Asian Clade Research Articles

Molecular phylogeny of the subgenus Ceratotropis (genus Vigna, Leguminosae) reveals three eco-geographical groups and Late Pliocene-Pleistocene diversification: evidence from four plastid DNA region sequences.

The subgenus Ceratotropis in the genus Vigna is widely distributed from the Himalayan highlands to South, Southeast and East Asia. However, the interspecific and geographical relationships of its members are poorly understood. This study investigates the phylogeny and biogeography of the subgenus Ceratotropis using chloroplast DNA sequence data. Sequence data from four intergenic spacer regions (petA-psbJ, psbD-trnT, trnT-trnE and trnT-trnL) of chloroplast DNA, alone and in combination, were analysed using Bayesian and parsimony methods. Divergence times for major clades were estimated with penalized likelihood. Character evolution was examined by means of parsimony optimization and MacClade. Parsimony and Bayesian phylogenetic analyses on the combined data demonstrated well-resolved species relationships in which 18 Vigna species were divided into two major geographical clades: the East Asia-Southeast Asian clade and the Indian subcontinent clade. Within these two clades, three well-supported eco-geographical groups, temperate and subtropical (the East Asia-Southeast Asian clade) and tropical (the Indian subcontinent clade), are recognized. The temperate group consists of V. minima, V. nepalensis and V. angularis. The subtropical group comprises the V. nakashimae-V. riukiuensis-V. minima subgroup and the V. hirtella-V. exilis-V. umbellata subgroup. The tropical group contains two subgroups: the V. trinervia-V. reflexo-pilosa-V. trilobata subgroup and the V. mungo-V. grandiflora subgroup. An evolutionary rate analysis estimated the divergence time between the East Asia-Southeast Asia clade and the Indian subcontinent clade as 3·62 ± 0·3 million years, and that between the temperate and subtropical groups as 2·0 ± 0·2 million years. The findings provide an improved understanding of the interspecific relationships, and ecological and geographical phylogenetic structure of the subgenus Ceratotropis. The quaternary diversification of the subgenus Ceratotropis implicates its geographical dispersal in the south-eastern part of Asia involving adaptation to climatic condition after the collision of the Indian subcontinent with the Asian plate. The phylogenetic results indicate that the epigeal germination is plesiomorphic, and the germination type evolved independently multiple times in this subgenus, implying its limited taxonomic utility.

Consistent association of fungus Fusarium mangiferae Britz with mango malformation disease in Pakistan

Mango malformation disease (MMD) deforms the natural shape of panicles and shoots. The disease incitant is of great concern due to its complexity and mode of infection. Recently, a new species Fusarium mangiferae Britz was confirmed as the etiological agent of MMD in African and Asian clade. There was a need to confirm the fungus in other Asian countries. We investigated the association of F. mangiferae with malformed branches of five exotic and five indigenous cultivars of Mangifera indica L. in Pakistan. F. mangiferae proved to be the dominant fungus hosting majority of the malformed tissues. Among the indigenous cultivars, maximum tissue infection of 96.66% was found in cultivar Anwar Rataul and minimum was found in cultivar Late Chaunsa (48.33%). In exotic ones, maximum and minimum infections of 97.33 and 70.67% were noted in the cultivars Sensation and Pop, respectively. Light and transmission electron microscopy proved helpful in investigating the morphological matrix and ultrastructure of the propagules of fungus F. mangiferae.

Systematics of Dendrobiinae (Orchidaceae), with special reference to Australian taxa

