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1.
Studies of phylogenetic relationships among cypresses of the Old World (Cupressus; Cupressaceae) have been plagued by unresolved relationships, poor branch support, and conflict between data sets and methods of analysis. In this study, we combined 5.4 kb of aligned DNA sequence and 157 binary characters with previously published data in examining phylogenetic relationships among Cupressus species. Bayesian and parsimony analysis of the combined data or of the nuclear data alone always recovered three principal clades of Cupressus; however, tests of phylogenetic incongruence could not distinguish between competing relationships among the three principal Cupressus lineages. In contrast, incongruence tests often found statistically significant conflict between the nuclear and plastid data, particularly with respect to the placement of C. chengiana. Consistent with previous studies and prevailing taxonomic opinion, we find C. darjeelingensis more closely related to cypresses of the New World (Hesperocyparis). In contrast, we placed accessions of C. assamica and C. tonkinensis, two putatively Old World species suggested to be misidentified New World taxa by some authors, within well-supported Old World clades. Statistical analysis of genetic distances suggests instances in which taxa recognized as distinct species by some authors are identical or nearly so and may best be considered a single taxon. Conversely, we identify instances in which infraspecific taxa are more distantly related to one another than those traditionally recognized as distinct species. Factors confounding cypress taxonomies, including poor morphological differentiation, misidentification, and the use of accessions of questionable provenance, are discussed. 相似文献
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Datura (Solanaceae) is a small genus of plants that, for long, was thought to occur naturally in both the New and Old Worlds. However, recent studies indicate that all species in the genus originated in the Americas. This finding has prompted the conclusion that no species of Datura could have been present in the Old World prior to its introduction there by Europeans in the early 16th century CE. Further, the textual evidence traditionally cited in support of a pre-Columbian Old World presence of Datura species is suggested to be due to the misreading of classical Greek and Arabic sources. As a result, botanists generally accept the opinion that Datura species were transferred into the Old World in the post-Columbian period. While the taxonomic and geographic evidence for a New World origin for all the Datura species appears to be well supported, the assertion that Datura species were not known in the Old World prior to the 16th century is based on a limited examination of the pre-Columbian non-Anglo sources. We draw on old Arabic and Indic1 texts and southern Indian iconographic representations to show that there is conclusive evidence for the pre-Columbian presence of at least one species of Datura in the Old World. Given the systematic evidence for a New World origin of the genus, the most plausible explanation for this presence is a relatively recent but pre-Columbian (probably first millennium CE) transfer of at least one Datura species, D. metel, into the Old World. Because D. metel is a domesticated species with a disjunct distribution, this might represent an instance of human-mediated transport from the New World to the Old World, as in the case of the sweet potato (Ipomoea batatas). 相似文献
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The figwort genus Scrophularia (Scrophulariaceae), widespread across the temperate zone of the Northern Hemisphere, comprises about 250 species and is a taxonomically challenging lineage displaying large morphological and chromosomal diversity. Scrophularia has never been examined in a large-scale phylogenetic and biogeographic context and represents a useful model for studying evolutionary history in the context of reticulation. A comprehensively sampled phylogeny of Scrophularia was constructed, based on nuclear ribosomal (ITS) and plastid DNA sequences (trnQ-rps16 intergenic spacer, trnL-trnF region) of 147 species, using Bayesian inference and maximum likelihood approaches. Selected individuals were cloned. A combination of coding plastid indels and ITS intra-individual site polymorphisms, and applying Neighbor-Net and consensus network methods for adequate examination of within-dataset uncertainty as well as among-dataset incongruence, was used to disentangle phylogenetic relationships. Furthermore, divergence time estimation and ancestral area reconstruction were performed to infer the biogeographic history of the genus. The analyses reveal significant plastid-nuclear marker incongruence and considerable amounts of intra-individual nucleotide polymorphism in the ITS dataset. This is due to a combination of processes including reticulation and incomplete lineage sorting, possibly complicated by inter-array heterogeneity and pseudogenization in ITS in the presence of incomplete concerted evolution. Divergence time estimates indicate that Scrophularia originated during the Miocene in Southwestern Asia, its primary center of diversity. From there, the genus spread to Eastern Asia, the New World, Europe, Northern Africa, and other regions. Hybridization and polyploidy played a key role in the diversification history of Scrophularia, which was shaped by allopatric speciation in mountainous habitats during different climatic periods. 相似文献
