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1.
Parsimony analyses of SSU rDNA sequences were conducted to examine phylogenetic relationships of selected genera within the families Cladoniaceae, Stereocaulaceae, Icmadophilaceae and Baeomycetaceae (lichen-forming ascomycetes). The analyses included 93 taxa (84 species) representing various groups of ascomycetous fungi. Analyses of the matrix with pre-aligned sequences were performed using heuristic and parsimony ratchet searches, and support values for the same matrix were calculated using parsimony jackknifing. The results support the recognition of the four families. Cladoniaceae are recircumscribed to accommodate Cladia, Cladonia, Heterodea, Metus, Pilophorus, Pycnothelia, Ramalea, Thysanothecium and the newly erected genus Carassea. Myelorrhiza is excluded from the family, while the status of other potential members, Calathaspis, Gymnoderma s.str. and Squamella, remains unresolved. Baeomycetaceae include Baeomyces and Phyllobaeis. Stereocaulaceae include Stereocaulon only, although the status of Muhria is still unclear. Finally, Icmadophilaceae include Dibaeis, Endocena, Knightiella, Icmadophila, Siphula and Thamnolia, while the status of Pseudobaeomyces and Siphulella requires further elucidation. The genus Cladonia appeared to be a polyphyletic assemblage, and accordingly, a new genus Carassea S. Stenroos, gen. nov., represented by C. connexa (Vain.) S. Stenroos, comb. nov., is described. Carassea is most closely related to Pycnothelia and Metus in the Cladoniaceae. Siphula, represented in the present analysis by six species, is not monophyletic, and is in need of reclassification.  相似文献   

2.
A cladistic analysis of 44 species of the generaCladina andCladonia is presented.Pycnothelia papillaria, Cladia aggregata andC. retipora were used as outgroup taxa. The consensus of all equally parsimonious trees suggests a common ancestral origin for species inCladonia andCladina while the generaPycnothelia andCladia cluster outside this group. The results do not support distinction ofCladina at genus level although it is distinguished as a monophyletic group but within the genusCladonia. The current sectional division ofCladonia is not supported. SectionsCocciferae andHelopodium are best supported but even these groups as currently delimited seem to in include elements that are more closely related to species of the other sections, e.g.C. carneola of sect.Cocciferae andC. pityrophylla of sect.Helopodium. Sections such asUnciales andPerviae seem to be artificial assemblages. In general the evolutionary scheme of the genus seems to be more complicated than revealed by the current sectional division.  相似文献   

3.
A high diversity of pleurostomatid ciliates has been discovered in the last decade, and their systematics needs to be improved in the light of new findings concerning their morphology and molecular phylogeny. In this work, a new genus, Protolitonotus gen. n., and two new species, Protolitonotus magnus sp. n. and Protolitonotus longus sp. n., were studied. Furthermore, 19 novel nucleotide sequences of SSU rDNA, LSU rDNA and ITS1‐5.8S‐ITS2 were collected to determine the phylogenetic relationships and systematic positions of the pleurostomatid ciliates in this study. Based on both molecular and morphological data, the results demonstrated that: (i) as disclosed by the sequence analysis of SSU rDNA, LSU rDNA and ITS1‐5.8S‐ITS2, Protolitonotus gen. n. is sister to all other pleurostomatids and thus represents an independent lineage and a separate family, Protolitonotidae fam. n., which is defined by the presence of a semi‐suture formed by the right somatic kineties near the dorsal margin of the body; (ii) the families Litonotidae and Kentrophyllidae are both monophyletic based on both SSU rDNA and LSU rDNA sequences, whereas Amphileptidae are non‐monophyletic in trees inferred from SSU rDNA sequences; and (iii) the genera Loxophyllum and Kentrophyllum are both monophyletic, whereas Litonotus is non‐monophyletic based on SSU rDNA analyses. ITS1‐5.8S‐ITS2 sequence data were used for the phylogenetic analyses of pleurostomatids for the first time; however, species relationships were less well resolved than in the SSU rDNA and LSU rDNA trees. In addition, a major revision to the classification of the order Pleurostomatida is suggested and a key to its families and genera is provided.  相似文献   