The systematics of subtribe Dendrobiinae, Dendrobium, and Australian dendrobiums in particular, are reviewed. Molecular approaches have delimited the subtribe, established Asian and Australasian clades and clarified relationships at some levels within them. At most lower taxonomic levels within Dendrobium s.l., resolution has been partial. Morphological and molecular phylogenetics indicate that Dendrocoryne, Rhizobium and some other sections are not monophyletic, with morphological analyses providing the greatest resolution into groups corresponding with biogeography. For most sections, sampling is too incomplete to determine relationships and monophyly. Distribution, pollination syndromes, breeding systems, fertility and specialized anatomical features contribute little to classification. Natural hybrids are more common than previously stated and may have played a role in the high level of homoplasy and evolution of Australian epiphytes. There is little support for splitting Dendrobium into many genera and species based on terminal clades. The evidence is interpreted as favouring recombination of Cadetia, Flickingeria and Diplocaulobium within the conserved broad genus Dendrobium. Nomenclatural stability is retained in continuing to use the long-held subgeneric sectional classification, including many of the sections of Schlechter, and infraspecific ranks of subspecies and varieties. In Dendrocoryne, Thelychiton, Tropilis and Tetrabaculum are rejected, as is Dockrillia in Rhizobium. Proposals to elevate infraspecific taxa to species level for variable species complexes are not supported by current morphological or molecular data based on slowly evolving DNA regions. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 166, 105–126.

Genetic analysis of the matrix and non-structural genes of equine influenza virus (H3N8) from epizootic of 2008–2009 in India

India faced an epizootic of equine influenza in 2008–2009. The isolated viruses were typed as H3N8 and grouped with the clade 2 viruses of Florida sublineage on the basis of haemagglutinin (HA) gene sequence analysis. This report describes the genetic analysis and selection pressure of matrix (M) and non-structural 1 (NS1) genes of the Indian isolates. All isolates shared 98.41% and 99.54% homology with other clade 2 viruses of Asian origin for M1 and M2 amino acid (aa) sequences, respectively. There were 3 and 4 unique aa residue changes respectively in M1 and M2 proteins in all Asian isolates. Phylogenetic analysis revealed clustering of Indian and Chinese isolates in a separate group designated here as Asian clade for M gene. Indian and Chinese isolates shared homology ranging from 98.17% to 99.08% at aa level. The M and NS1 genes were under negative selection pressure with estimated magnitude of pressure ( ω) 0.054, 0.581 and 0.30 for M1, M2 and NS1, respectively.

Pseudotsuga tanaiiHuzioka from the earliest Miocene Shichiku Flora of northeast Japan: Systematics and ecological conditions

The earliest fossil record of the genus Pseudotsuga (Pinaceae) in Asia, Pseudotsuga tanaii Huzioka, was reexamined with additional materials of seeds, leaves, cones, and twigs from the earliest Miocene Shichiku Flora of the Joban area, northeast Japan. These specimens were restudied to better understand the relationship of these fossils with the extant and fossil species from Asia. Pseudotsuga tanaii not only shows characters common to the modern species in East Asia, but also yields similar characters seen in the American clade. Thus, it could be an ancestral taxon of the Asian clade, which appeared before the diversification of the East Asian species. In contrast to the extant Pseudotsuga species growing under warm-temperate climate conditions at middle to high elevations in the mountains, Pseudotsuga tanaii appears to have been associated with lowland vegetation growing at lake margins. Forest vegetation associated with the species is equivalent to the Mixed Northern Hardwood forest, which develops under cooler climatic conditions. The inferred habitat of Pseudotsuga tanaii and its age support the hypothesis based on molecular phylogeny and morphological analyses that the genus originated in the higher latitudes during the early Paleogene and migrated south following the climatic deterioration during the late Paleogene.

Further resolution of porcine phylogeny in Southeast Asia by Thai mtDNA haplotypes

The mtDNA control region of 72 Thai native pigs and 11 Thai wild boars indigenous to Northern Thailand was comparatively sequenced. In total, 36 nucleotide variations that accounted for 24 haplotypes have been described (TNH01 to TNH20 and TWH01 to TWH04). These haplotypes and further publicly available mtDNA haplotypes were used to assess phylogenetic relationships. Twenty-three of the 24 haplotypes became integrated into the Asian clade of the phylogenetic tree and eight of them recapitulated another major cluster of haplotypes within this clade (Thai haplogroup, THG). Only haplotype TNH01 fit in with the European clade of the phylogenetic tree. An additional analysis using 510 bp of the mtDNA incorporated the THG haplotypes in to clade MTSEA (mountainous and Southeast Asian distribution) to form haplogroup MTSEA-THG. Recently, MTSEA was renamed in MC3. MC3 contains only signatures of pigs scattered across the Indo-Burma Biodiversity Hotspot (IBBH), a region including Thailand to the Kra Isthmus. Here we propose a putative independent porcine domestication event in South-east Asia (SEA). All haplotypes of haplogroup MTSEA-THG have revealed unique and previously unknown nucleotide signatures at positions 24 (nucleotide A) and at positions 183 (nucleotide C) that differentiate them from all other porcine mtDNA haplotypes.