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Salvia subg. Calosphace (Lamiaceae, Lamiales) is a highly diverse clade endemic to the New World. The phylogenetic relationships of Calosphace have been previously investigated using DNA sequences of nuclear ITS region and plastid psbA–trnH intergenic spacer, but the resulting trees lack resolution and support for many clades. The present paper reassesses the phylogenetic relationships of subgenus Calosphace, including a broader taxon sampling, with a special focus on representing previously unsampled sections, and using an additional plastid marker (trnL–trnF region). Our results show increased resolution and overall patterns of support, recovering ten main clades. Within core Calosphace, the most inclusive of these main clades, 17 new subclades were identified. Of the 42 sections for which more than one species was analysed, only 12 are monophyletic. Our biogeographical analysis identified at least twelve migrations to South America from Mexican and Central American lineages, in agreement with previous suggestions of multiple origins of South American Calosphace diversity. This analysis also confirmed a colonization of the Antilles by Andean lineages. The reconstruction of ancestral states of pollination syndromes showed multiple shifts to ornithophily from melittophily and one reversal to the latter. 相似文献
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Avinash R. Gholave Kiran D. Pawar Shrirang R. Yadav Vishwas A. Bapat Jyoti P. Jadhav 《Physiology and Molecular Biology of Plants》2017,23(1):155-167
Plastid DNA markers sequencing and DNA fingerprinting approaches were used and compared for resolving molecular phylogeny of closely related, previously unexplored Amorphophallus species of India. The utility of individual plastid markers namely rbcL, matK, trnH–psbA, trnLC–trnLD, their combined dataset and two fingerprinting techniques viz. RAPD and ISSR were tested for their efficacy to resolves Amorphophallus species into three sections specific clades namely Rhaphiophallus, Conophallus and Amorphophallus. In the present study, sequences of these four plastid DNA regions as well as RAPD and ISSR profiles of 16 Amorphophallus species together with six varieties of two species were generated and analyzed. Maximum likelihood and Bayesian Inference based construction of phylogenetic trees indicated that among the four plastid DNA regions tested individually and their combined dataset, rbcL was found best suited for resolving closely related Amorphophallus species into section specific clades. When analyzed individually, rbcL exhibited better discrimination ability than matK, trnH–psbA, trnLC–trnLD and combination of all four tested plastid markers. Among two fingerprinting techniques used, the resolution of Amorphophallus species using RAPD was better than ISSR and combination of RAPD +ISSR and in congruence with resolution based on rbcL. 相似文献
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We anatomically characterized the aerial stems of the genus Dioscorea and evaluated the use of these anatomical characteristics to better understand the taxonomy, systematics, and diversity of the component species in the neotropics. Fragments of the aerial stems of 23 species were collected for anatomical analyses utilizing conventional cytohistological techniques. Stem anatomy did not support the subgenera and neotropical sections of Dioscorea, although D. sect. Monadelpha demonstrated similar anatomical characteristics with the representatives analyzed in the present work, supporting the possible monophyletism of that section. Some New World species demonstrated characteristics described earlier for Old World species, such as two phloem units internal to the large-diameter vessels. New characters to the vascularization of new world species are described, as a single ring of vascular bundles, intercalating common and cauline bundles. Tylosoids and actinocytic stomata were the first time reported in Dioscorea, and the vascular patterns are revisited with a systematic approach. 相似文献
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The genus Myotis is unique among mammals in its high taxonomic diversity and global distribution. Their phylogenetic relationships reflect biogeographic affinities rather than phenotypes. Myotis diverged from other bats in the early Miocene, with a subsequent split between Old and New World lineages about 19 million years ago. Similar ecomorphs (‘Leuconoe’ [near-water hunters], ‘Myotis’ [gleaners], ‘Selysius’ [aerial hawkers]) emerged independently in different lineages of Myotis. We retrieved the probable ancestral ecomorph for each lineage. Phenetic diversity was estimated from the analysis of body and skull traits. It seems that evolution of Myotis fluctuated between ‘Leuconoe’, ‘Selysius’, and larger ‘Myotis’. 相似文献