4.
Generic boundaries among the genera Cheilosporum, Haliptilon, and Jania—currently referred to the tribe Janieae (Corallinaceae, Corallinales, Rhodophyta)—were reassessed. Phylogenetic relationships among 42 corallinoidean taxa were determined based on 26 anatomical characters and nuclear SSU rDNA sequence data for 11 species (with two duplicate plants) referred to the tribe Corallineae and 15 species referred to the tribe Janieae (two species of Cheilosporum, seven of Haliptilon, and six of Jania, with five duplicate plants). Results from our approach were consistent with the hypothesis that the tribe Janieae is monophyletic. Our data indicate, however, that Jania and Haliptilon as currently delimited are not monophyletic, and that Cheilosporum should not be recognized as an independent genus within the Janieae. Our data resolved two well‐supported biogeographic clades for the included Janieae, an Indian‐Pacific clade and a temperate North Atlantic clade. Among anatomical characters, reproductive structures reflected the evolution of the Janieae. Based on our results, three genera, Cheilosporum, Haliptilon, and Jania, should be merged into a single genus, with Jania having nomenclatural priority. We therefore propose new combinations where necessary of some species previously included in Cheilosporum and Haliptilon.  相似文献   

5.
Machaerotidae (Hemiptera: Auchenorrhyncha: Cercopoidea) is a taxonomically small but morphologically diverse family of spittlebugs with approximately 115 described species in 31 genera and an exclusively Palaeotropical distribution. Results are presented of the first molecular phylogenetic investigation of Machaerotidae, examining relationships among the currently recognized subfamilies and tribes, as well as determining the phylogenetic placement of the genera Enderleinia Schmidt, Neuromachaerota Schmidt, Labramachaerota Bell & Cryan, and Kyphomachaerota Bell & Cryan. DNA nucleotide sequence data from eight loci (12s rDNA, 16s rDNA, 18S rDNA, 28S rDNA, histone 2A, histone 3, wingless and NADH Dehydrogenase subunit 4) were analysed to reconstruct the phylogeny. The evidence generated in this study supports the following systematic conclusions: (i) Machaerotidae is a monophyletic family; (ii) Machaerotini, Hindoloidini (with the new inclusion of Kyphomachaerota), and Enderleiniini (excluding Kyphomachaerota and Apomachaerota Schmidt) are monophyletic tribes; (iii) the genus Apomachaerota was recovered as the most anciently diverged lineage of extant Machaerotidae, and a new subfamily (Apomachaerotinae subfam.n. ), is proposed on the basis of its phylogenetic placement as sister lineage to all other extant Machaerotidae.  相似文献   

6.
Partial sequences of nuLSU rDNA were obtained to investigate the phylogenetic relationships of Pyronemataceae, the largest and least studied family of Pezizales. The dataset includes sequences for 162 species from 51 genera of Pyronemataceae, and 39 species from an additional 13 families of Pezizales. Parsimony, ML, and Bayesian analyses suggest that Pyronemataceae is not monophyletic as it is currently circumscribed. Ascodesmidaceae is nested within Pyronemataceae, and several pyronemataceous taxa are resolved outside the family. Glaziellaceae forms the sister group to Pyronemataceae in ML analyses, but this relationship, as well as those of Pyronemataceae to the other members of the lineage, are not resolved with support. Fourteen clades of pyronemataceous taxa are well supported and/or present in all recovered trees. Several pyronemataceous genera are suggested to be non-monophyletic, including Anthracobia, Cheilymenia, Geopyxis, Humaria, Lasiobolidium, Neottiella, Octospora, Pulvinula, Stephensia, Tricharina, and Trichophaea. Cleistothecial and truffle or truffle-like ascomata forms appear to have evolved independently multiple times within Pyronemataceae. Results of these analyses do not support previous classifications of Pyronemataceae, and suggest that morphological characters traditionally used to segregate the family into subfamilial groups are not phylogenetically informative above the genus level.  相似文献   

