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1.
A new species of Almeidea (Rutaceae) belonging to the neotropical tribe Galipeeae (subtribe Galipeinae) is described and illustrated. This new species, Almeidea albiflora, is known so far only from a few collections made in small disturbed forest remnants in the vicinity of Cachoeiro de Itapemirim, in the state of Espírito Santo, and by a single collection from northern Rio de Janeiro state, both in the domain of the Atlantic Forest, Eastern Brazil. Diagnostic features, like white petals, sericeous ovary and distal secondary axes as long as the proximal ones are identified. Pollen morphology is also described, and brief discussions of the relationships of the new taxon to other species of Almeidea, as well as comments on its conservation status, are provided.  相似文献   

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3.
Hyaloscyphaceae is the largest family in Helotiales, Leotiomycetes. It is mainly characterized by minute apothecia with well-differentiated hairs, but its taxonomic delimitation and infrafamilial classification remain ambiguous. This study performed molecular phylogenetic analyses using multiple genes including the ITS-5.8S rDNA, the D1–D2 region of large subunit of rDNA, RNA polymerase II subunit 2, and the mitochondrial small subunit. The primary objective was to evaluate the phylogenetic utility of morphological characters traditionally used in the taxonomy of Hyaloscyphaceae through reassessment of the monophyly of this family and its genera. The phylogenetic analyses inferred Hyaloscyphaceae as being a heterogeneous assemblage of a diverse group of fungi and not supported as monophyletic. Among the three tribes of Hyaloscyphaceae only Lachneae formed a monophyletic lineage. The presence of hairs is rejected as a synapomorphy, since morphologically diversified hairs have originated independently during the evolution of Helotiales. The true- and false-subiculum in Arachnopezizeae are hypothesized to have evolved through different evolutionary processes; the true-subiculum is likely the product of a single evolutionary origin, while the false-subiculum is hypothesized to have originated multiple times. Since Hyaloscyphaceae sensu lato was not resolved as monophyletic, Hyaloscyphaceae sensu stricto is redefined and only applied to the genus Hyaloscypha.  相似文献   

4.
Host-parasite coevolution is one of the main topics of the evolutionary biology of host-parasite associations. The majority of monogeneans parasitizing fish exhibit a high degree of host specificity. As a result, their evolutionary history might be intertwined with that of their fish hosts. The Cichlidae represent a diverse group of secondary freshwater fish with disjunctive distribution. Host-specific dactylogyrid monogeneans commonly parasitize cichlid fish. Their high diversity is associated with the main areas of cichlid distribution, i.e., Neotropical America and Africa. Nevertheless, the parasite fauna of cichlids from Neotropical America is still underexplored. A total of 31 cichlid species were examined for the presence of monogeneans, with 20 of them being parasitized. On these cichlids, 30 monogeneans belonging to the genera Gussevia, Trinidactylus, and Scadicleithrum were identified, 17 of them potentially representing new species for science. Phylogenetic analyses revealed three monophyletic groups of Neotropic cichlid monogeneans. Genus Gussevia was monophyletic, while Sciadicleithrum resulted polyphyletic. Sciedicleithrum from South America and Sciadicleithrum from Mexico represented two divergent lineages. The plesiomorphic Neotropical cichlid host group for dactylogyrid monogeneans was Cichlini, from which the representatives of other Neotropical cichlid tribes were colonised. Cophylogenetic analyses revealed a statistically significant cophylogenetic signal in the investigated host-parasite system, with host switch and duplication representing the main coevolutionary events for monogeneans parasitizing Neotropical cichlids. This scenario is in accordance with previous studies focussed on dactylogyridean monogeneans parasitizing freshwater fish in Europe and Africa.  相似文献   

