM AUTHOR]

Dipterocarpoideae, the largest subfamily in the Meranti family (Dipterocarpaceae) are an ecologically dominant group of trees throughout much of wet tropical Asia. Increasing anthropogenic pressures on this economically important tree family make it essential to resolve their complex evolutionary relationships and understand the distribution of genetic diversity throughout the family and distribution range. Dipterocarpaceae have been the focal group in a wide range of studies, owing to their economic value, importance in historical biogeography and key role in the evolution of the Asian tropical forest biome. Despite this, persistent taxonomic and evolutionary questions remain, ranging from questions on the geographic origin, sequence of dispersal and the identification of diagnostic characters to circumscribe proper evolutionary groups. Here we present a comprehensive phylogenomic hypothesis for Dipterocarpoideae, based on the analyses of plastome and nuclear cistron (NRC) data, and provide an in‐depth review on the validity of morphological characters underlying the new tribal classification proposed here for the subfamily. Phylogenomic relationships were inferred using maximum likelihood and Bayesian approaches. Estimates of origin and onset of diversification in major clades and lineages were reconstructed using plastome, nuclear and combined datasets. Results of the separate and combined genomic datasets partly corroborate elements of previous classification systems (with improved support at all levels for major clades) but provide strong support for revising the tribal classification of the subfamily into four main clades: Dipterocarpeae (Dipterocarpus), Dryobalanopseae (Dryobalanops), Shoreeae (Hopea, Neobalanocarpus, Parashorea, and all parts of a polyphyletic Shorea) and Vaterieae (including all other presently accepted Dipterocarpoideae genera). Multi‐fossil‐dated divergence time estimation suggests Vaterieae first originated in the Late Cretaceous, followed by Dipterocarpeae, with subsequent rise of the Dryobalanopseae and Shoreeae in the Eocene. Diversification of all tribes commenced before the Early Miocene. Our results provide strong support for the position of Neobalanocarpus heimii, Parashorea and (sub‐)sections of the genera Anisoptera, Hopea, Shorea and Vatica. Hypotheses on the origin of Neobalanocarpus heimii by intergeneric hybridisation between Anthoshorea (maternally inherited) and Hopea (paternally inherited) species were corroborated. Finally, our study provides support for future revisionary changes: (1) the elevation to generic rank of sections in Shorea; and (2) revising the infrageneric classification of Hopea as all (sub‐)sections were recovered as not monophyletic. [ABSTRACT FROM AUTHOR]

The Himalaya–Hengduan Mountain (HHM) region consists of two global biodiversity hotspots characterized by a high degree of plant endemism. However, little is known about how these endemic species are formed and maintained in relation to the regional geomorphology of the past or current time. Thus, this study investigated the genetic structure of the herbaceous genus Acanthocalyx (Caprifoliaceae) endemic to the HHM to demonstrate if major geographic or ecological barriers in the HHM region have influenced its phylogeographic patterns. Our analyses revealed distinct genetic structures within A. alba and A. nepalensis and indicated that A. delavayi may have recently evolved from isolated peripheral populations of A. nepalensis. In particular, we not only confirmed a well-known genetic structure of alpine plants between the Himalayas and the Hengduan Mountains but also discovered a notable floristic boundary (bounded by 30° to 31°N latitude) within the Hengduan Mountains from A. alba. This study provides new insights into the dispersal and intraspecific genetic variation of Acanthocalyx and highlights the importance of geomorphological features for the diversification of HHM alpine flora. [ABSTRACT FROM AUTHOR]