Varicella Zoster Disease of the Central Nervous System: Epidemiological, Clinical, and Laboratory Features 10 Years after the Introduction of the Varicella Vaccine

Since the introduction of live attenuated varicella zoster virus (VZV) vaccine in 1995 there has been a significant reduction in varicella incidence and its associated complications, but the impact on VZV-associated central nervous system (CNS) disease has not been assessed. In this descriptive study we evaluated patients referred to the California Encephalitis Project from 1998 to 2009 with VZV PCR-positive cerebrospinal fluid (CSF). Epidemiological, clinical, and laboratory data were collected using a standardized case form. Specimens were genotyped using multi-single nucleotide polymorphism (SNP) analysis. Twenty-six specimens were genotyped from patients 12-85 years of age (median, 46 years). Clinical presentations included meningitis (50%), encephalitis (42%), and acute disseminated encephalomyelitis (ADEM) (8%). Only 11 patients (42%) had a concomitant herpes zoster rash. Genotype analysis identified 20 European Group (Clade1, Clade 3) strains; 4 Asian (Clade 2) strains, and 2 Mosaic Group (Clade 4, Clade VI) strains. One specimen was recognized as vaccine strain by identifying vaccine-associated SNPs. VZV continues to be associated with CNS disease, with meningitis being the most frequent clinical presentation. CNS VZV disease often presented without accompanying zoster rash. Sequencing data revealed multiple genotypes, including 1 vaccine strain detected in the CSF of a young patient with meningitis.

Mitochondrial DNA diversity in wild boar from the Primorsky Krai Region (East Russia)

We have studied the cytochrome B gene and control region DNA variability in 14 wild boars from the Primorsky Region, in the far east corner of Russia. Variability was low (π = 0.00248 overall) compared with the usual estimates in these loci, indicating that this is a rather closed population. Seven haplotypes were found, and one was identical to a Chinese wild boar. Phylogeographically, the sequences clustered among several Asian clades, primarily Chinese domestic pigs and Japanese and Chinese wild boars, and are positioned within the D2 clade reported by Larson et al. [Science307, 2005; 1618]. Although North Korean pigs should be studied, our data suggest that the Primorsky mtDNA signature is absent from domestic pigs. Sequences are available through GenBank identifiers HM010461-HM010488.

Evolutionary relationships and divergence times among the native rats of Australia

BackgroundThe genus Rattus is highly speciose and has a complex taxonomy that is not fully resolved. As shown previously there are two major groups within the genus, an Asian and an Australo-Papuan group. This study focuses on the Australo-Papuan group and particularly on the Australian rats. There are uncertainties regarding the number of species within the group and the relationships among them. We analysed 16 mitochondrial genomes, including seven novel genomes from six species, to help elucidate the evolutionary history of the Australian rats. We also demonstrate, from a larger dataset, the usefulness of short regions of the mitochondrial genome in identifying these rats at the species level.ResultsAnalyses of 16 mitochondrial genomes representing species sampled from Australo-Papuan and Asian clades of Rattus indicate divergence of these two groups ~2.7 million years ago (Mya). Subsequent diversification of at least 4 lineages within the Australo-Papuan clade was rapid and occurred over the period from ~ 0.9-1.7 Mya, a finding that explains the difficulty in resolving some relationships within this clade. Phylogenetic analyses of our 126 taxon, but shorter sequence (1952 nucleotides long), Rattus database generally give well supported species clades.ConclusionsOur whole mitochondrial genome analyses are concordant with a taxonomic division that places the native Australian rats into the Rattus fuscipes species group. We suggest the following order of divergence of the Australian species. R. fuscipes is the oldest lineage among the Australian rats and is not part of a New Guinean radiation. R. lutreolus is also within this Australian clade and shallower than R. tunneyi while the R. sordidus group is the shallowest lineage in the clade. The divergences within the R. sordidus and R. leucopus lineages occurring about half a million years ago support the hypotheses of more recent interchanges of rats between Australia and New Guinea. While problematic for inference of deeper divergences, we report that the analysis of shorter mitochondrial sequences is very useful for species identification in rats.