5.
Abstract:A phylogenetic hypothesis based on nuclear ITS sequence data is presented for the familyPhysciaceae , based on various representatives of foliose and fruticose groups and a number of species selected from the crustose genera Rinodina and Buellia s.l. The analysis supports the monophyly of the Physcia - and theBuellia -groups. This is in agreement with existing morphological evidence, particularly ascus characters. ThePhyscia group in the analysis includes the genera Anaptychia, Heterodermia, Hyperphyscia,Mobergia , Phaeophyscia, Phaeorrhiza, Physcia, Physconia, Rinodina, andRinodinella , while the Buellia group includes Amandinea, Buellia and Diploicia. The genera Physcia, Phaeophyscia, Phaeorrhiza and Rinodinella were well supported as monophyletic groups. The support for Physconia is low. Rinodina and Buellia are not supported as monophyletic genera. In agreement with ascus and ascospore characters, Buellia lindingeri is placed within the Rinodina group, close to R. lecanorina. The genus Amandinea as currently circumscribed was not supported as a monophyletic group. The analysis confirms results from other lichen families that foliose members have evolved more than once from crustose lichens.Rinodina and Rinodinella species without chemical compounds in their thalli form the sister group toPhaeophyscia , and both groups form a monophyletic assemblage. A more detailed analysis of the Physcia group is presented. Whilst several of the foliose genera were well supported, there is only poor support for traditionally accepted crustose genera. The taxonomic implications of these findings are discussed.  相似文献   

6.
Advances in potter wasp systematics have been achieved recently, with classificatory changes resulting from analyses based upon large scale molecular datasets. For the Neotropics, recent hypotheses point to the occurrence of an exclusive clade recognized within the tribe Eumenini. In this group, several contributions regarding taxonomy and systematics have been proposed in the last five years, including the genus Alphamenes. This taxon contains seven described species whose distribution is exclusively Neotropical. Females are morphologically homogeneous, and characters related to copulatory organs are useful in male diagnosis. This contribution forms the first phylogenetic approach to include all species of Alphamenes, hence the first to strongly test for group monophyly. Our cladistic results recovered Alphamenes as a monophyletic group supported by male genital features. Relationships among included species also rely upon genitalic characters, highlighting the importance of these attributes for eumenine systematics. Recent phylogenetic investigations applied to the Neotropical fauna of potter wasps represent desirable advancements towards a natural classification for the group.  相似文献   

7.
基于线粒体CO Ⅰ基因的闪蛱蝶亚科系统发育关系研究   总被引:1,自引:0,他引:1  
测定了重要林业害虫闪蛱蝶亚科Apaturinae 11属17种蝶类的线粒体细胞色素氧化酶Ⅰ的部分序列,并结合由GenBank下载的该亚科4种蝶类的相应序列进行分析,探讨了闪蛱蝶亚科各属间的系统发育关系。以玉杵带蛱蝶Athymajina,白斑眼蝶Penthema adelma,忘忧尾蛱蝶Polyura nepenthes和白带螯蛱蝶Charaxes bernardus作为外群,采用PAUP4.0b4a软件构建了闪蛱蝶亚科的MP和NJ分子系统树。虽然COI基因数据中第3位点的转换替换已达饱和,但由于这些位点含有大量系统发育信息,因而在数据统计分析时并没有将这些位点删除。同时通过对各分枝稳定性的比较,研究在简约分析中不同转换/颠换加权方式对假定所有特征具有相同权重的影响。分子系统树显示:NJ和不同转换/颠换加权方式下构建的MP系统树中闪蛱蝶亚科均有4个主要的聚类簇,该亚科系统树中存在许多置信度高且稳定的分枝,同时也存在一些因分枝置信度低且不稳定而使其分类地位不能确定的类群。在所构建的系统树中,由分子数据得到的蛱蝶亚科系统发育关系与传统分类学的基本一致,其中迷蛱蝶属Mimathyma为单系群;累积蛱蝶Lelecella limenitoides为明窗蛱蝶Dilipa fenestra的姐妹群且支持二者关系的置信度很高;支持将白斑迷蛱蝶Mimathyma schrenckii,迷蛱蝶M.chevana,夜迷蛱蝶M.nycteis,栗铠蛱蝶Chitoria subcaerulea,黄带铠蛱蝶C.fasciola,铂铠蛱蝶C.pallas,and银白蛱蝶Helcyra subalba等物种由闪蛱蝶属中移出的修订。  相似文献   

