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1.
The phylogenetic relationships within many clades of the Crassulaceae are still uncertain, therefore in this study attention was focused on the “Acre clade”, a group comprised of approximately 526 species in eight genera that include many Asian and Mediterranean species of Sedum and the majority of the American genera (Echeveria, Graptopetalum, Lenophyllum, Pachyphytum, Villadia, and Thompsonella). Parsimony and Bayesian analyses were conducted with 133 species based on nuclear (ETS, ITS) and chloroplast DNA regions (rpS16, matK). Our analyses retrieved four major clades within the Acre clade. Two of these were in a grade and corresponded to Asian species of Sedum, the rest corresponded to a European–Macaronesian group and to an American group. The American group included all taxa that were formerly placed in the Echeverioideae and the majority of the American Sedoideae. Our analyses support the monophyly of three genera – Lenophyllum, Thompsonella, and Pachyphytum; however, the relationships among Echeveria, Sedum and the various segregates of Sedum are largely unresolved. Our analyses represents the first broad phylogenetic framework for Acre clade, but further studies are necessary on the groups poorly represented here, such as the European and Asian species of Sedum and the Central and South American species of Echeveria.  相似文献   

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3.
The babblers (Timaliidae) form a large songbird family, which achieves its highest diversity in South-East Asia. As part of an ongoing phylogenetic investigation of this group, we focus here on the systematic position of two Asian genera, Yuhina and Stachyris , using cytochrome b , 16S and 12S sequence data. The analysis suggests that the two genera, as defined by morphological characters, are not monophyletic. The white-bellied yuhina Yuhina zantholeuca , which has been placed among the typical yuhinas by most authors, is not a babbler. The other yuhinas studied, six continental species and a species endemic to Taiwan, form a clade that includes also three species of Stachyris endemic to the Philippines. The other Stachyris are not related to this clade, and can be divided into two groups that correspond to morphological and geographical differences among the species.  相似文献   

4.
Leveillula on monocotyledonous plants have been recorded as L. taurica by several authors, whereas the fungus on Allium has been described as an independent species, namely L. allii, by some authors. We sequenced ca 600 bp of the rDNA ITS region for two Leveillula specimens from Allium and Polianthes (both from monocotyledons) and compared them with several already published sequences from Leveillula isolates from dicotyledons. Pair-wise percentages of sequence divergences were calculated for all Leveillula isolates. The ITS sequence of the Polianthes isolate was identical to L. taurica on Helianthus and Vicia. The sequence of the Allium isolate was 99.5 % identical to L. taurica on Euphorbia, Haplophylum, Peganum, etc. These results suggest close relationships between monocot and dicot pathogenic Leveillula species. The identity between two monocot isolates was 98.4 %. Phylogenetic analysis revealed that the two monocot isolates do not group into a clade together. This result suggests that Leveillula acquired parasitism to monocots at least twice independently.  相似文献   

5.
Phylogenetic relationships, limits of species, and genera within Lycoperdaceae, were inferred by use of ITS and LSU nu-rDNA sequence data. Lycoperdaceae was confirmed as monophyletic, and Mycenastrum corium as a sister taxon to the ingroup. Four major clades were identified and received weak to moderate support and correspond with the genera Lycoperdon, Bovista, Calvatia, and Disciseda. The Lycoperdon clade includes species from Lycoperdon, Vascellum, Morganella, Handkea, Bovistella, and Calvatia. The structure within the Lycoperdon clade is unresolved and several clades are more or less unsupported, which suggests treating the supported Lycoperdon clade as the genus Lycoperdon. L. nigrescens and L. caudatum occur on single branches and their phylogenetic positions could not be resolved. The phylogenetic analyses identified 31 species of Lycoperdon, 11 species of Bovista, six species of Calvatia, and two species of Disciseda. In Lycoperdon three new species were recognized. A new species closely related to B. limosa is identified and discussed. A classification of Lycoperdaceae is proposed based on the results of the phylogenetic analyses. Morphological characters of species within and among identified clades are discussed.  相似文献   