Identification and Characterization of a Novel Etiological Agent of Mango Malformation Disease in Mexico, Fusarium mexicanum sp. nov.

The primary objective of this study was to characterize Fusarium spp. associated with the economically devastating mango malformation disease (MMD) in Mexico. In all, 142 Fusarium strains were isolated from symptomatic mango inflorescences and vegetative tissues in eight geographically diverse Mexican states from 2002 through 2007. Initially, all the Mexican isolates were screened for genetic diversity using appolymerase chain reaction and random amplified polymorphic DNA markers and were grouped into seven distinct genotypes. Based on results of these analyses, evolutionary relationships and species limits of the genetically diverse MMD-associated Fusarium spp. were investigated using multilocus DNA sequence data and phylogenetic species recognition. Maximum parsimony analyses of a five-locus data set comprising 5.8 kb of aligned DNA sequence data indicated that at least nine phylogenetically distinct Fusarium spp. within the Gibberella fujikuroi species complex are associated with MMD, including one species within the African clade (Fusarium pseudocircinatum), two species within the Asian clade (F. mangiferae and F. proliferatum), and at least six species within the American clade (F. sterilihyphosum and five undescribed Fusarium spp.). Molecular phylogenetic analyses indicate that a novel genealogically exclusive lineage within the American clade was the predominant MMD associate in Mexico. This new Fusarium sp. caused MMD and could be distinguished from all other known species morphologically by the production of mostly sterile, coiled hyphae which are typically associated with sporodochial conidiophores together with unbranched or sparsely branched aerial conidiophores. Koch's postulates were completed for isolates of the new species on nucellar seedlings of mango cv. Ataulfo. This pathogen is formally described herein as F. mexicanum.

Phylogenetic relationships within the cahirinus-dimidiatus group of the genus Acomys (Rodentia: Muridae): new mitochondrial lineages from Sahara, Iran and the Arabian Peninsula

Spiny mice belonging to the cahirinus-dimidiatus group of the genus Acomys have become a widely used model in physiology and behaviour. To improve current knowledge concerning the phylogeny of this taxon, we analysed 24 samples from Libya, Chad, Egypt, Jordan, Cyprus, Crete, Turkey, Yemen and Iran. We sequenced the whole mitochondrial control region and part of the flanking tRNA genes for a total length of 986 to 996 bp and described 22 haplotypes. Our results confirmed that the Afro-Mediterranean and Asian clades are clearly distinct (p-distance = 6-8.1%). The former clade corresponds to A. cahirinus sensu lato (i.e. including also the Cretan A. minous, Cypriot A. nesiotes and Turkish A. cilicicus). Haplotypes of A. cahirinus from the E Sahara (S Egypt, SW Libya, N Chad) grouped with those of A. cilicicus and A. minous (p-distance ≤ 2.2%), while haplotypes of A. nesiotes grouped with one haplotype representing the commensal A. cahirinus from Cairo (p-distance = 1.2%). Close similarity among haplotypes from mainland Africa and NE Mediterranean (clade A. cahirinus sensu stricto) support the hypothesis that ancestors of A. nesiotes, A. cilicicus and A. minous dispersed most probably as commensal populations, thus questioning their status of valid species. The most surprising finding was the considerable genetic variation in Asia. In addition to a haplogroup from Sinai and Jordan (corresponding to A. dimidiatus sensu stricto), we detected two previously unknown haplogroups, from Yemen and Iran + United Arab Emirates. These clades are fairly distinct and separate species/subspecies status of these animals might be further considered.

