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1.
A taxonomic revision ofVerbesina sect.Ochractinia is presented. 40 species plus 7 additional infraspecific taxa are recognized. A table of the distribution of the species, key to the species and synonymy are included. Relationships to other sections ofVerbesina and species relationships within sect.Ochractinia are discussed.  相似文献   

2.
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   

3.
Phylogenetic analysis of noncoding trnL plastid DNA sequences and morphological data for 43 species of Zygophylloideae, representing most of the morphological and geographical variation in the subfamily, indicates that the currently recognised genera Augea (monotypic, southern Africa), Tetraena (monotypic, China), and Fagonia (c. 30 species, widespread), are embedded in Zygophyllum (c. 150 species, widespread). A generic classification based on six monophyletic and morphologically distinctive entities is proposed: Roepera with c. 60 species in Australia and southern Africa, Zygophyllum with c. 50 species in Asia, Tetraena with c. 40 species in Africa and Asia, Augea with a single species in southern Africa, Melocarpum with two species in the Horn of Africa region, and Fagonia with c. 30 species in both the Old and the New World. Scanning electron microscopy studies of testa structure provided important characters for the delimitation of some genera. New combinations (61) are made in Roepera, a resurrected genus originally described from Australia, one new name is proposed in Zygophyllum, 35 new combinations are made in Tetraena, and two new combinations are made in Melocarpum (previously Zygophyllum sect. Melocarpum).  相似文献   

4.
seventeen new species and combinations are proposed in the generaChondrorhyncha, Cischweinfia, Cochlioda, Eloyella, Encyclia, Kefersteinia, Koellensteinia, Macroclinium, Rodriguezia, Solenidiopsis, andStenia. All new species are illustrated. A key is provided for 2-flowered species ofMacroclinium, PeruvianSigmatostalix, and PeruvianStenia. Solenidium (Solenidiopsis) peruvianum Schltr. is lectotypified.  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.
Polytretophora macrospora is introduced based on specimens from two species ofPandanus in Seychelles. The new species is compared with currently accepted species. A key and a comparative synopsis toPolytetophora species are provided. Numerous specimens ofP. calcarata, collected on members of the Pandanaceae from Australia, Fiji, Hong Kong, Malaysia, New Caledonia, Palau, Philippines, Seychelles and Solomon Islands are also reported, along withP. dendroidea onPandanus sp. from Malaysia.  相似文献   

7.
Fourteen species of Characeae were analyzed for their free amino acids. This study, in combination with previous results (Sakanoet al., 1984) showed that all the species that belong to the generaChara (6 species),Lamprothamnium (1 species),Nitellopsis (1 species),Lychnothammus (1 species) and 5Nitella species of the members of the subsectionAnarthrodactylae contained a large amount of isoasparagine. In contrast, no isoasparagine was found in the species belonging toTolypella (3 species) and otherNitella (7 species). Presence of isoasparagine in some species of Characeae (N. flexillis andNitellopsis obtusa) was found to be independent of their localities (Japan, Canada and England). Species lacking isoasparagine (N. oligogyra and N. axilliformis) did not produce isoasparagine even under the condition that induced a great increase of this amino acid in the species that contained it (C. corallina andN. flexilis). These results indicate that isoasparagine is a distinct taxonomic marker and suggest that theNitella species of the subsectionAnarthrodactylae are the most primitive group inNitelleae in that they share synthesis and accumulation of isoasparagine withChareae and, hence, support the view (Kasaki, 1964) that the subsection may be treated as an independent genus.  相似文献   

8.
The family Sordariaceae incorporates a number of fungi that are excellent model organisms for various biological, biochemical, ecological, genetic and evolutionary studies. To determine the evolutionary relationships within this group and their respective phylogenetic placements, multiple-gene sequences (partial nuclear 28S ribosomal DNA, nuclear ITS ribosomal DNA and partial nuclear β-tubulin) were analysed using maximum parsimony and Bayesian analyses. Analyses of different gene datasets were performed individually and then combined to generate phylogenies. We report that Sordariaceae, with the exclusion Apodus and Diplogelasinospora, is a monophyletic group. Apodus and Diplogelasinospora are related to Lasiosphaeriaceae. Multiple gene analyses suggest that the spore sheath is not a phylogenetically significant character to segregate Asordaria from Sordaria. Smooth-spored Sordaria species (including so-called Asordaria species) constitute a natural group. Asordaria is therefore congeneric with Sordaria. Anixiella species nested among Gelasinospora species, providing further evidence that non-ostiolate ascomata have evolved from ostiolate ascomata on several independent occasions. This study agrees with previous studies that show heterothallic Neurospora species to be monophyletic, but that homothallic ones may have a multiple origins. Although Gelasinospora and Neurospora are closely related and not resolved as monophyletic groups, there is insufficient evidence to place currently accepted Gelasinospora and Neurospora species into the same genus.  相似文献   