6.
Phylogenetic relationships are complex within the Lithospermeae, a large subgroup of the Boraginaceae s.str. The relationships of New World Lasiarrhenum, Macromeria, Nomosa, Onosmodium, Perittostoma, and Psilolaemus to subcosmopolitan and much larger Lithospermum have not been critically investigated in the recent past. No molecular data on the phylogeny of these genera and Lithospermum have so far been published. We investigated the relationships within Lithospermeae using three loci (nuclear ITS plus 5.8S rRNA, chloroplast trnL-F-spacer, and trnS-G-spacer) and micromorphological character traits (pollen, nutlets). Lithospermum s.l. constitutes the sistergroup of Asian Ulugbekia and is monophyletic only when its American segregates “Macromeria”, monotypic Nomosa, and Onosmodium are included. Both the African and the South American species groups of Lithospermum are monophyletic, but North American representatives are not resolved in a single clade. Morphological characters that have been considered as important for generic delimitation in the past (such as large, yellow corollas without faucal scales, particular pollen types, coarsely veined leaves, shrubby habit) have evolved in at least two only distantly related lineages within Lithospermum s.l. The reduction of American “Macromeria”, Nomosa, and Onosmodium as well as Asian Ulugbekia under Lithospermum is proposed to render the latter monophyletic. This redefined Lithospermum s.l. appears to have undergone a type of recent “island radiation” in the Americas, reflected in a morphological diversity far exceeding that found in the Old World.  相似文献   

7.
A molecular phylogeny of Hebeloma species from Europe   总被引:2,自引:1,他引:1  
In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.  相似文献   

8.
A phylogeny of the lichen family Porinaceae using mitochondrial SSU rDNA sequences is presented, with special focus on foliicolous taxa. Fifty specimens of 28 mostly tropical species, representing eight species groups of Porina as well as the genus Trichothelium, were analysed together with species of other members of Ostropomycetidae, and using Agyriaceae as outgroup. We performed the phylogenetic analyses with a Bayesian approach and under the criterion of maximum parsimony. Four main clades can be distinguished: the P. nitidula-group s. lat. (including Trichothelium, P. papillifera and P. rubescens), the Porina epiphylla-group s. lat. (including the P. radiata-, the P. nucula-, the P. imitatrix- and the P. epiphylla-group s. str.) and two clades of the P. rufula-group. The genus Porina as understood by all recent concepts is paraphyletic, and Trichothelium is nested within the Porina nitidula-group. The non-setose P. repanda forms a monophyletic clade with Trichothelium. The tree does not support a monophyletic origin of substrate preferences or photobiont selection. Species-specific associations with morphologically different trentepohlioid photobionts mapped on the tree suggest that closely related mycobiont species switch between different types of algae.  相似文献   

9.
An earthworm biodiversity survey of the Philippines has yielded 14 new species of the perichaetine megascolecid genus Pleionogaster, previously known from only a few species from scattered Philippine locations. Bicol, the southern peninsula of Luzon, has intact forests on several isolated volcanic peaks and other remote areas. Collections made in these forests yielded the following new species, here presented by type location: Mt. Malinao, Pleionogaster albayensis, P. bicolensis, P. castilloi, P. malinaoensis, P. tiwiensis; Mt. Isarog, P. ffitchae, P. isarogensis; Mt. Bulusan, P. bulusanensis, P. hongi, P. sorsogonensis; Catanduanes Island, P. nautsae, P. viracensis; Caramoan Peninsula, P. caramoanensis, P. nillosae. Most of the species were found only in the neighborhood of the type locality, but P. bicolensis occurs in two locations in northern Bicol. Intraspecific variation in P. castilloi was observed between northern and southern flanks of Mt. Malinao. The importance of several previously overlooked Pleionogaster traits is demonstrated by their homogeneity within species reported here.Full article published online at http://www.senckenberg.de/odes/06-08.htm.  相似文献   