Phylogeny of the Linnaea clade: Are Abelia and Zabelia closely related?

Phylogenetic investigations based on molecular and morphological data have improved our understanding of Dipsacales phylogeny dramatically over the past 20 years. The Linnaea clade, however, has mostly been neglected and Zabelia has rarely been included in previous studies. We present the results of a molecular investigation including nine Abelia and five Zabelia species based on nuclear (ITS) and plastid (trnK, matK, atpB-rbcL, trnL-F) sequence data using maximum parsimony, Bayesian inference, and maximum likelihood. Our results indicate that Abelia is paraphyletic and possibly polyphyletic. The genus falls apart into a Mexican clade, corresponding to Abelia section Vesalea, and an Asian clade (excluding A. spathulata), corresponding to Abelia section Abelia. A close relationship between Zabelia and other members of the traditional Linnaea clade is not recovered by our analyses. Instead, Zabelia is associated with either the Morina or the Valeriana clade. Support for a monophyletic Linnaea clade without Zabelia is strong.

The phylogenetic position of milkweeds (Apocynaceae subfamilies Secamonoideae and Asclepiadoideae): Evidence from the nucleus and chloroplast

AbstractThe nuclear gene phytochrome A (PHYA) from 71 species of crown clade Apocynaceae (subfamilies Asclepiadoideae, Secamonoideae, Periplocoideae, and four lineages of Apocynoideae) and outgroups is used to (1) test the chloroplast phylogeny that places the African tribe Baisseeae, with solitary pollen grains, as sister to the pollinia‐bearing milkweeds (Secamonoideae plus Asclepiadoideae); (2) resolve the position of tetrad‐bearing Periplocoideae, the proposed milkweed sister group based on morphology; (3) place the enigmatic Dewevrella; and (4) clarify relationships of the three other primary crown clade lineages: Rhabdadenia, New World clade, and Asian clade. Separate analyses of PHYA and chloroplast sequences agree in placing an African monad‐bearing clade (Baisseeae plus Dewevrella) as the sister group of the milkweeds. Combined PHYA and chloroplast datasets under parsimony and maximum likelihood reject Periplocoideae as the milkweed sister group with statistical significance. Rhabdadenia is placed as sister to the rest of the crown clade, consistent with aspects of its floral morphology and wood anatomy, but without statistical support. Other relationships among the primary crown clade Apocynaceae lineages are also not supported statistically, but power analysis indicates that four to eight times as many characters (26,376–52,752 aligned positions) will be sufficient for a robust estimate.

The phylogeography of Indoplanorbis exustus (Gastropoda: Planorbidae) in Asia.

BackgroundThe freshwater snail Indoplanorbis exustus is found across India, Southeast Asia, central Asia (Afghanistan), Arabia and Africa. Indoplanorbis is of economic importance in that it is responsible for the transmission of several species of the genus Schistosoma which infect cattle and cause reduced livestock productivity. The snail is also of medical importance as a source of cercarial dermatitis among rural workers, particularly in India. In spite of its long history and wide geographical range, it is thought that Indoplanorbis includes only a single species. The aims of the present study were to date the radiation of Indoplanorbis across Asia so that the factors involved in its dispersal in the region could be tested, to reveal potential historical biogeographical events shaping the phylogeny of the snail, and to look for signs that I. exustus might be polyphyletic.ResultsThe results indicated a radiation beginning in the late Miocene with a divergence of an ancestral bulinine lineage into Assam and peninsular India clades. A Southeast Asian clade diverged from the peninsular India clade late-Pliocene; this clade then radiated at a much more rapid pace to colonize all of the sampled range of Indoplanorbis in the mid-Pleistocene.ConclusionsThe phylogenetic depth of divergences between the Indian clades and Southeast Asian clades, together with habitat and parasitological differences suggest that I. exustus may comprise more than one species. The timescale estimated for the radiation suggests that the dispersal to Arabia and to Southeast Asia was facilitated by palaeogeographical events and climate change, and did not require human involvement. Further samples from Afghanistan, Africa and western India are required to refine the phylogeographical hypothesis and to include the African Recent dispersal.