7.
Molecular phylogenies often reveal that taxa circumscribed by phenotypical characters are not monophyletic. While re-examination of phenotypical characters often identifies the presence of characters characterizing clades, there is a growing number of studies that fail to identify diagnostic characters, especially in organismal groups lacking complex morphologies. Taxonomists then can either merge the groups or split taxa into smaller entities. Due to the nature of binomial nomenclature, this decision is of special importance at the generic level. Here we propose a new approach to choose among classification alternatives using a combination of morphology-based phylogenetic binning and a multiresponse permutation procedure to test for morphological differences among clades. We illustrate the use of this method in the tribe Thelotremateae focusing on the genus Chapsa, a group of lichenized fungi in which our phylogenetic estimate is in conflict with traditional classification and the morphological and chemical characters do not show a clear phylogenetic pattern. We generated 75 new DNA sequences of mitochondrial SSU rDNA, nuclear LSU rDNA and the protein-coding RPB2. This data set was used to infer phylogenetic estimates using maximum likelihood and Bayesian approaches. The genus Chapsa was found to be polyphyletic, forming four well-supported clades, three of which clustering into one unsupported clade, and the other, supported clade forming two supported subclades. While these clades cannot be readily separated morphologically, the combined binning/multiresponse permutation procedure showed that accepting the four clades as different genera each reflects the phenotypical pattern significantly better than accepting two genera (or five genera if splitting the first clade). Another species within the Thelotremateae, Thelotrema petractoides, a unique taxon with carbonized excipulum resembling Schizotrema, was shown to fall outside Thelotrema. Consequently, the new genera Astrochapsa, Crutarndina, Pseudochapsa, and Pseudotopeliopsis are described here and 39 new combinations are proposed.  相似文献   

8.
Molecular phylogenetic studies were carried out based on ITS-5.8S rDNA, the D1–D2 region of the large subunit rRNA gene, RPB2, and combined data of D1–D2 and RPB2 as well as these three genes on 36 species among 7 genera for Lachnum and allied genera in the family Hyaloscyphaceae. In the combined data of all three regions, seven strongly supported clades were obtained. The same clades were also recognized in most of the trees based on each gene, and the combined data of D1–D2 and RPB2, although some of them were not strongly supported. Four clades represented Albotricha, Brunnipila, Incrucipulum, and Lachnellula, respectively, whereas Lachnum was distributed to the remaining three clades. The molecular phylogenies strongly supported a group of species with granulate hairs, and we suggest the concept of Lachnaceae should be restricted to these species. Based on the molecular phylogenetic analysis, three new combinations—Incrucipulum longispineum, I. radiatum, and Lachnellula pulverulentum from Lachnum—are proposed.  相似文献   

9.
10.
The aim of this study was to improve our knowledge about the taxonomy and phylogeny of the family Saprolegniaceae, a group of water molds including several pathogens of plants, fish and crustacea. ITS and LSU rDNA were sequenced for representatives of forty species corresponding to ten genera (Achlya, Aphanomyces, Brevilegnia, Dictyuchus, Leptolegenia, Plectospira, Pythiopsis, Saprolegnia, Thraustotheca). Phenetic and cladistic analyses were then carried out. The species Brevilegnia bispora does not appear to belong to the family Saprolegniaceae. Plectospira myrianda clusters with Aphanomyces spp. and they constitute an ancestral group. (Thraustotheca clavata is closely related to the eccentric species of the genus Achlya. The genus Achlya appears polyphyletic, corroborating more or less the three known subgroups, defined by their sexual spore type (eccentric, centric and subcentric). The achlyoid type of spore dehiscence, shared by Aphanomyces and Achlya genera, is shown to be an ancestral character. The saprolegnioid, dictyoid and thraustothecoid types of spore dehiscence are derived characters but their relative evolutionary positions are not resolved.  相似文献   

11.
Nuclear‐encoded small subunit rDNA, 1506 group I intron, and internal transcribed spacer sequences were obtained from 39 strains representing five core desmid genera, Staurastrum, Staurodesmus Teil., Cosmarium Corda ex Ralfs, Xanthidium Ehr. ex Ralfs, and Euastrum Ehr. ex Ralfs (Desmidiaceae, Zygnematophyceae), and used individually and concatenated to assess phylogenetic relationships between putatively allied members of the family. To identify positional homology between divergent noncoding sequences, secondary structure models were generated and their reliability assessed by screening the alignment for compensating base changes. The phylogeny based on coding and noncoding sequence comparisons confidently resolved a monophyletic core of the genus Staurastrum but also revealed the artificial nature of the traditional genus. Twenty distinct species representing a wide range of morphotypes of Staurastrum formed a strongly supported generic clade that was further split into three well‐resolved lineages. The phylogenetic relationships revealed within Staurastrum were in conflict with all previous formal or informal classifications of the genus. The genera Staurodesmus and Cosmarium were shown to be highly polyphyletic, and some morphologically similar taxa displayed high sequence divergence that exceeded generic boundaries. Apparently, the taxonomic significance of some morphological characters in Staurastrum and other desmid genera has been greatly overestimated.  相似文献   