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11.
Phylogenetic relationships among chain-forming Cochlodinium species, including the harmful red tide forming dinoflagellate Cochlodinium polykrikoides, were investigated using specimens collected from coastal waters of Canada, Hong Kong, Japan, Korea, Malaysia, México, Philippines, Puerto Rico, and USA. The phylogenetic tree inferred from partial (D1–D6 regions) large subunit ribosomal RNA gene (LSU rDNA) sequences clearly differentiated between C. polykrikoides and a recently described species, Cochlodinium fulvescens. Two samples collected from the Pacific coasts of North America (British Columbia, Canada and California, USA) having typical morphological characters of C. fulvescens such as the sulcus located in the intermediate region of the cingulum, were closely related to C. fulvescens from western Japan in the phylogenetic tree. Cochlodinium polykrikoides formed a monophyletic group positioned as a sister group of the C. fulvescens clade with three well-supported sub-clades. These three clades were composed of (1) East Asian, including specimens collected from Hong Kong, western Japan, and southern Korea, (2) Philippines, from Manila Bay, Philippines and Omura Bay, Japan, and (3) American/Malaysian, from the Atlantic coasts of USA, the Pacific coast of México, Puerto Rico, and Borneo Island, Malaysia. Each of these clades is considered to be a so-called “ribotype” representing the population inhabiting each region, which is distinguished based on ribosomal RNA gene sequences in the species despite similarities in their morphological characters.  相似文献   

12.
The “Vibrio fischeri species group” recently was reclassified as a new genus, Aliivibrio, comprising four species, Aliivibrio fischeri, Aliivibrio logei, Aliivibrio salmonicida, and Aliivibrio wodanis. Only limited phylogenetic analysis of strains within Aliivibrio has been carried out, however, and taxonomic ambiguity is evident within this group, especially for phenotypically unusual strains and certain strains isolated from bioluminescent symbioses. Therefore, to examine in depth the evolutionary relationships within Aliivibrio and redefine the host affiliations of symbiotic species, we examined several previously identified and newly isolated strains using phylogenetic analysis based on multiple independent loci, gapA, gyrB, pyrH, recA, rpoA, the luxABE region, and the 16S rRNA gene. The analysis resolved Aliivibrio as distinct from Vibrio, Photobacterium, and other genera of Vibrionaceae, and resolved A. fischeri, A. salmonicida, A. logei, and A. wodanis as distinct, well-supported clades. However, it also revealed that several previously reported strains are incorrectly identified and that substantial unrecognized diversity exists in this genus. Specifically, strain ATCC 33715 (Y-1) and several other strains having a yellow-shifted luminescence were not members of A. fischeri. Furthermore, no strain previously identified as A. logei grouped with the type strain (ATCC 29985T), and no bona-fide strain of A. logei was identified as a bioluminescent symbiont. Several additional strains identified previously as A. logei group instead with the type strain of A. wodanis (ATCC BAA-104T), or are members of a new clade. Two strongly supported clades were evident within A. fischeri, a phylogenetic structure that might reflect differences in the host species or differences in the ecological incidence of strains. The results of this study highlight the importance of basing taxonomic conclusions on examination of type strains.  相似文献   

13.
WUSCHEL相关-同源盒(WUSCHEL related-homeobox, WOX)基因家族是一类植物特有的转录因子基因家族,在植物的生长发育过程中发挥重要作用。本研究利用芥菜(Brassica juncea)基因组数据,通过HUMMER、Smart等软件进行检索筛选,共鉴定出51个WOX基因家族成员。利用Expasy在线软件对这些家族成员的蛋白质分子量、氨基酸序列长度、等电点等进行分析,并利用生物信息学软件对芥菜WOX基因家族进化关系、保守区域、基因结构等进行系统性分析,将芥菜WOX基因家族分为古老支、中间支和WUS支/现代支3个亚家族。结构分析表明,同一亚家族内的WOX转录因子家族成员的保守结构域的种类、组织形式以及基因结构具有高度的一致性,而不同亚家族之间呈现一定的多样性。51个WOX基因不均匀分布于芥菜18条染色体上,这些基因的启动子大多含有响应光、激素和非生物逆境胁迫相关的顺式作用元件。利用转录组数据和实时荧光定量PCR (real-time fluorescence quantitative PCR, qRT-PCR)分析发现,芥菜WOX基因的表达具有时空特异性,其中B...  相似文献   