8.
Understanding species evolution and improvement requires information of their genome origin and differentiation. Among the species in the family Gramineae, genome identities of Agropyron-Elytrigia-Leymus group are still ambiguous. In order to delineate the genome relationship, nucleotide sequence analysis in the rDNA ITS regions was carried out among the species in the genera Elytrigia, Agropyron, Psathyrostachys, Leymus, and Psacopyrum containing E, St, P, Ns, and Xm genomes. The ITS-1 and ITS-2 showed a narrow range of variation in length except for the presence of a pentanucleotide, TGGGG, in/del in some haplotypes, whereas higher numbers of nucleotide substitutions were observed in most genera. There were 187 variable sites in the ITS-1, 5.8S, and ITS-2 regions, in which a few genome specific mutations were observed. While the level of variation was similar between ITS-1 and ITS-2, the rate of transition mutation versus transversion mutations was different among the ITS-1, 5.8S, and ITS-2 segments. GC contents of the ITS regions ranged between 55–65% between genomes and the haplotypes of P and H genomes were slightly higher than others. In phylogenetic analysis, the ITS haplotypes were classified into two groups; one containing H, Ns, NsXm genomes, and another containing P, St, and E genomes, which are congruous to the genome affinities from other studies. Among the four genomes in Pascopyrum smithii (2n=8x=56, StStNsNsHHXmXm), the haplotypes of H and St genomes were identified with the reference diploid species, but the haplotypes having Ns and Xm genomes were not found in the present analysis.  相似文献   

9.
Pollen analysis and parsimony-based phylogenetic analyses of the genera Cistus and Halimium, two Mediterranean shrubs typical of Mediterranean vegetation, were undertaken, on the basis of cpDNA sequence data from the trnL-trnF, and trnS-trnG regions, to evaluate limits between the genera. Neither of the two genera examined formed a monophyletic group. Several monophyletic clades were recognized for the ingroup. (1) The ??white and whitish pink Cistus??, where most of the Cistus sections were present, with very diverse pollen ornamentations ranging from striato-reticulate to largely reticulate, sometimes with supratectal elements; (2) The ??purple pink Cistus?? clade grouping all the species with purple pink flowers belonging to the Macrostylia and Cistus sections, with rugulate or microreticulate pollen. Within this clade, the pink-flowered endemic Canarian species formed a monophyletic group, but with weak support. (3) Three Halimium clades were recovered, each with 100% bootstrap support; all Halimium species had striato-reticulate pollen. Two Halimium clades were characterized by yellow flowers, and the other by white flowers.  相似文献   

10.
Helopini is a diverse tribe in the subfamily Tenebrioninae with a worldwide distribution. The New World helopine species have not been reviewed recently and several doubts emerge regarding their generic assignment as well as the naturalness of the tribe and subordinate taxa. To assess these questions, a preliminary cladistic analysis was conducted with emphasis on sampling the genera distributed in the New World, but including representatives from other regions. The parsimony analysis includes 30 ingroup species from America, Europe and Asia of the subtribes Helopina and Cylindrinotina, plus three outgroups, and 67 morphological characters. Construction of the matrix resulted in the discovery of morphological character states not previously reported for the tribe, particularly from the genitalia of New World species. A consensus of the 12 most parsimonious trees supports the monophyly of the tribe based on a unique combination of characters, including one synapomorphy. None of the subtribes or the genera of the New World represented by more than one species (Helops Fabricius, Nautes Pascoe and Tarpela Bates) were recovered as monophyletic. Helopina was recovered as paraphyletic in relation to Cylindrinotina. One Nearctic species of Helops and one Palearctic species of Tarpela (subtribe Helopina) were more closely related to species of Cylindrinotina. A relatively derived clade, mainly composed by Neotropical species, was found; it includes seven species of Tarpela, seven species of Nautes, and three species of Helops, two Nearctic and one Neotropical. Our results reveal the need to deeply re-evaluate the current classification of the tribe and subordinated taxa, but a broader taxon sampling and further character exploration is needed in order to fully recognize monophyletic groups at different taxonomic levels (from subtribes to genera).  相似文献   