12.
A remarkable new genus and two new species of Mantispidae (Neuroptera) are described from the Oriental region. Allomantispa Liu, Wu, Winterton & Ohl gen.n. , currently including A. tibetana Liu, Wu & Winterton sp.n. and A. mirimaculata Liu & Ohl sp.n. The new genus is placed in the subfamily Drepanicinae based on a series of morphological characteristics and on the results of total evidence phylogenetic analyses. Bayesian and Parsimony analyses were undertaken using three gene loci (CAD, 16S rDNA and COI) combined with 74 morphological characters from living and fossil exemplars of Mantispidae (17 genera), Rhachiberothidae (two genera) and Berothidae (five genera), with outgroup taxa from Dilaridae and Osmylidae. The resultant phylogeny presented here recovered a monophyletic Mantispidae with ?Mesomantispinae sister to the rest of the family. Relationships among Mantispidae, Rhachiberothidae and Berothidae support Rhachiberothidae as a separate family sister to Mantispidae. Within Mantispidae, Drepanicinae are a monophyletic clade sister to Calomantispinae and Mantispinae. In a combined analysis, Allomantispa gen.n. was recovered in a clade comprising Ditaxis McLachlan from Australia, and two fossil genera from the Palaearctic, ?Promantispa Panfilov (Kazakhstan; late Jurassic) and ?Liassochrysa Ansorge & Schlüter (Germany; Jurassic), suggesting a highly disjunct and relictual distribution for the family. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:464B06E8‐47E6‐482E‐8136‐83FE3B2E9D6B .  相似文献   

13.
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   

14.
To determine a suitable DNA barcode for the genus Neonectria, the internal transcribed spacer rDNA, β-tubulin, EF-1α, and RPB2 genes were selected as candidate markers. A total of 205 sequences from 19 species of the genus were analyzed. Intra- and inter-specific divergences and the ease of nucleotide sequence acquisition were treated as criteria to evaluate the feasibility of a DNA barcode. Our results indicated that any single gene among the candidate markers failed to serve as a successful barcode, while the combination of the partial EF-1α, and RPB2 genes recognized all species tested. We tentatively propose the combined partial EF-1α and RPB2 genes as a DNA barcode for the genus. During this study, two cryptic species were discovered, based on the combined data of morphology and DNA barcode information. We described and named these two new species N. ditissimopsis and N. microconidia.  相似文献   

15.
Bayesian and maximum‐likelihood (ML) analyses of the combined multigene data (nuclear SSU rDNA, and plastid SSU and LSU rDNA) were conducted to evaluate the phylogeny of photosynthetic euglenoids. The combined data set consisted of 108 strains of photosynthetic euglenoids including a colorless sister taxon. Bayesian and ML analyses recovered trees of almost identical topology. The results indicated that photosynthetic euglenoids were divided into two major clades, the Euglenaceae clade (Euglena, Euglenaria, Trachelomonas, Strombomonas, Monomorphina, Cryptoglena, Colacium) and the Phacaceae clade (Phacus, Lepocinclis, Discoplastis). The Euglenaceae clade was monophyletic with high support and subdivided into four main clades: the Colacium, the Strombomonas and Trachelomonas, the Cryptoglena and Monomorphina, and the Euglena and Euglenaria clades. The genus Colacium was positioned at the base of the Euglenaceae and was well supported as a monophyletic lineage. The loricate genera (Strombomonas and Trachelomonas) were located at the middle of the Euglenaceae clade and formed a robust monophyletic lineage. The genera Cryptoglena and Monomorphina also formed a well‐supported monophyletic clade. Euglena and the recently erected genus Euglenaria emerged as sister groups. However, Euglena proxima branched off at the base of the Euglenaceae. The Phacaceae clade was also a monophyletic group with high support values and subdivided into three clades, the Discoplastis, Phacus, and Lepocinclis clades. The genus Discoplastis branched first, and then Phacus and Lepocinclis emerged as sister groups. These genera shared a common characteristic, numerous small discoid chloroplasts without pyrenoids. These results clearly separated the Phacaceae clade from the Euglenaceae clade. Therefore, we propose to limit the family Euglenaceae to the members of the Euglena clade and erect a new family, the Phacaceae, to house the genera Phacus, Lepocinclis, and Discoplastis.  相似文献   