Aucuba (Garryaceae), which includes approximately ten evergreen woody species, is a genus endemic to East Asia. Their striking morphological features give Aucuba species remarkable ornamental value. Owing to high levels of morphological divergence and plasticity, species definitions of Aucuba remain perplexing and problematic. Here, we sequenced and characterized the complete plastid genomes (plastomes) of three Aucuba species: Aucuba chlorascens , Aucuba eriobotryifolia , and Aucuba japonica. Incorporating Aucuba plastomes available in GenBank, a total of seven Aucuba plastomes, representing six out of ten species of Aucuba , were used for comparative plastome analysis, phylogenetic analysis and divergence time estimation in this study. Comparative analyses revealed that plastomes of Aucuba are highly conserved in size, structure, gene content, and organization, and exhibit high levels of sequence similarity. Phylogenetic reconstruction based on 68 plastid protein-coding genes strongly supported the monophyly of Garryales, Garryaceae and Aucuba. Aucuba eriobotryifolia was sister to the other Aucuba species examined, consistent with its unique fused anther locule. The divergence time of Aucuba was estimated to be approximately late Miocene. Extant Aucuba species derived from recent divergence events associated with the establishment of monsoonal climates in East Asia and climatic fluctuations. [ABSTRACT FROM AUTHOR]

The early-diverging eudicot family Berberidaceae is composed of a morphologically diverse assemblage of disjunctly distributed genera long praised for their great horticultural and medicinal values. However, despite century-long studies, generic delimitation of Berberidaceae remains controversial and its tribal classification has never been formally proposed under a rigorous phylogenetic context. Currently, the number of accepted genera in Berberidaceae ranges consecutively from 13 to 19, depending on whether to define Berberis , Jeffersonia , and Podophyllum broadly, or to segregate these three genera further and recognize Alloberberis , Mahonia , and Moranothamnus , Plagiorhegma , and Dysosma , Diphylleia , and Sinopodophyllum , respectively. To resolve Berberidaceae's taxonomic disputes, we newly assembled 23 plastomes and, together with 85 plastomes from the GenBank, completed the generic sampling of the family. With 4 problematic and 14 redundant plastome sequences excluded, robust phylogenomic relationships were reconstructed based on 93 plastomes representing all 19 genera of Berberidaceae and three outgroups. Maximum likelihood phylogenomic relationships corroborated with divergence time estimation support the recognition of three subfamilies Berberidoideae, Nandinoideae, and Podophylloideae, with tribes Berberideae and Ranzanieae, Leonticeae and Nandineae, and Podophylleae, Achlydeae, Bongardieae tr. nov. , Epimedieae, and Jeffersonieae tr. nov. in the former three subfamilies, respectively. By applying specifically stated criteria, our phylogenomic data also support the classification of 19 genera, recognizing Alloberberis , Mahonia , and Moranothamnus , Plagiorhegma , and Diphylleia , Dysosma , and Sinopodophyllum that are morphologically and evolutionarily distinct from Berberis , Jeffersonia , and Podophyllum , respectively. Comparison of plastome structures across Berberidaceae confirms inverted repeat expansion in the tribe Berberideae and reveals substantial length variation in accD gene caused by repeated sequences in Berberidoideae. Comparison of plastome tree with previous studies and nuclear ribosomal DNA (nrDNA) phylogeny also reveals considerable conflicts at different phylogenetic levels, suggesting that incomplete lineage sorting and/or hybridization had occurred throughout the evolutionary history of Berberidaceae and that Alloberberis and Moranothamnus could have resulted from reciprocal hybridization between Berberis and Mahonia in ancient times prior to the radiations of the latter two genera. [ABSTRACT FROM AUTHOR]

Despite the importance of natural selection in species' evolutionary history, phylogenetic methods that take into account population-level processes typically ignore selection. The assumption of neutrality is often based on the idea that selection occurs at a minority of loci in the genome and is unlikely to compromise phylogenetic inferences significantly. However, genome-wide processes like GC-bias and some variation segregating at the coding regions are known to evolve in the nearly neutral range. As we are now using genome-wide data to estimate species trees, it is natural to ask whether weak but pervasive selection is likely to blur species tree inferences. We developed a polymorphism-aware phylogenetic model tailored for measuring signatures of nucleotide usage biases to test the impact of selection in the species tree. Our analyses indicate that although the inferred relationships among species are not significantly compromised, the genetic distances are systematically underestimated in a node-height-dependent manner: that is, the deeper nodes tend to be more underestimated than the shallow ones. Such biases have implications for molecular dating. We dated the evolutionary history of 30 worldwide fruit fly populations, and we found signatures of GC-bias considerably affecting the estimated divergence times (up to 23%) in the neutral model. Our findings call for the need to account for selection when quantifying divergence or dating species evolution. [ABSTRACT FROM AUTHOR]

