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1.
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   

2.
The Munidopsidae, one of three squat lobster families in the Galatheoidea, contains the deepest dwelling squat lobsters, with some occurring at abyssal depths. Munidopsids were formerly divided into two subfamilies: Shinkaiinae, for the unusual hydrothermal vent genus Shinkaia; and Munidopsinae for remaining taxa. Four munidopsid genera are currently recognised (Shinkaia, Leiogalathea, Galacantha and Munidopsis) but the largest genus, Munidopsis, is highly diverse morphologically, with multiple genera or subgenera currently in its synonymy. Phylogenetic studies of galatheoids focussed on high level relationships indicate that Leiogalathea is sister to other munidopsids, but the position of Shinkaia with respect to Munidopsis and Galacantha is unclear, as is the reciprocal monophyly of the latter two genera. Phylogenetic analyses of the Munidopsidae based on mitochondrial 16S and COI sequences, sampling all current genera (including the majority of the formerly recognised subgenera), indicate that the generic and former subfamily classifications do not reflect the phylogeny. Shinkaia and Galacantha clades are nested within Munidopsis rendering the genus paraphyletic and the bi-subfamily classification phylogenetically invalid. Many of the Munidopsis clades recovered, however, correspond well to formerly recognised genera or subgenera, indicating good prospects for a natural subdivision of Munidopsis.  相似文献   

3.
Merlin M. WHITE   《Mycological Research》2006,110(9):1011-1024
The Harpellales (Trichomycetes) are endosymbiotic microfungi, mostly unculturable and predominantly associated with larval aquatic insects worldwide. Molecular phylogenies including ‘gut fungi’ have included at most only four axenic isolates of the 38 genera of Harpellales. Cladistic analyses were used to infer the phylogeny of the Harpellales using partial 18S or 28S nu-rRNA sequences generated for 16 genera of Harpellales, with 64 of 72 sequences generated from unculturable samples. Both analyses placed Orphella outside an otherwise monophyletic group of Harpellales, more closely allied to the Kickxellales. The current classification recognizing two families is not corroborated and continued use of the family Legeriomycetaceae may not be supportable. The largest genera of Harpellales, Smittium and Stachylina, were polyphyletic and the 28S rRNA sequences separate Smittium culisetae from the remainder of its genus. The cladograms did not support the consistent mapping of important morphological taxonomic characters, including trichospore shape and zygospore type or appendage numbers for both. This study demonstrates the use of microscopic thalli from host guts for molecular phylogenies and suggests the need for more data from the remaining Harpellales, especially with the future inclusion of protein-coding genes.  相似文献   

4.
A molecular phylogenetic analysis of Cynoglottis was performed to evaluate previous hypotheses based on non-molecular evidence concerning the position of this genus within Boraginaceae tribe Boragineae. ITS-5.8S and trnLUAA sequences from the nuclear and chloroplast non-coding genomes were obtained for four Cynoglottis taxa and selected members of the related genera Anchusa, Anchusella, Gastrocotyle, Brunnera and Pentaglottis. Cynoglottis is monophyletic, but neither trnL nor ITS support a close relationship with Brunnera, unlike previously supposed on morphological grounds. Brunnera is, instead, related to the southwestern European monotypic genus Pentaglottis, with which it forms a basal clade. ITS-5.8S sequences show that Anchusa thessala, a southeastern European annual species of Anchusa subg. Buglossellum, is sister to Cynoglottis and that the two taxa form a clade which also includes the Balkan endemic Gastrocotyle macedonica. Species of Anchusa subg. Anchusa form a separate lineage with high bootstrap support, suggesting that this heterogeneous genus is paraphyletic with respect to Cynoglottis. ITS sequences also discriminate between the Balkan-Apenninic diploid C. barrelieri and the Anatolian tetraploid C. chetikiana, albeit with low support. The molecular results are discussed in the light of karyological, morphological and chorological aspects.This work has been supported by M.I.U.R. 40% 2003 and the University of Firenze.  相似文献   