11.
Based on a considerably enlarged sampling, a phylogenetic analysis of the largest group of didymocarpoid Gesneriaceae, the ??advanced Asiatic and Malesian genera??, was performed, covering all but 3 of the 60 genera presently recognised in this group (20 of these, mostly from China, are monotypic). The results suggest that no fewer than 17 out of the 57 genera examined are poly- (or rarely para-)phyletic. Highly polyphyletic are Briggsia, Chirita, Henckelia and Raphiocarpus. Only a dozen of the non-monotypic genera (including the three species-richest genera, Cyrtandra, Aeschynanthus and Agalmyla) are confirmed as monophyletic entities, though some exhibit considerable genetic variation. For eight genera, no statement can be made, as only one (of two or several) species was included in the analysis. For a dozen of the (particularly Chinese) monotypic genera a close relationship (or possible congenerity) with other genera was found. In China, only Allostigma, Cathayanthe, Conandron and Metapetrocosmea seem to have no strong affinities to other genera, indicating that they represent phylogenetically isolated lineages or represent remnants of previously larger and earlier diversified groups. The present study forms the foundation for targeted molecular, morphological and phytogeographic studies of the polyphyletic and monotypic genera and particular of clades of genera with interrelations uncovered here for the first time.  相似文献   

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The Sino-Himalayan Mountain Region is a major center of diversity of Heracleum (Apiaceae, Tordylieae, Tordyliinae), yet the phylogenetic relationships among its rich diversity of endemic taxa are largely unknown. In this study, we (1) investigate the monophyly of Heracleum and ascertain the phylogenetic placements of those species of Heracleum from China that fall outside of the group; (2) estimate phylogenetic relationships within Heracleum sensu stricto, particularly among those species occurring in the Hengduan Mountain Region of southwestern China; and (3) reconstruct the biogeographic history of Heracleum sensu stricto. To achieve these objectives, Bayesian inference and maximum-parsimony analyses of the nuclear ribosomal DNA (nrDNA) internal transcribed spacer (ITS) region and five noncoding chloroplast DNA (cpDNA) loci (rps16-trnK, rps16 intron, trnQ-rps16, rpl32-trnL, and psbA-trnH), separately and in combination, were carried out. Fruit morphology of the Chinese Heracleum species was examined. Statistical dispersal-vicariance analysis (S-DIVA) was used to reconstruct the biogeographic history. In total, 114 accessions were considered, which included 88 species representing eight genera of subtribe Tordyliinae, 28 of the 29 species of Heracleum occurring in China, and 4 species of Angelica as outgroups. The genus Heracleum is monophyletic upon the exclusion of nine species of Heracleum from China and the inclusion of the Caucasian monotypic genera Mandenovia and Symphyoloma. These nine excluded species show affinities to Tetrataenium, Semenovia, and Angelica. The species of Heracleum endemic to southwestern China form a moderately to strongly supported clade; however, major discordance between the ITS- and cpDNA-derived phylogenies, lack of resolution in the trees, and polyphyly of several species preclude unequivocal hypotheses of phylogenetic relationship. The distinctly clavate vittae, shorter than the length of the mericarp, is a diagnostic feature for Heracleum sensu stricto. Heracleum originated in the West Palearctic, with three possible migration routes leading to its present-day distribution. Major topological conflicts between the ITS and cpDNA trees may be due to interspecific hybridization and/or incomplete lineage sorting. The taxonomic limits of many Chinese Heracleum species remain unclear, possibly because of recent radiation in the Hengduan Mountains.  相似文献   