Aim: Palaeoceanographic changes can act as drivers of diversification and speciation, even in highly mobile marine organisms. Shearwaters are a group of globally distributed and highly mobile pelagic seabirds. Despite a recent well‐resolved phylogeny, shearwaters have controversial species limits, and show periods of both slow and rapid diversification. Here, we explore the role of palaeoceanographic changes on shearwaters' diversification and speciation. We investigate shearwater biogeography and the evolution of a key phenotypic trait, body size, and we assess the validity of their current taxonomy. Location: Worldwide. Taxa: Shearwaters (Order Procellariiformes, Family Procellariidae, Genera Ardenna, Calonectris and Puffinus). Methods: We generated genomic (ddRAD) data to infer a time‐calibrated species tree for the shearwaters. We estimated ancestral ranges and evaluated the roles of founder events, vicariance and surface ocean currents in driving diversification. We performed phylogenetic generalised least squares to identify potential predictors of variability in body size along the phylogeny. To assess the validity of the current taxonomy, we analysed genomic patterns of recent shared ancestry and differentiation among shearwater taxa. Results: We identified a period of high dispersal and rapid speciation during the Late Pliocene–early Pleistocene. Species dispersal appears to be favoured by surface ocean currents, and founder events are supported as the main mode of speciation in these highly mobile pelagic seabirds. Body mass shows significant associations with life strategies and local conditions. The current taxonomy shows some incongruences with the patterns of genomic divergence. Main Conclusions: A reduction of neritic areas during the Pliocene seems to have driven global extinctions of shearwater species, followed by a subsequent burst of speciation and dispersal probably promoted by Plio‐Pleistocene climatic shifts. Our findings extend our understanding on the drivers of speciation and dispersal of highly mobile pelagic seabirds and shed new light on the important role of palaeoceanographic events. [ABSTRACT FROM AUTHOR]

The extremely difficult and challenging process is identifying pheretimoid species, genus Metaphire and Amynthas involving increased homoplasy in various morphological characteristics. The molecular identification, phylogenetic relationships, and evolutionary divergence time of earthworms belonging to the pheretimoid complex were investigated in this study using partial mitochondrial COI (cytochrome C oxidase subunit I) gene sequences ranging from 550-680 bp. Results revealed that 86 pheretimoid earthworms were morphologically different from a total of 342 mature worms. Moreover, 11 pheretimoid species were molecularly identified, including Metaphire posthuma (02), M. anomala (01), M. houlleti (02), M. californica (01), M. birmanica (02), Amynthas minimus (01), A. morrisi (01), and M. bununa (01). A phylogenetic tree was constructed with bootstrap values of 95%, which supported a monophyletic lineage of two well-supported clades formed by 12 partial COI sequences and 48 GenBank sequences using Hirudo medicinalis as an outgroup. The monophyly of these obtained genera indicated overall similarity at species level. Today, species like Amynthas, Metaphire and Pheretima have worm diversity in the form of pheretimoid earthworms, which dates to the Late Miocene (11.2-5.3 Mya) and the Pliocene (5.3-2.4 Mya). Compared to all relevant pheretimoid species, genetic p-distance values ranged from 0.0% to 0.57% (less than 1%). These low range values demonstrated that both genera Metaphire and Amynthas, supported the theory, which states that there are shared similarities among the species, despite different morphology. The current study is the first attempt in Pakistan to identify earthworms through DNA barcoding thus providing a genomic stamp. The work explored the significance of COI gene sequences to construct molecular tools that will be useful to overcome the different obstacles in morphologically similar earthworm identification and their phylogenetic study. [ABSTRACT FROM AUTHOR]