5.
6.
广义无心菜属(Arenaria L.s.l.)是石竹科(Caryophyllaceae)中分类较为困难的大属之一,基于分子系统学研究结果该属目前已被拆分为多属。基于形态学证据,桃色无心菜(Arenaria melandryoides Edgew.)被置于无心菜属齿瓣亚属[subg.Odontostemma (G.Don) Williams]、齿瓣无心菜属(Odontostemma Benth.ex G.Don)或独缀草属[Shivparvatia (Edgew.) PusalkarD.K.Singh]之中,但都缺少分子系统学证据的支持。基于ITS序列重建了繁缕族(Alsineae)系统发育关系,结果表明:目前所界定的齿瓣无心菜属并非单系,桃色无心菜应纳入独缀草属的范畴。此外,还支持将传统无心菜属齿瓣亚属中漆姑无心菜(A.saginoides Maxim.)、匙叶无心菜(A.spathulifolia C.Y.Wu ex L.H.Zhou)及云南无心菜(A.yunnanensis Franch.)归入齿瓣无心菜属的处理,以及将单花亚属中红花无心菜(A.rhodantha PaxK.Hoffmann)归入独缀草属的处理。形态特征上,花朵单生于枝端这一特征可作为独缀草属区别于齿瓣无心菜属的重要识别特征。  相似文献   

7.
To more confidently assess phylogenetic relationships among astome ciliates, we obtained small subunit (SSU) rRNA sequences from nine species distributed in six genera and three families: Almophrya bivacuolata, Eudrilophrya complanata, Metaracoelophrya sp. 1, Metaracoelophrya sp. 2, Metaracoelophrya intermedia, Metaradiophrya sp., Njinella prolifera, Paraclausilocola constricta n. gen., n. sp., and Paraclausilocola elongata n. sp. The two new species in the proposed new clausilocolid genus Paraclausilocola n. gen. are astomes with no attachment apparatus, two files of contractile vacuoles, and an arc-like anterior suture that has differentiations of thigmotactic ciliature on the anterior ends of the left kineties of the upper surface. Phylogenetic analyses were undertaken using neighbor-joining, Bayesian inference, maximum likelihood, and maximum parsimony. The nine species of astomes formed a strongly supported clade, showing the subclass Astomatia to be monophyletic and a weakly supported sister clade to the scuticociliates. There were two strongly supported clades within the astomes. However, genera assigned to the same family were found in different clades, and genera assigned to the same order were found in both clades. Thus, astome taxa appear to be paraphyletic when morphology is used to assign species to genera.  相似文献   

8.
Gnomonia fragariae is a poorly studied ascomycete belonging to Diaporthales. Originally G. fragariae was considered a saprophyte occurring on dead tissues of strawberry plants. Recently this fungus was found in Latvia and Sweden, and it was proven to be the cause of severe root rot and petiole blight of strawberry. Thirteen isolates of this pathogen and several other Gnomonia species occurring on rosaceous hosts were characterized by molecular analysis using nucleotide sequences of partial LSU rRNA gene and the total ITS region. The homologous regions from relevant diaporthalean taxa available in the GenBank were also included and compared with the taxa sequenced in this study. Phylogenetic analyses revealed that G. fragariae, G. rubi, and Gnomonia sp. (CBS 850.79) were genetically different from G. gnomon, the type species of the genus, and other members of Gnomoniaceae. The analyses showed that G. fragariae and Hapalocystis were genetically very closely related, forming a phylogenetic clade, which is possibly presenting a new family in the Diaporthales. Morphological comparisons of the Gnomonia species on the basis of commonly used criteria for the taxonomy of Diaporthales, so far did not reveal any evident features for the polyphyletic status of Gnomonia.  相似文献   