16.
Representatives of the monophyletic Trentepohliales are widely distributed in the tropics, subtropics, and temperate regions worldwide. They grow in soil, or are epilithic, epiphytic or endophytic. The family comprises approximately 70 species placed in at least four genera (Trentepohlia, Cephaleuros, Phycopeltis and Stomatochroon), with Trentepohlia sensu lato (including Printzina and Physolinum) accounting for half of the species in this family. PCR amplification and sequencing of the 18 SSU rDNA of 18 isolates of the Trentepohliaceae were used to assess the monophyly of the genus Cephaleuros and to determine the phylogenetic relationships among species of Trentepohlia sensu lato. Distance, Parsimony, and Maximum Likelihood analyses indicate that Trentepohlia sensu lato is basal and includes two species recently transferred to Phycopeltis (P. umbrina) and Printzina (P. lagenifera). In contrast, Cephaleuros is a derived monophyletic clade. Analysis of isolates of C. virescens, from the USA, Taiwan, and South Africa indicate that this taxon may consist of different species sharing a convergent morphology. The results of this study have implications for the taxonomy of the genera.  相似文献   

17.
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   

18.
19.
In the present study, we investigated the intrageneric and intergeneric phylogenetic relationships of the heterotrophic marine dinoflagellate genus Protoperidinium. Using single‐cell polymerase chain reaction methods, we determined small subunit ribosomal RNA gene sequences for 10 Protoperidinium species belonging to four sections and two subgenera. Phylogenetic trees were constructed using maximum parsimony, neighbor joining and maximum likelihood methods. We found intraspecific variability of small subunit rDNA sequences in Protoperidinium conicum (Gran) Balech, Protoperidinium crassipes (Kofoid) Balech and Protoperidinium denticulatum (Gran et Braarud) Balech, but not in other species. The small subunit rDNA phylogeny revealed that the genus is monophyletic, but its phylogenetic position within the Dinophyceae could not be determined because of ambiguous basal topologies. Within the genus Protoperidinium, species of the subgenus Archaeperidinium with two anterior intercalary plates (2a) were shown to be monophyletic, but species of the subgenus Protoperidinium with three anterior intercalary plates (3a) were resolved as paraphyletic. The sections Avellana, Divergentia and Protoperidinium were shown to be monophyletic, while the section Conica was paraphyletic. Based on the trees obtained in the present study, most of the traditionally defined sections are supported by molecular phylogeny. It was also indicated that the section Avellana evolved from one of the Conica‐type dinoflagellates.  相似文献   

20.
Dung beetle species belonging to the worldwide tribe Canthonini (Scarabaeidae) and occurring in Madagascar are all endemic to that island. The Malagasy Canthonini form three lineages, one of which is the group Longitarsi that includes five genera. The phylogenetic relationships of Malagasy Canthonini are not fully resolved and only few species of Longitarsi have been included in previous studies. Here we infer the phylogenetic relationships within the Longitarsi group using molecular data and together with morphological examination revise the systematics of the group. The five genera of the Longitarsi group form one monophyletic clade and thus we suggest the synonymization of the younger genera Sikorantus, Phacosomoides, Madaphacosoma and Aleiantus; with the oldest genus belonging to this clade Epactoides. We describe two new species: Epactoides jounii sp. n and Epactoides mangabeensis sp. n. Most of the species of Longitarsi inhabit the eastern rainforests, with very low local species diversity and highly restricted geographical ranges. In the group Longitarsi four species are wingless. The loss of wings has evolved at least twice, at high altitude along the mountain range.  相似文献   

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