The Fritillaria is an extremely complicated genus in taxonomy and phylogeny, which contains numerous medicinal species in China. Both traditional characteristic-based taxonomy and universal DNA barcodes (ITS, trnH-psbA, and rbcL) are difficult to effectively identify the species. Here, we generated a large dataset of chloroplast genomes from multiple accessions per species of Fritillaria to evaluate their effectiveness in species discrimination. Moreover, phylogeny of species in China was explored based on the complete chloroplast genomes, and then divergence times of each node were estimated. The results showed that all 21 species in Fritillaria here (including two suspicious species) could be correctly discriminated using cpDNA genomes except F. cirrhosa, which suggested that DNA super-barcode could greatly enhance species discriminatory resolution for complicated genera. Furthermore, four regions (ycf1, matK-trnG-GCC, rpoC1, and matK) gained remarkably higher resolution than that of other plastid regions, but only matK might be suitable to identify Fritillaria species in consideration of its lengths. Phylogenomic analysis showed that the subgenus Fritillaria in China was divided into four major clades with obvious geographic structure. Among them, Clade I, mainly distributed in southwest China, was a young and complicated group. Moreover, according to the analysis, taxonomic treatments of the two suspicious species, namely “F. omeiensis” and “F. hupehensis” in Flora of China (2000) are questionable and might need further revision. Molecular dating revealed that both origin and divergence of subgenus Fritillaria, as well as its four major clades, were significantly associated with geological and climatic fluctuations during the Middle to Late Miocene. This study would enrich case studies of DNA super-barcode and provide new insights on speciation, lineage diversification, and biogeography of the Fritillaria in China.

The early-diverging eudicot family Berberidaceae is composed of a morphologically diverse assemblage of disjunctly distributed genera long praised for their great horticultural and medicinal values. However, despite century-long studies, generic delimitation of Berberidaceae remains controversial and its tribal classification has never been formally proposed under a rigorous phylogenetic context. Currently, the number of accepted genera in Berberidaceae ranges consecutively from 13 to 19, depending on whether to define Berberis, Jeffersonia, and Podophyllum broadly, or to segregate these three genera further and recognize Alloberberis, Mahonia, and Moranothamnus, Plagiorhegma, and Dysosma, Diphylleia, and Sinopodophyllum, respectively. To resolve Berberidaceae’s taxonomic disputes, we newly assembled 23 plastomes and, together with 85 plastomes from the GenBank, completed the generic sampling of the family. With 4 problematic and 14 redundant plastome sequences excluded, robust phylogenomic relationships were reconstructed based on 93 plastomes representing all 19 genera of Berberidaceae and three outgroups. Maximum likelihood phylogenomic relationships corroborated with divergence time estimation support the recognition of three subfamilies Berberidoideae, Nandinoideae, and Podophylloideae, with tribes Berberideae and Ranzanieae, Leonticeae and Nandineae, and Podophylleae, Achlydeae, Bongardieae tr. nov., Epimedieae, and Jeffersonieae tr. nov. in the former three subfamilies, respectively. By applying specifically stated criteria, our phylogenomic data also support the classification of 19 genera, recognizing Alloberberis, Mahonia, and Moranothamnus, Plagiorhegma, and Diphylleia, Dysosma, and Sinopodophyllum that are morphologically and evolutionarily distinct from Berberis, Jeffersonia, and Podophyllum, respectively. Comparison of plastome structures across Berberidaceae confirms inverted repeat expansion in the tribe Berberideae and reveals substantial length variation in accD gene caused by repeated sequences in Berberidoideae. Comparison of plastome tree with previous studies and nuclear ribosomal DNA (nrDNA) phylogeny also reveals considerable conflicts at different phylogenetic levels, suggesting that incomplete lineage sorting and/or hybridization had occurred throughout the evolutionary history of Berberidaceae and that Alloberberis and Moranothamnus could have resulted from reciprocal hybridization between Berberis and Mahonia in ancient times prior to the radiations of the latter two genera.