9.
A cultivation-based approach was employed to compare the culturable actinobacterial diversity associated with five marine sponge species (Craniella australiensis, Halichondria rugosa, Reniochalina sp., Sponge sp., and Stelletta tenuis). The phylogenetic affiliation of the actinobacterial isolates was assessed by 16S rDNA-RFLP analysis. A total of 181 actinobacterial strains were isolated using five different culture media (denoted as M1–M5). The type of medium exhibited significant effects on the number of actinobacteria recovered, with the highest number of isolates on M3 (63 isolates) and the lowest on M1 (12 isolates). The genera isolated were also different, with the recovery of three genera on M2 and M3, and only a single genus on M1. The number of actinobacteria isolated from the five sponge species was significantly different, with a count of 83, 36, 30, 17, and 15 isolates from S. tenuis, H. rugosa, Sponge sp., Reniochalina sp., and C. australiensis, respectively. M3 was the best isolation medium for recovery of actinobacteria from S. tenuis, H. rugosa, and Sponge sp., while no specific medium preference was observed for the recovery of actinobacteria from Reniochalina sp., and C. australiensis. The RFLP fingerprinting of 16S rDNA genes digested with HhaI revealed six different patterns, in which 16 representative 16S rDNAs were fully sequenced. Phylogenetic analysis indicated that 12 strains belong to the group Streptomyces, three strains belong to Pseudonocardia, and one strain belongs to Nocardia. Two strains C14 (from C. australiensis) and N13 (from Sponge sp.) have only 96.26% and 96.27% similarity to earlier published sequences, and are therefore potential candidates for new species. The highest diversity of three actinobacteria genera was obtained from Sponge sp., though the number of isolates was low. Two genera of actinobacteria, Streptomyces, and Pseudonocardia, were isolated from both S. tenuis and C. australiensis. Only the genus of Streptomyces was isolated from H. rugosa and Reniochalina sp. Sponge species have been demonstrated here to vary as sources of culturable actinobacterial diversity, and the methods for sampling such diversity presented may be useful for improved sampling of such diversity.  相似文献   

10.
The phylogenetic relationships of Peniocereus (Cactaceae) species were studied using parsimony analyses of DNA sequence data. The plastid rpl16 and trnL-F regions were sequenced for 98 taxa including 17 species of Peniocereus, representatives from all genera of tribe Pachycereeae, four genera of tribe Hylocereeae, as well as from three additional outgroup genera of tribes Calymmantheae, Notocacteae, and Trichocereeae. Phylogenetic analyses support neither the monophyly of Peniocereus as currently circumscribed, nor the monophyly of tribe Pachycereeae since species of Peniocereus subgenus Pseudoacanthocereus are embedded within tribe Hylocereeae. Furthermore, these results show that the eight species of Peniocereus subgenus Peniocereus (Peniocereus sensu stricto) form a well-supported clade within subtribe Pachycereinae; P. serpentinus is also a member of this subtribe, but is sister to Bergerocactus. Moreover, Nyctocereus should be resurrected as a monotypic genus. Species of Peniocereus subgenus Pseudoacanthocereus are positioned among species of Acanthocereus within tribe Hylocereeae, indicating that they may be better classified within that genus. A number of morphological and anatomical characters, especially related to the presence or absence of dimorphic branches, are discussed to support these relationships.  相似文献   

11.
In this study two actinomycete strains were isolated in Cape Town (South Africa), one from a compost heap (strain 202GMOT) and the other from within the fynbos-rich area surrounded by the horseracing track at Kenilworth Racecourse (strain C2). Based on 16S rRNA gene sequence BLAST analysis, the strains were identified as members of the genus Nocardia. Phylogenetic analysis showed that the strains clustered together and are most closely related to Nocardia flavorosea NRRL B-16176T, Nocardia testacea JCM 12235T, Nocardia sienata IFM 10088T and Nocardia carnea DSM 43397T. This association was also supported by gyrB based phylogenetic analysis. The results of DNA–DNA hybridization and physiological tests allowed genotypic and phenotypic differentiation of both strains 202GMOT and C2 from related species. However, their high DNA relatedness showed that they belong to the same species. Strain 202GMOT was selected as the type strain to represent this novel species, for which the name Nocardia rhamnosiphila is proposed (=DSM 45147T = NRRL B-24637T).  相似文献   