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Tor Erik Brandrud Geert Schmidt-Stohn Kare Liimatainen Tuula Niskanen Tobias Guldberg Frøslev Karl Soop Dimitar Bojantchev Ilkka Kytövuori Thomas Stjernegaard Jeppesen Francesco Bellù Günter Saar Bernhard Oertel Tahir Ali Marco Thines Bálint Dima 《Mycological Progress》2018,17(12):1323-1354
Cortinarius is one of the most species-rich genera of mushroom-forming fungi. Based on phylogenetic and morphological evidence, Cortinarius, sect. Riederi, is introduced at sectional level (= subsect. Riederi sensu Brandrud & Melot). The taxonomy, phylogeny, ecology and distribution of not only mainly European but also including some North American taxa of this section are treated, which includes nine species and two varieties. Of these, three taxa are described as new (C. burlinghamiae, C. pallidoriederi and C. argenteolilacinus var. dovrensis). The sect. Riederi species possess morphological features similar to Phlegmacium group(s) and forms a phylogenetically isolated lineage, with no supported affinity to other phlegmacioid groups. Three taxa are known from both Europe and North America, two species are known only from North America and five only from Europe. Altogether, eight of the ten taxa are associated with conifers or northern (boreal-subalpine) deciduous trees (Betula spp.). Only two species occur in more temperate forests (Fagus forests), and no species have so far been found in thermophilous Quercus forests 相似文献
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Sajeewa S.N. Maharachchikumbura Liang-Dong Guo Zuo-Yi Liu Kevin D. Hyde 《Mycological Progress》2016,15(3):22
We combined morphological and combined ITS, TUB and TEF sequence data to infer the phylogeny of the recently introduced genus Pseudopestalotiopsis. Two new species from China, Ps. camelliae from blighted leaves of Camellia sinensis and Ps. ignota from an undetermined host in China, are introduced with illustrated accounts and compared with similar taxa. Grey blight disease of tea appears to be caused by a group of fungi that constitutes a species complex. A new combination is proposed to emend the monophyly of Pseudopestalotiopsis and a species comparison is provided for taxa in the genus. 相似文献
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The phylogenetic positions of the families Campynemataceae and Corsiaceae within the order Liliales remains unclear. To date, molecular data from the plastid genome of Corsiaceae has been obtained exclusively from Arachnitis, for which alignment and phylogenetic inference has proved difficult. The extent of gene conservation among mycoheterotrophic species within Corsiaceae remains unknown. To clarify the phylogenetic position of Campynemataceae and Corsiaceae within Liliales, functional plastid-coding genes of species representing both families have been analyzed. Examination of two phylogenetic data sets of plastid genes employing parsimony, maximum-likelihood, and Bayesian inference methods strongly supported both families forming a basal clade to the remaining taxa of Liliales. The first data set consists of five functional plastid-encoded genes (matK, rps7, rps2, rps19, and rpl2) sequenced from Corsia dispar (Corsiaceae). The data set included 31 species representing all families within Liliales, as well as selected orders that are related closely to Liliales (10 outgroup species from Asparagales, Dioscoreales, and Pandanales). The second phylogenetic analysis was based on 75 plastid genes. This data set included 18 species from Liliales, representing major clades within the order, and 10 outgroup species from Asparagales, Dioscoreales, and Pandanales. In this latter data set, Campynemataceae was represented by 60 plastid-encoded genes sequenced from herbarium material of Campynema lineare. A large proportion of the plastid genome of C. dispar was also sequenced and compared to the plastid genomes of photosynthetic plants within Liliales and mycoheterotrophic plants within Asparagales to explore plastid genome reduction. The plastid genome of C. dispar is in the advanced stages of reduction, which signifies its high dependency on mycorrhizal fungi and is suggestive of a loss in photosynthetic ability. Functional plastid genes found in C. dispar may be applicable to other species in Corsiaceae, which will provide a basis for in-depth molecular analyses of interspecies relationships within the family, once molecular data from other members become available. 相似文献