9.
RFLPs of cpDNA were examined for 18 species ofAster, six species ofKalimeris, two species ofMiyamayomena and one species and one variety ofHeteropappus from Japan, using 16 restriction endonucleases. Approximately 275 restriction sites were surveyed, and a total of 74 restriction site mutations was detected, and 31 of these were phylogenetically informative. Sixteen most parsimonious trees constructed from Wagner parsimony analysis indicated the polyphyly ofKalimeris andMiyamayomena sensu Kitamura;K. miqueliana belongs to a different clade from the remaining species ofKalimeris, and two species ofMiyamayomena did not make a single clade. This result suggests that the shortening or loss of pappus have happened parallelly in different evolutionary lineages. We must be careful to assess the pappus character in taxonomy and phylogeny, and it is desirable to examine their phylogenetic relationships using a molecular data.  相似文献   

10.
The sinipercids represent a group of 12 species of freshwater percoid fish, including nine in Siniperca and three species in Coreoperca. Despite several classification attempts and a preliminary molecular phylogeny, the phylogenetic relationships and systematic position of sinipercids remained still unsolved. The complete cytochrome b gene sequences from nine sinipercid species four non-sinipercid fish species were cloned, and a total of 12 cyt b sequences from 10 species of sinipercids and 11 cyt b sequences from 10 species of non-sinipercid fish also in Perciformes were included in the phylogenetic analysis. As expected, the two genera Siniperca and Coreoperca within sinipercids are recovered as monophyletic. However, nine species representing Moronidae, Serranidae, Centropomidae, Acropomatidae, Emmelichtyidae, Siganidae and Centrarchidae included in the present study are all nested between Coreoperca and Siniperca, which provides marked evidence for a non-monophyly of sinipercid fishes. Coreoperca appears to be closest to Centrachus representing the family Centrarchidae. Coreoperca whiteheadi and C. herzi are sibling species, which together are closely related to C. kawamebari. In the Siniperca, the node between S. roulei and the remaining species is the most ancestral, followed by that of S. fortis. S. chuatsi and S. kneri are sibling species, sister to S. obscura. However, the sinipercids do not seem to have a very clear phylogenetic history, for different methods of phylogenetic reconstruction result in different tree topologies, and the only conclusive result in favor of a paraphyletic origin of the two sinipercid genera is the parametric bootstrap test. The paraphyly of Sinipercidae may suggest that the “synapomorphs” such as cycloid scales, upon which this family is based, were independently derived at least twice within sinipercid fishes, and further study should be carried out to include the other two Siniperca species and to incorporate other genes. Handling editor: C. Sturmbauer  相似文献   

11.
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   

12.
Sixteen new species are proposed in the generaAckermania, Dressleria, Epidendrum, Maxillaria, Oncidium, Rodriguezia, Sigmatostalix, andTrigonidium. All new species are illustrated.Maxillaria vittariifolia L. O. Williams is newly recorded for Peru. A key is provided forTrigonidium of Peru.Trigonidium loretoense Schltr. andT. peruvianum Schltr. are lectotypified.  相似文献   

13.
A preliminary account of Entolomataceae from Costa Rica is presented. Three new taxa are described, two inClitopilus, one inRhodocybe, and three new combinations are proposed inInocephalus. Five taxa ofClitopilus are reported for the first time from Costa Rica and a key to species is provided. Four species ofRhodocybe are discussed and a key to the six species known from Costa Rica is also provided.Alboleptonia earlei, Inocephalus murraii, Inocephalus quadratum, Rhodocybe incarnata andRhodocybe pseudonitellina are now known to occur in Costa Rica.  相似文献   

14.
Polystichum is one of the largest and most taxonomically complex fern genera in China. The evolutionary relationships of Chinese Polystichum and related genera, and the relationship between our Polystichum phylogeny and ecogeographic distribution, were tested by the use of DNA sequence data. Fifty-one species of Polystichum and 21 species in allied genera were sequenced for the plastid intergenic spacers rps4-trnS and trnL-F. Maximum parsimony and Bayesian phylogenetic analyses of both individual and combined data sets showed that Chinese Polystichum as commonly recognized was paraphyletic: one clade (the CCPC clade) included Cyrtomidictyum lepidocaulon, two Cyrtogonellum species, three Cyrtomium species, and a small number of Polystichum species usually occurring on limestone. A second clade, Polystichum sensu stricto, included the remainder of the Polystichum species; these often occur on non-limestone substrates. The remaining Cyrtomium species formed the third clade. Three subclades resolved within Polystichum sensu stricto (s.s.) clade do not correspond with recent sectional classifications, and we outline the issues relevant to a new classification for the genus. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

15.
Approximately one-fourth of the more than 900 world-wide distributed Salvia species (Lamiaceae) is ornithophilous. With few exceptions they occur in the New World, being predominantly pollinated by hummingbirds. In the Old World only Salvia africana-lutea and the recently described Salvia thermarum, both from the Cape Province of South Africa, were observed to be pollinated by sunbirds and white-eyes. Among the 23 South African Salvia species Salvia lanceolata is a further candidate for being bird pollinated. For the first time we describe and illustrate its pollination by Nectarinia chalybea and Zosterops pallidus. We compare the ornithophilous syndrome of the three mentioned Salvia species and relate them to the morphological fitting of the most common nectarivorous birds of the Southwestern Cape (Cape peninsula to Worcester). We conclude that each of the birds could act as a pollinator and that the three co-occurring Salvia species are not mechanically isolated from each other. The degree of specialisation towards bird pollination, possible hybridisation events and evolution of bird pollination in South African Salvia species are discussed.  相似文献   