12.
Dendrobium sect. Dendrocoryne is a difficult taxonomic group of allied species and species complexes, occurring on the eastern Australian coastline, Lord Howe Island and New Caledonia. Significant morphological characters were assessed from all key areas of the distribution range. Patterns of variation between species, varieties and hybrids were investigated by principal coordinate analysis. The analyses affirm 12 species in the sect. Dendrocoryne described by Schlechter (1912, 1982) and Dockrill (1969, 1992), including a cluster of small statured D. gracilicaule, D. adae, D. fleckeri, and D. finniganense, and three variable species complexes – D. speciosum, D. kingianum and D. tetragonum. Recently described D. finniganense and D. callitrophilum are interpreted as members of the section. Phylogenetic relationships are presented based on parsimony analysis of 31 morphological characters. Analyses do not support proposals to recognize new genera for D. tetragonum, D. callitrophilum and D. aemulum, or to create new species within D. tetragonum, D. jonesii, D. speciosum and D. kingianum. The phylogeny indicates that rainforest taxa are earlier lineages and xerophytic taxa are more derived.  相似文献   

13.
Gliridae is a small family of rodents including three subfamilies: the Eurasian Glirinae (with three genera) and Leithiinae (with four genera) and the African Graphiurinae (with a single genus). Phylogenetic relationships among these eight genera are not fully resolved based on morphological characters. Moreover, the genus Graphiurus is characterized by numerous peculiar features (morphological characters and geographical distribution), raising the question of its relationships to the family Gliridae. The phylogenetic position of Graphiurus and the intra-Gliridae relationships are here addressed by a molecular analysis of 12S RNA and cytochrome b mitochondrial gene sequences for six glirid genera. Phylogenetic analyses are performed with three construction methods (neighbor-joining, maximum parsimony and maximum likelihood) and tests of alternative topologies with respect to the most likely. Our analyses reveal that Graphiurus is clearly a member of the Gliridae, refuting the hypothesis that the family could be paraphyletic. Among Gliridae, phylogenetic relationships are poorly resolved: the Leithiinae could be monophyletic, there is no support for the subfamily Glirinae, and the closest relative of Graphiurus is not identified. The inclusion of Graphiurus among Gliridae allows us to postulate that its hystricomorphous condition has been achieved convergently with other hystricomorphous rodents.  相似文献   

14.
The new genus and species Teracosphaeria petroica is described for a perithecial ascomycete and its anamorph occurring on decayed wood collected in New Zealand. The fungus produces immersed, non-stromatic ceratosphaeria-like perithecia in nature, with hyaline, septate ascospores produced in unitunicate, non-amyloid asci. The anamorph produced in vitro is phialophora-like with lightly pigmented phialides terminating in flaring, deep collarettes that are often noticeably brown with conspicuous periclinal thickening. Phylogenetic analysis of LSU rDNA sequence data indicates that this fungus is distinct from morphologically similar fungi classified in the Chaetosphaeriales, the Trichosphaeriales or the Magnaporthaceae. It forms a monophyletic group with recently described, chaetosphaeria-like ascomycetes, such as the pyrenomycete genus Mirannulata, and shows affinity with the anamorphic species Dictyochaeta cylindrospora. The usefulness of describing anamorph genera for morphologically reduced anamorphs, when anamorph characteristics are actually part of the holomorph diagnosis, is discussed. An apparently contradictory example of the so-called Cordana and Pseudobotrytis anamorphs of Porosphaerella spp. is also discussed.  相似文献   

15.
Phylogenetic analyses of the monocotyledonous genera Leucojum and Galanthus (Amaryllidaceae, Asparagales), using plastid (trnL-F and matK) and largely non-coding nuclear ribosomal (ITS) DNA sequences show the two to be closely related to Lapiedra, Narcissus, Vagaria, Pancratium and Sternbergia. We compare the results obtained with a combined parsimony analysis of these nucleotide sequences with that of a matrix of morphological characters. The sampling included all species of Leucojum and most species of Galanthus (representing all series and subseries of the genus) and used as outgroup the above mentioned genera of Amaryllidaceae shown to be close relatives. The plastid, nuclear and morphological data were analysed independently and in combination, showing that the boundaries between the two genera are not appropriate. Galanthus is monophyletic but embedded in Leucojum. On the basis of chromosome numbers and floral characters Leucojum has been previously divided into four subgenera, which have been accepted as genera by some authors. In our phylogenetic analyses (separate as well as combined), Leucojum species are separated in two primary clades corresponding to L. subgenera Ruminia + Acis and L. Leucojum + Aerosperma. The taxonomic implications of this pattern are discussed, and an alternative classification is proposed. Finally, biogeographic relationships of species of both Leucojum and Galanthus are discussed, emphasising the possible origin of the narrowly distributed taxa of Leucojum relative to the widespread species.  相似文献   