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Orphanodendron is a taxonomically and geographically isolated South American genus of two species. When first described by Barneby and Grimes in 1990, the genus was placed in Leguminosae subfamily Caesalpinioideae, but that placement was doubted and the name Orphanodendron (Gr. orphanos, orphan + dendron, tree) was chosen to reflect the uncertain subfamilial relationship of the genus. In this study, nucleotide sequence data from five Orphanodendron specimens were added to 662 other, previously sampled, Leguminosae taxa representing all three currently recognized subfamilies (Caesalpinioideae, Mimosoideae and Papilionoideae) in a matK maximum parsimony analysis that resolved Orphanodendron as a member of the genistoid s.l. clade of subfamily Papilionoideae. Two additional Bayesian phylogenetic analyses with reduced taxon sampling of plastid (matK combined with trnL-F) and nuclear (ITS) loci strongly support the monophyly of Orphanodendron and unambiguously establish Orphanodendron as a member of the genistoid sensu lato clade. Although our plastid phylogenetic analysis finds relatively low support for a sister-group relationship with the African genus Camoensia, the nuclear-encoded ITS resolves Orphanodendron as sister to the Bowdichia clade with strong support and Camoensia as sister to other core genistoids. The phylogenetic resolution of Orphanodendron as a member of the genistoid s.l. legumes based on nuclear and plastid sequences will undoubtedly advance future evolutionary investigations of this Colombian endemic tropical tree genus. 相似文献
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A. S. Biakov 《Paleontological Journal》2008,42(3):232-242
New concepts of systematics and phylogeny of the Permian Inoceramus-like bivalve mollusks of the eastern part of the Boreal zone are discussed based on analysis of the group’s historical development. All taxa studied are referred to the family Kolymiidae Kusnezov, which is divided into two subfamilies, Kolymiinae and Atomodesmatinae. In the subfamily Kolymiinae, two new genera are described: Praekolymia with the type species P. archboldi sp. nov. and P. urbajtisae sp. nov., and Taimyrokolymia with the type species T. ustritskyi sp. nov. In the subfamily Atomodesmatinae, two new genera, Costatoaphanaia and Okhotodesma, are described. The development of the group is shown to be generally autochthonous with some invasions (genus Atomodesma and, probably, Trabeculatia) from extraboreal regions. 相似文献
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The genus Leucheria Lag. (Asteraceae Bercht. and J. Presl, tribe Nassauvieae Cass.) comprises 45 species and three infraspecific taxa distributed in the Andean region from southern Chile and Argentina to Peru. Six species are annual herbs. The genus has had a long taxonomic history involving the transference of species described originally under many different genera. The main objectives of this paper were to determine the phylogenetic relationships of species of Leucheria, examine the hypothesis that the ancestor of Leucheria would have originated in a forested habitat and examine the validity of nine morphologically defined evolutionary lines recognized in earlier work on the genus. Additionally we investigated whether the annual species of Leucheria are derived. We extracted DNA from leaf material for 45 taxa (94%) of Leucheria. We used Bayesian inference and plastid and nuclear genes to construct a phylogenetic hypothesis. Results show that Leucheria is monophyletic and is comprised of two main clades. One clade comprises perennial acaulescent/subacaulescent species, all with a solitary capitulum. We recognized three lineages in the second clade comprised of caulescent species that exhibit multiple capitula. Optimization of life-form over the phylogeny showed that five of the six annual species studied are derived in our tree. We conclude that the appearance of the annual habit is associated with the colonization of arid conditions in the winter rainfall coastal desert of northern Chile. Our result shows that species of Leucheria from forested habitats are derived. Discrepancies with previously recognized morphologically defined evolutionary lines were detected. 相似文献
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Yu Song Xin Yao Yunhong Tan Yi Gan Junbo Yang Richard T. Corlett 《Tree Genetics & Genomes》2017,13(6):120
Phoebe is an economically important genus from the family Lauraceae. It is widely distributed in tropical and subtropical Asia, but systematics of the genus is unclear, and currently there is no species-level phylogeny. Here, we determined the complete chloroplast genome sequences of two species with long-range PCR and next genome sequencing technologies, and identified mutation sites and highly variable regions. These highly variable sites were used to reconstruct the phylogeny. The plastomes of Phoebe sheareri and P. omeiensis were 152, 876, and 152, 855 bp, respectively. Comparative genomic analysis indicated that there are 222 mutation sites including 146 substitutions, 73 indels, and 3 microinversions in both plastomes. Fifty-six single-nucleotide changes