16.
Based on the results of morphological and DNA sequence (partial D1–D3/D7–D8 nuLSU and partial nuSSU-ITS1-5.8S rDNA) data, three species of Plasmopara are revised and reclassified. A species of Plasmopara parasitic on Scorzonera, invalidly published several times, is assigned to a new genus and species under Novotelnova scorzonerae. Plasmopara euphrasiae sp. nov. is segregated from P. densa, and P. centaureae-mollis is revised and relegated to synonymy of Bremia centaureae. All taxa are described and illustrated.  相似文献   

17.
In the present study phylogenetic relationships of the genus Stereocaulon (lichenized ascomycetes) were examined using DNA sequences from the ITS1–5.8 S–ITS2 rDNA gene cluster and from the protein-coding β-tubulin gene. In addition to the fruticose species traditionally classified in Stereocaulon, representatives of the crustose species that have recently been transferred to the genus were included. Muhria, a monotypic genus that is morphologically similar to Stereocaulon, differing only in apothecia ontogeny, was also incorporated. The analyses included 101 specimens from the ingroup representing 49 taxa. Sequences from both DNA regions were analysed simultaneously using direct optimization under the parsimony optimality criterion. The results support the inclusion of the crustose species and Muhria in Stereocaulon, while the current infrageneric classification is not supported. As Muhria is securely nested within Stereocaulon the new combination Stereocaulon urceolatum comb. nov. (syn. Muhria urceolata) is made. Further, species concepts need to be re-examined, as some species do not appear as monophyletic entities in the phylogeny.  相似文献   

18.
梭菌属分类研究进展:现状和展望   总被引:2,自引:0,他引:2  
目前构成梭菌属的微生物在系统发育和表型特征上不一致。多相分类数据表明,梭菌属物种之间差异大。大量基于16S rRNA 基因的系统发育研究表明,梭菌属应被限定为梭菌属类群I,作为狭义梭菌属(Clostridium sensu stricto)。尽管有这方面认识,梭菌属新物种仍持续增加,这些新物种并不能与梭菌属类群I 和标准种丁酸梭菌(C. butryicum)形成一致分支,引发梭菌属分类上的混乱。本文明确了梭菌属物种的范围,即只包括模式种和梭菌属类群I。此外,4 个物种念珠状真杆菌(Eubacterium moniliforme)、旋舞真杆菌(Eubacterium tarantellae)、最大八叠球菌(Sarcina maxima)和胃八叠球菌(Sarcina ventriculi)应被调至梭菌属,分别命名为念珠状梭菌(Clostridium moniliforme)、旋舞梭菌(Clostridium tarantellae)、最大梭菌(Clostridium maximum)和胃梭菌(Clostridium ventriculi)。一个新属哈撒韦氏菌属(Hathewaya)被提议成立,3 个梭菌属物种溶组织梭菌(Clostridium histolyticum)、泥渣梭菌(Clostridium limosum)和解朊梭菌(Clostridiumproteolyticum)重新归为溶组织哈撒韦氏菌(Hathewaya histolytica)、泥渣哈撒韦氏菌(Hathewaya limosa)和解朊哈撒韦氏菌(Hathewaya proteolytica),其中Hathewaya histolytica 为模式种。  相似文献   

19.
Morphological and RAPD markers were used to assess the relationships among nodulating and non-nodulating species of AfricanAcacia. Non-nodulating species of AfricanAcacia are only found within subg.Aculeiferum sect.Monacanthea. African species of sect.Monacanthea examined were found to form a group distinct from the other African species examined on a morphological and molecular basis. All lack the ability to nodulate, suggesting that non-nodulation may be used as a taxonomic tool. The species of sect.Aculeiferum were separated by RAPD and morphological analysis into two groups depending on whether they were armed with prickles in pairs and/or prickles in threes, or solitary. A third group of species was identified within sect.Acacia: further subdivision of this group was achieved into subsectt.Pluriseriae andUniseriae. The position ofA. albida relative to other AfricanAcacia species was found to be distinct but not totally independent of the genus. The partitioning and distribution of the genetic variability within the genus is further elucidated by the RAPD analysis of populations ofAcacia species. A population analysis ofA. polyacantha demonstrated geographical and site-specific variation.  相似文献   

20.
Two new species of the coelomycete genusXenidiocercus are described and illustrated,X. macrospora on leaves ofMacaranga rowlandii andX. pyriformis on leaves ofM. huraefolia. They differ from the type species in having wider and ellipsoidal or pyriform conidia. A key to species ofXenidiocercus andIdiocercus is provided.  相似文献   

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