First report of Chrysoporthe cubensis from Eucalyptus in Ghana

During disease surveys of Eucalyptus grandis, E. camaldulensis and E. dagambae in the Ashanti, Central and Eastern Provinces of Ghana in February 2007 stem cankers on mature E. dagambae, resembling that caused by species of Chrysoporthe, were observed in a single compartment near Kumasi. Infection was visible only as stem cankers, characterized by cracked bark, mostly at the bases of trees, bearing long necked fungal fruiting bodies, visible with the naked eye or a hand lens. Some cankers girdled the entire tree. Orange spore masses were transferred aseptically from the tips of the fruiting bodies to malt extract agar in Petri dishes. Fungal isolates were identified using DNA sequence data of the rDNA (ITS, 5·8S) (GenBank Accession No. GQ292541) and beta tubulin gene regions (GU014577). Isolates from Ghana represent C. cubensis, grouping with isolates in the South American clade and similar to isolates from the Republic of Congo and Cameroon (Roux et al., 2003; Gryzenhout et al., 2004). This is in contrast to C. cubensis isolates from East Africa which group in the Asian clade (Nakabonge et al., 2006). Sixteen isolates of C. cubensis, obtained from 16 separate trees, were assessed for their phenotypic diversity. This was done by vegetative compatibility grouping (VCG) of single hyphal tip isolates on oatmeal agar. All isolates, except one, resided in a single VCG type, supporting suggestions that C. cubensis in West Africa has been introduced (Wingfield, 2003). Two isolates of C. cubensis from Ghana were inoculated into the stems of ten trees each of a 1-year-old E. grandis clone in the greenhouse. After 6 weeks lesions had formed in the bark and cambium, stretching into the xylem of inoculated trees. Chrysoporthe cubensis was successfully re-isolated. No lesions were formed in the control inoculations. This is the first report of C. cubensis from Ghana and attacking E. dagambae, expanding the host and geographic range of this possibly introduced pathogen (Nakabonge et al., 2006) in Africa. The National Research Foundation of South Africa (NRF) funded the research.

Molecular phylogeny of the genus Vitis (Vitaceae) based on plastid markers

This work represents the first molecular phylogeny of the economically important genus Vitis, an important genetic resource for breeding in grapevine, Vitis vinifera. • A molecular phylogeny of Vitis using a combined data set of three noncoding regions of the plastid DNA genome was constructed from 47 accessions covering 30 species of Vitis. The data for the trnL-F marker were combined with previously published data across the Vitaceae. • The molecular phylogeny demonstrated monophyly of the genus Vitis. Based on the combined analysis of three genes, Vitis is split into three clades that mirror the continental distribution of these accessions. The diversity is highest in the Asian clade, but the general genetic distances across taxa from different continents are relatively small. • The findings support a relatively recent and intense gene flow between East Asia and North America and the possible impact of hybridization on the evolution of the genus Vitis. Taxon identity in important stock collections should be screened carefully because roughly 10% of the accessions analyzed in the present study had been misidentified.

South Asia supports a major endemic radiation of Hemidactylus geckos

Hemidactylus geckos are a species-rich component of many tropical lizard assemblages. We sampled deeply among tropical Asian, and especially South Asian, taxa and used a multi-gene approach to establish the affinities of Indian and Sri Lankan Hemidactylus and to evaluate the monophyly of previously proposed taxa within the genus. There is only weak support for the monophyly of tropical Asian Hemidactylus as a whole, but two strongly supported subclades were retrieved: the bowringii group is a predominantly East Asian clade that reaches South Asia only peripherally; the brookii group is a morphologically diverse clade that represents a previously unrecognized, species-rich (25 species), chiefly South Asian radiation. Deep genetic divergences support the specific recognition of three Sri Lankan taxa previously regarded as subspecies of mainland forms and validate H. subtriedrus as a species distinct from H. triedrus. Unlike several other vertebrate groups, Sri Lankan Hemidactylus do not represent a single insular radiation. Rather, each of six Sri Lankan species reached the island independently from different continental sources. There have been extensive Quaternary land connections between India and Sri Lanka but sister-species pairs of Hemidactylus on the two land masses diverged from one another much earlier, probably in the mid-Miocene.