14.
The hypothesis that similar conidial morphologies in aquatic hyphomycetes are a result of convergent evolution was tested using molecular sequence data. Cladistic analyses were performed on partial sequences of 28S rDNA of seven species of Lemonniera, one species of Margaritispora and one species of Goniopila. Lemonniera has tetraradiate conidia with long arms, whereas Margaritispora and Goniopila have typically globose (isodiametric) conidia, with short conical protuberances in a stellate or quadrangular arrangement. Lemonniera and Margaritispora have phialidic conidiogenesis and both produce dark, minute sclerotia in culture whereas Goniopila has holoblastic conidiogenesis and does not produce sclerotia in culture. Goniopila produces a microconidial phialidic synanamorph in culture. All three genera have schizolytic conidial secession. Molecular analyses demonstrate that Lemonniera species are placed in two distinct clades: one within Leotiomycetes; the other within Pleosporales, Dothideomycetes. Margaritispora is placed with Lemonniera species within Leotiomycetes. Goniopila and Lemonniera pseudofloscula are placed within Dothideomycetes. No morphological character was entirely congruent with the molecular derived phylogeny. This suggests that for the group of species studied, conidial shape is not a reliable indicator of phylogeny but more likely the result of convergent evolution in response to the aquatic environment.  相似文献   

15.
16.
Seven new calochroid and fulvoid species of Cortinarius   总被引:1,自引:0,他引:1  
We describe seven new European species of Cortinarius. All species are based on analyses of morphological and DNA sequence data. They all belong to a well-supported clade comprising most species traditionally treated in Cortinarius subgenus Phlegmacium sections Fulvi and Calochroi (i.e. the/Calochroi clade). All taxa are either fulvoid (containing anthraquinoid pigments) or calochroid (without these pigments). Morphological and ecological data are presented for all species and compared with similar species. A dichotomous key is presented for C. calochrous and similar species, including all six newly described calochroid species. The calochroid species C. albertii, C. chailluzii, C. cisticola, C. sancti-felicis, C. selandicus and C. vesterholtii spp. nov., and the fulvoid species C. langeorum sp. nov. are described.  相似文献   

17.
The monospecific genus Rhodoplagiochila, previously known only from the type collected in the Venezuelan Andes, has been collected at a second site close to the type locality. Up to now, generic status of Rhodoplagiochila has been accepted by most authors, but the taxon had been alternately assigned to Plagiochilaceae or Lophoziaceae. Phylogenetic analyses of nrITS sequences from Rhodoplagiochila and other representatives of the Plagiochilaceae clearly reveal the former to be in a clade with members of the Neotropical–Atlantic European Plagiochila sect. Arrectae. Within the Arrectae, Rhodoplagiochila is positioned in a robust clade made up of several accessions of Plagiochila bifaria. Morphologically, Rhodoplagiochila differs from other phenotypes of P. bifaria by the papillose leaf surface and a leaf margin which is ciliately toothed all-around. As an outcome of the molecular and morphological investigations, Rhodoplagiochila rosea is treated as a variety of P. bifaria, and the new combination P. bifaria var. rosea comb. et stat. nov. is proposed. In tropical America the family Plagiochilaceae seems to be represented only by Plagiochila.  相似文献   