16.
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   

17.
A new genus of a deep-sea ascomycete with one new species, Alisea longicolla, is described based on analyses of 18S and 28S rDNA sequences and morphological characters. A. longicolla was found together with Oceanitis scuticella, on small twigs and sugar cane debris trawled from the bottom of the Pacific Ocean off Vanuatu Islands. Molecular and morphological characters indicate that both fungi are members of Halosphaeriaceae. Within this family, O. scuticella is phylogenetically related to Ascosalsum and shares similar ascospore morphology and appendage ontogeny. The genus Ascosalsum is considered congeneric with Oceanitis and Ascosalsum cincinnatulum, Ascosalsum unicaudatum and Ascosalsum viscidulum are transferred to Oceanitis, an earlier generic name.  相似文献   

18.
Most of the species of the family Rubiaceae with flowers arranged in head inflorescences are currently classified in three distantly related tribes, Naucleeae (subfamily Cinchonoideae) and Morindeae and Schradereae (subfamily Rubioideae). Within Morindeae the type genus Morinda is traditionally and currently circumscribed based on its head inflorescences and syncarpous fruits (syncarps). These characters are also present in some members of its allied genera, raising doubts about the monophyly of Morinda. We perform Bayesian phylogenetic analyses using combined nrETS/nrITS/trnT-F data for 67 Morindeae taxa and five outgroups from the closely related tribes Mitchelleae and Gaertnereae to rigorously test the monophyly of Morinda as currently delimited and assess the phylogenetic value of head inflorescences and syncarps in Morinda and Morindeae and to evaluate generic relationships and limits in Morindeae. Our analyses demonstrate that head inflorescences and syncarps in Morinda and Morindeae are evolutionarily labile. Morinda is highly paraphyletic, unless the genera Coelospermum, Gynochthodes, Pogonolobus, and Sarcopygme are also included. Morindeae comprises four well-supported and morphologically distinct major lineages: Appunia clade, Morinda clade (including Sarcopygme and the lectotype M. royoc), Coelospermum clade (containing Pogonolobus and Morinda reticulata), and Gynochthodes–Morinda clade. Four possible alternatives for revising generic boundaries are presented to establish monophyletic units. We favor the recognition of the four major lineages of Morindeae as separate genera, because this classification reflects the occurrence of a considerable morphological diversity in the tribe and the phylogenetic and taxonomic distinctness of its newly delimited genera.  相似文献   

19.
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   

20.
Rhizobia are bacteria that form nitrogen-fixing nodules on the roots, or occasionally the shoots, of legumes. There are currently more than a dozen validly named species, but the true number of species is probably orders of magnitude higher. The named species are listed and briefly discussed. Sequences of the small subunit ribosomal RNA (SSU or 16S rRNA) support the well-established subdivision of rhizobia into three genera: Rhizobium, Bradyrhizobium, and Azorhizobium. These all lie within the alpha subdivision of the Proteobacteria, but on quite distinct branches, each of which also includes many bacterial species that are not rhizobia. It has been clear for several years that Rhizobium, on this definition, is still too broad and is polyphyletic: there are many non-rhizobia within this radiation. Recently, therefore, it has been suggested that this genus should be split into four genera, namely Rhizobium (R. leguminosarum, R. tropici, R. etli), Sinorhizobium (S. fredii, S. meliloti, S. teranga, S. saheli), Mesorhizobium (M. loti, M. huakuii, M ciceri, M. tianshanense, M. mediterraneum), and a fourth, unnamed, genus for the current R. galegae. The evidence and pros and cons are reviewed.  相似文献   

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