were identified in gene-coding regions, and 45 microsatellite sites were found for use in species identification. Fourteen divergence hotspots of 38 variable regions were located. Phylogeny was reconstructed using a Bayesian and maximum likelihood approach for 12 Phoebe species and other five related Lauraceae based on 15 of the highly variable regions including accD-psaI, atpB-rbcL, ndhC-trnV, ndhF-rpl32, petA-psbJ, psaA, psbA-trnH, rbcL, rps8-rpl14, rps16-trnQ, rpl32-trnL, trnC-petN, trnL-trnF, trnS-trnG, and ycf1 indicated that variability in the chloroplast regions proposed as variable is enough to detect divergence events among 12 taxa of Phoebe, and that maybe also useful to help to elucidate further relationships among other taxa of the genus. 相似文献
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José Antonio Fernández Prieto Mauro Sanna Álvaro Bueno Sánchez Joaquín Molero-Mesa Leonardo Llorens García Eduardo Cires 《Journal of plant research》2018,131(5):747-758
The genus Pimpinella L. comprises about 150 species, being one of the largest genera within the family Apiaceae (subfamily Apioideae). Previous molecular phylogenetic studies have shown that Pimpinella is a taxonomically complex group. In this study, evolutionary relationships among representatives from Western Europe have been inferred from phylogenetic analyses of nuclear ribosomal DNA internal transcribed spacer (ITS 1 and ITS 2) and plastid sequences (trnL intron and the trnL-F spacer), with a representative sampling included (168 accessions in the ITS analysis, representing 158 species; and 42 accessions in the cpDNA analysis representing 35 taxa of Pimpinella and closely related species). All analyses resolved that Pimpinella is a non-monophyletic group, and Pimpinella’s taxa that grow in Western Europe are part of phylogenetically independent groups that correspond to three different tribes of the subfamily Apioideae: Pimpinelleae (core group), Pyramidoptereae and Smyrnieae. 相似文献
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Maxim V. Vinarski 《Biological invasions》2017,19(4):1299-1314
Physella acuta (Draparnaud, 1805) is an aquatic pulmonate snail notorious for its high invasive potential. Of New World origin, this species now occurs on all continents. The aim of this study was to trace P. acuta dispersal through the Western Palearctic starting from its first arrival in the Old World and to determine possible drivers of this process. A range of literary sources as well as some rich European malacological collections have been consulted to ascertain the dates of the first finding of P. acuta in the countries of Europe, Transcaucasia, and Central Asia and to map the most significant localities. The shell characteristics of this species are so distinctive that they almost preclude misidentification and confusion with any native species. This allows one to rely on historical records, including older sources (18th to the first half of the 19th centuries). The earliest reliable records of P. acuta in the Old World can be dated to 1742, which implies an earlier date for the first arrival of the species in Europe, possibly in the 17th century. Its introduction may be explained either by accidental dispersal mediated by humans (for example, during transport of exotic plants to European botanical gardens) or by natural causes (long-distance dispersal from the Americas to Europe). Three successive phases leading to the current invasive range of P. acuta in the Western Palearctic can be identified. The species’ current Old World range can be viewed as a result of the interaction of natural and anthropogenic factors. The human-mediated drivers of dispersal include canal building, the aquarium trade and, more recently, alteration of natural freshwater habitats. 相似文献
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Speciation is an ongoing process. Many recognized species are fully divergent from each other and their ancestors, whereas others are in earlier stages in the diversification process. Such incipient speciation may create patterns when one or a few populations are phenotypically distinct, but lack genomic level coalescence from each other or from their ancestral species. As a result, such progenitor-derivative species pairs are likely to lack reciprocal monophyly or generate paraphyletic ancestral species. Here we examine phylogenetic patterns in the Columnea strigosa (Gesneriaceae) complex to evaluate whether populations that have been named C. kucyniakii are reciprocally monophyletic with C. strigosa, its presumed ancestral species. Molecular phylogenetic results do not support reciprocal monophyly of the two species, implying that incipient speciation is occurring within the C. strigosa complex. We hereby recommend that C. kucyniakii be recognized at the specific rank despite the fact that it creates a paraphyletic C. strigosa. These findings bear importance in taxonomic decisions about paraphyletic taxa and recognizing evolutionary and morphologically distinct lineages. 相似文献