14.
Inferring the evolutionary and biogeographic history of taxa occurring in a particular region is one way to determine the processes by which the biodiversity of that region originated. Tree boas of the genus Corallus are an ancient clade and occur throughout Central and South America and the Lesser Antilles, making it an excellent group for investigating Neotropical biogeography. Using sequenced portions of two mitochondrial and three nuclear loci for individuals of all recognized species of Corallus, we infer phylogenetic relationships, present the first molecular analysis of the phylogenetic placement of the enigmatic C. cropanii, develop a time-calibrated phylogeny, and explore the biogeographic history of the genus. We found that Corallus diversified within mainland South America, via over-water dispersals to the Lesser Antilles and Central America, and via the traditionally recognized Panamanian land bridge. Divergence time estimates reject the South American Caribbean-Track as a general biogeographic model for Corallus and implicate a role for events during the Oligocene and Miocene in diversification such as marine incursions and the uplift of the Andes. Our findings also suggest that recognition of the island endemic species, C. grenadensis and C. cookii, is questionable as they are nested within the widely distributed species, C. hortulanus. Our results highlight the importance of using widespread taxa when forming and testing biogeographic hypotheses in complex regions and further illustrate the difficulty of forming broadly applicable hypotheses regarding patterns of diversification in the Neotropical region.  相似文献   

15.
The length polymorphism of ribosomal DNA ITS-1 intergenic spacer was analyzed in eight species of triatomines belonging to Triatoma, Rhodnius, and Panstrongylus genera. The analyzed species were Rhodnius domesticus, R. neivai, R. robustus, Triatoma brasiliensis, T. infestans, T. vitticeps, Panstrongylus megistus, and P. herreri. These insects are vectors of Chagas' disease, one of the most prominent public health problems among South American countries. This work allowed the differentiation between species of the Triatomini and Rhodniini tribes through the analysis of ITS-1 length polymorphism by PCR and RFLP techniques. The species of the Triatoma and Panstrongylus genera presented an amplified ITS-1 fragment between 600 and 1000 bp, whereas Rhodnius presented a less variable ITS-1 length fragment, around 300 bp, which could reflect the monophyletic origin of the Rhodniini tribe. Species belonging to this genus were further differentiated by RFLP with HaeIII and AluI endonucleases. Our results corroborate the hypothesis of polyphyletic origin in this group of insects and contribute to knowledge about evolutionary relationships in triatomines.  相似文献   

16.
Karyotypes in the worldwide subfamily Oecanthinae show variations in diploid number, chromosome morphology, and sex-chromosome system. This study described the chromosome set and phylogenetic relationships of four Neotropical species, Oecanthus lineolatus, O. valensis, O. pallidus, and O. pictus. We used classical cytogenetics and Bayesian Inference for phylogenetic reconstruction, using the mitochondrial genes COI, 12S rRNA, and 16S rRNA; and analyzed the phylogenetic patterns of changes in chromosome numbers, using ChromEvol. We observed differences in chromosome number among species and two different sex-chromosome systems. Oecanthus pictus showed 2n = 21, X0♂/22, XX♀; O. lineolatus, 2n = 20, XY♂/XX♀; and O. valensis and O. pallidus, 2n = 18, XY♂/XX♀. The karyotype of Oecanthus was asymmetric, one group with large chromosomes and variation in heterochromatin distribution, and another with small acrocentric chromosomes. The phylogenetic tree recovered two main groups: one with the Palearctic species and another with species from different bioregions, but with low posterior probability. The Neotropical species grouped separately, O. valensis and O. pictus with Nearctic and Ethiopian species, and O. pallidus and O. lineolatus in another, well-supported clade. Together, the phylogenic and chromosome data suggest descending dysploidy events during the evolution of the group. Keywords: Insect, karyotype, Chromosome, Bayesian Inference, Oecanthinae  相似文献   