18.
滇白珠是我国重要的民族药用植物,广泛分布于长江以南地区,是一个分类困难的复合群。为了探讨其种下分类关系,该文对滇白珠复合群(包括毛滇白珠、秃果白珠和滇白珠3个变种)进行网罗式采样,基本覆盖了该复合群在中国的分布范围,同时包括菲律宾和马来西亚的各1个居群,共计81个居群241个个体,通过联合两个变异位点适中的叶绿体片段rpl33-psa J和trn L-rpl32,构建基于最大似然法(Maximum Likelihood)和贝叶斯法(Bayesian Inference)的系统发育树,以及Neighbor-Net法构建系统发育网络。结果表明:滇白珠复合群内具有明显的遗传差异,这种差异性相比形态,与地域分布相关性更大。系统发育分析显示,滇白珠复合群分为3个支系。其中:一支包括中国台湾和菲律宾南达沃的居群,为变种秃果白珠,符合前人分类结果;一支包括分布于横断山脉区域的居群,由变种毛滇白珠和滇白珠组成;剩余一支包括分布于华东南区域的居群,同样由变种毛滇白珠和滇白珠组成。分子证据支持基于形态分类的秃果白珠作为变种,而不支持毛滇白珠作为变种的处理。这样的遗传分化式样可能是由地理隔离导致,这一结果为民族药滇白珠的种质资源评价和保护利用奠定了分类学框架。然而,变种滇白珠居群间的谱系发生关系却尚未得到很好地解决,特别是无法明晰华东南大部分居群间的遗传分化格局,需要进一步补充样本通过谱系地理学手段,并寻找分辨率更高的核基因分子标记进行更深入的研究。  相似文献   

19.
A new species, Hypocrella panamensis, is described from collections and cultures obtained on Barro Colorado Island, Panama. In order to aid in placement of this fungus, phylogenetic analyses were conducted using LSU (rDNA) sequences. Hypocrella panamensis is characterized by possessing pulvinate stromata with a Lecanicillium-like anamorphic state and superficial perithecia. Hypocrella panamensis consistently grouped in a clade containing Hypocrella nectrioides, H. phyllogena, and H. africana (100 % PP). Most species of Hypocrella possess Aschersonia or Hirsutella anamorphs. Hypocrella panamensis is unique in the genus Hypocrella in possession of a Lecanicillium-like anamorphic state. In its biological habit Hypocrella panamensis is similar to other species in Hypocrella in that it infects and degrades the scale insect, then grows superficially on nutrients that emerge to the plant surface through the stylet wound.  相似文献   

20.
The pathogen Chrysoporthe cubensis (formerly Cryphonectria cubensis) is best known for the important canker disease that it causes on Eucalyptus species. This fungus is also a pathogen of Syzygium aromaticum (clove), which is native to Indonesia, and like Eucalyptus, is a member of Myrtaceae. Furthermore, C. cubensis has been found on Miconia spp. native to South America and residing in Melastomataceae. Recent surveys have yielded C. cubensis isolates from new hosts, characterized in this study based on DNA sequences for the ITS and β-tubulin gene regions. These hosts include native Clidemia sericea and Rhynchanthera mexicana (Melastomataceae) in Mexico, and non-native Lagerstroemia indica (Pride of India, Lythraceae) in Cuba. Isolates from these hosts and areas group in the sub-clade of C. cubensis accommodating the South American collections of the fungus. This sub-clade also includes isolates recently collected from Eucalyptus in Cuba, which are used to epitypify C. cubensis. New host records from Southeast Asia include exotic Tibouchina urvilleana from Singapore and Thailand and native Melastoma malabathricum (Melastomataceae) in Sumatra, Indonesia. Consistent with their areas of occurrence isolates from the latter collections group in the Asian sub-clade of C. cubensis. DNA sequence comparisons of isolates from Tibouchina lepidota in Colombia revealed that they represent a new sub-clade within the greater Chrysoporthe clade. Isolates in this clade are described as Chrysoporthe inopina sp. nov., based on distinctive morphological differences.  相似文献   

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