Revision and cladistic analysis of the jumping spider genus Onomastus (Araneae: Salticidae)

The jumping spider genus Onomastus Simon, 1900 is revised. Four new species: Onomastus indra sp. nov., Onomastus kaharian sp. nov., Onomastus pethiyagodai sp. nov., and Onomastus rattotensis sp. nov. are described. Parsimony analysis of 26 morphological characters supported the monophyly of Onomastus. Lyssomanes is sister to Onomastus. Onomastus separates into two clades: the widespread South-East Asia clade and the South Asia clade. The South Asia clade is restricted to the Sri Lanka–Western Ghats biodiversity hotspot. Species of the South Asia clade appear to be spot endemics, highly in danger of extinction because of habitat loss and climate change. Male palps are complex and species-specific, suggesting rapid divergent evolution. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159, 711–745.

Phylogeographic relationships of the southern green stink bug Nezara viridula (Hemiptera: Pentatomidae)

Abstract The sequences of 16S rDNA, cytochrome oxidase subunit I (COI) and cytochrome b (Cyt b) genes from nine field collections (seven provinces in China: Guangxi, Hubei, Guangdong, Guizhou, Zhejiang, Hunan, Jiangxi, and also southern and northern part of Iran), plus the sequences of Africa, Europe, Americas and Japan obtained form GenBank were used to re‐analyse the genetic variation in the southern green stink bug Nezara viridula (Linnaeus). The phylogeographic re‐analysis by using four algorithms (NJ, MP, ML and Bayesian) showed three main lineages. The Iranian haplotypes fell into lineage II formed from Europe and America, rather than in lineage III from Asia; the Chinese haplotypes fell into the Asian clade. Our results suggested that African and non‐African gene pools have been isolated since the Miocene era with the molecular clock calibrations for Heteroptera mtDNA, and not since the Pliocene as mentioned previously. The corresponding age of the separation of the eastern and western Asia clades is estimated to be 4.0–1.6 million years ago, coinciding with the Pliocene–Pleistocene epoch and with acute rising events in the Tibet Plateau locates in the western China, which may have formed the barriers observed today.

Reticulate evolution, cryptic species, and character convergence in the core East Asian clade of Gaultheria (Ericaceae)

Phylogenetic relationships of 84 samples representing 30 species in the core East Asian clade of the wintergreen group of Gaultheria (Angiospermae: Ericaceae: Gaultherieae) were estimated from separate and combined DNA sequence data from five genic regions (ITS, matK, rpl16, trnL–trnF, and trnS–trnG) with parsimony, likelihood and Bayesian analyses. Two major clades were recovered, one comprising several sections and series with leaves generally more than 1cm long [the ser. Leucothoides sensu lato (s.l.) clade] and another comprising the species of ser. Trichophyllae, with leaves generally less than 1cm long. The ITS region yielded little phylogenetic resolution, whereas in the combined chloroplast analysis the samples from individual morphospecies in both clades were often nonmonophyletic. This was postulated to result from reticulate evolution in the ser. Leucothoides s.l. clade, particularly in two specific cases of hybridization and a crown clade with likely chloroplast capture following localized introgression. In the ser. Trichophyllae clade, such nonmonophyly was largely attributed to cryptic species and character convergence resulting at least partly from extreme morphological reduction. The relatively low-elevation habitats in which the species of the ser. Leucothoides s.l. clade generally grow are thought to have promoted opportunities for sympatry and reticulation, whereas the high-alpine habitats of ser. Trichophyllae are more likely to have spawned isolated populations and narrow endemism. As in other Sino-Himalayan plant groups, overall low sequence divergence and reticulate evolution suggest rapid radiation in the core East Asian clade of Gaultheria.