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During a survey fungal diversity of xylariaceous fungi in Thailand, a new Nemania species, N. plumbea, was identified. Nemania plumbea is characterized by soft-textured grey stromata on a persistent mat of white hyphae, pale brown ascospores with a short germ-slit on the more convex side. It also produces a Geniculosporium-like anamorph in culture. In order to evaluate its phylogenetic relationships among related species and genera, ITS-5.8S rDNA and RPB2 were analysed separately and simultaneously. Results from the phylogenetic analyses indicate that there is close phylogenetic association between N. plumbea and N. aenea. A preliminary account into the natural grouping of Xylariaceae based on ITS-5.8S rDNA and RPB2 sequences is also discussed.  相似文献   

19.
We analyzed nuclear ITS sequences of 95 samples representing 85 taxa of Cyperus sensu lato under maximum likelihood and Bayesian frameworks. This work is exploratory in nature with the objectives of gaining insight into relationships among New World Cyperus and targeting problematic clades for future research. In our resulting phylogenetic hypothesis, the genera Cyperus, Kyllinga, Oxycaryum, Pycreus, and Queenslandiella were intermixed, confirming the paraphyletic nature of Cyperus as reported by other researchers. We recovered a strongly-supported clade whose members possess C4 photosynthesis. The C3/C4 split has also been previously reported based on research employing different methods of phylogenetic estimation and different molecular markers. We provide preliminary evidence that Cyperus sections Haspani, Laxiglumi, Strigosi, Thunbergiani, and Umbellati are not monophyletic. Cyperus subgenus Diclidium, which is characterized by a unique mode of spikelet shattering, is monophyletic and highly derived in our analysis, but additional taxa are needed for a more robust assessment. We discuss hypothesized relationships and taxonomic implications for several other species and species complexes.  相似文献   

20.
We present a phylogenetic investigation of the Northern Clade, the major monophyletic clade within the freshwater fish family Cobitidae, one of the most prominent families of freshwater fishes found in Asian and European waters. Phylogenetic reconstructions based on the cytochrome b and RAG-1 genes show the genera Microcobitis, Sabanejewia, Koreocobitis and Kichulchoia as monophyletic groups. These reconstructions also show a Cobitis sensu lato and a Misgurnus sensu lato group. The Cobitis sensu lato group includes all species of Cobitis, Iksookimia, Niwaella and Kichulchoia, while the Misgurnus sensu lato group includes Misgurnus, Paramisgurnus and Koreocobitis. Although the monophyly of both the Cobitis sensu lato and Misgurnus sensu lato groups is supported, relationships within the groups are incongruent with current generic definitions. The absence of monophyly of most genera included in the Cobitis sensu lato group (Cobitis, Iksookimia and Niwaella) or their low genetic differentiation (Kichuchoia) supports their consideration as synonyms of Cobitis. Molecular phylogenies indicate that the Asian species of Misgurnus experienced a mitochondrial introgression from a lineage of Cobitis. We also find two nuclear haplotypes in the same Cobitis species from the Adriatic area that, in the absence of morphological differentiation, may indicate molecular introgression. Most lineages within the Northern Clade consist of species found in East Asia. However, some lineages also contain species from Europe and Asia Minor. The phylogenetic relationships presented here are consistent with previous studies suggesting an East Asian origin of the Northern Clade. According to the current distributions and phylogenetic relationships of the Misgurnus sensu lato and Cobitis clade lineages, particularly of M. fossilis and C. melanoleuca, the range expansion of East Asian species into Europe was most likely via Siberia into Northern and Central Europe. Phylogenetic analyses also show that the Cobitis sensu lato group consists of two clear subgroups (I and II), each presenting geographical differences. Subgroup I is distributed exclusively in East Asian drainages with an Eastern European offshoot (C. melanoleuca), whereas Subgroup II includes species widespread throughout Europe (including the Mediterranean), Asia Minor, the Black Sea and the Caucasus, with some lineages related to species restricted to East Asia.  相似文献   

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