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1.
The genus Lambertella is currently considered to be one of the largest genera in the family Rutstroemiaceae, and its major distinguishing character is the pigmentation of ascospores, besides a substratal stroma. Although Lambertella appears to be well-defined by morphological characters, its phylogenetic heterogeneity has been suggested in earlier studies. To circumscribe the genus more precisely, morphological examination and phylogenetic analysis was conducted on some Lambertella species and some allied stroma-forming fungi. In total, 58 taxa were included in the study, including 16 species with both a substratal stroma and pigmented ascospores. The polyphyly of Lambertella sensu lato was confirmed based on the phylogenetic analysis of ITS, LSU, and RPB2 regions. A highly supported clade is composed of five Lambertella species, including the type L. corni-maris. Morphologically, all species here included in Lambertella s. s. have brown ascospores prior to being discharged from asci, whereas in other species currently placed in Lambertella, but now excluded from the genus, they turn brown only after discharge. This clade was defined as Lambertella sensu stricto. Pigmentation of the ascospores was also recognized in Lanzia and Poculum, and even in the helotiaceous genus Hymenoscyphus, but always only after discharge. The convergent evolution of a dark substratal stroma in Rutstroemiaceae and Helotiaceae was also indicated.  相似文献   

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Ophiocordyceps unituberculata, a new insect pathogenic fungus from southwestern China, is described using molecular phylogenetic and morphological data. This fungus differs from other Ophiocordyceps species by its enormously long monophialidic conidiogenous cells and a large periclinal protuberance often growing near the apex of conidiogenous cells, single conidia (lanceolate to fusiform) embedded in mucous sheath, and much larger conidial dimensions. Four-locus (nrSSU, nrLSU, tef-1α and rpb1) and ITS data phylogenetic analyses show that O. unituberculata belongs to the Hirsutella nodulosa clade within the genus Ophiocordyceps of Ophiocordycipitaceae and is a separate clade from other allied species. Molecular phylogeny and morphology both strongly support the distinctiveness of this taxon. The interspecific relationships in the H. nodulosa clade are discussed.  相似文献   

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During a survey of fungicolous fungi, a novel taxon from the surface of stroma of an unidentified Xylaria species was collected. Phylogenetic analyses showed that this taxon clustered with Calcarisporium sp. and C. arbuscula isolates, but was resolved as a distinct species. A detailed morphological examination coupled with phylogenetic analysis indicated that the taxon represented a new species. Calcarisporium xylariicola sp. nov. is thus introduced. The new taxon is characterized by short conidiophores with swollen bases and less length/width ratio of conidia that distinguish it from other Calcarisporium species. Calcarisporium is presently placed in Hypocreales genera, incertae sedis genus. Species in the genus are largely fungicolous, or occasionally caulicolous or foliicolous, and have hyaline, erect, verticillate conidiophores and sympodial, polyblastic conidiation. A phylogenetic analysis of combined SSU, ITS, LSU, TEF and RPB2 sequence data from Calcarisporium species and other taxa in Hypocreales indicate that Calcarisporium is a distinct lineage from other families. Therefore, a new family, Calcarisporiaceae, in Hypocreales is introduced.  相似文献   

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Species in Plectosphaerella are well known as pathogens of several plant species causing fruit, root and collar rot and collapse. In an investigation of endophytic fungi associated with cucurbit plants in China, we isolated 77 strains belonging to the genus Plectosphaerella. To identify the isolated strains, we collected the type or reference strains of all currently accepted species in Plectosphaerella except P. oratosquillae and conducted a phylogenetic analysis. Phylogenetic analysis of the partial 28S rDNA sequences showed that all species in Plectosphaerella were located in one clade of Plectosphaerellaceae. Based on multi-locus phylogenetic analysis of the ITS, CaM, EF1, TUB and morphological characteristics, all species in Plectosphaerella were well separated. Three endophytic strains from stems of Cucurbita moschata, Citrullus lanatus and Cucumis melo from North China were assigned to a new species described as P. sinensis in this paper. The new species differs morphologically from other Plectosphaerella species by irregular chlamydospores, and the dimensions of phialides and conidia. The other endophytic strains from several cucurbit plants were identified as P. cucumerina.  相似文献   

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Orphanodendron is a taxonomically and geographically isolated South American genus of two species. When first described by Barneby and Grimes in 1990, the genus was placed in Leguminosae subfamily Caesalpinioideae, but that placement was doubted and the name Orphanodendron (Gr. orphanos, orphan + dendron, tree) was chosen to reflect the uncertain subfamilial relationship of the genus. In this study, nucleotide sequence data from five Orphanodendron specimens were added to 662 other, previously sampled, Leguminosae taxa representing all three currently recognized subfamilies (Caesalpinioideae, Mimosoideae and Papilionoideae) in a matK maximum parsimony analysis that resolved Orphanodendron as a member of the genistoid s.l. clade of subfamily Papilionoideae. Two additional Bayesian phylogenetic analyses with reduced taxon sampling of plastid (matK combined with trnL-F) and nuclear (ITS) loci strongly support the monophyly of Orphanodendron and unambiguously establish Orphanodendron as a member of the genistoid sensu lato clade. Although our plastid phylogenetic analysis finds relatively low support for a sister-group relationship with the African genus Camoensia, the nuclear-encoded ITS resolves Orphanodendron as sister to the Bowdichia clade with strong support and Camoensia as sister to other core genistoids. The phylogenetic resolution of Orphanodendron as a member of the genistoid s.l. legumes based on nuclear and plastid sequences will undoubtedly advance future evolutionary investigations of this Colombian endemic tropical tree genus.  相似文献   

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A new poroid wood-inhabiting fungal genus, Leifiporia, is proposed, based on morphological and molecular evidence, which is typified by L. rhizomorpha sp. nov. The genus is characterized by an annual growth habit, resupinate basidiocarps with white to cream pore surface, a dimitic hyphal system with generative hyphae bearing clamp connections and branching mostly at right angles, skeletal hyphae present in the subiculum only and distinctly thinner than generative hyphae, IKI–, CB–, and ellipsoid, hyaline, thin-walled, smooth, IKI–, CB– basidiospores. Sequences of ITS and LSU nrRNA gene regions of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony and Bayesian inference methods. The phylogenetic analysis based on molecular data of ITS + nLSU sequences showed that Leifiporia belonged to the core polyporoid clade and was closely related to Diplomitoporus overholtsii and Lopharia cinerascens, and then grouped with Pycnoporus and Trametes. Further investigation was obtained for more representative taxa in the Polyporaceae based on nLSU sequences, in which the results demonstrated that the genus Leifiporia formed a monophyletic lineage with a strong support (100 % BS, 100 % BP, 1.00 BPP). Both morphological and molecular evidence confirmed the placement of the new genus in the core polyporoid clade. In addition, a new combination, Leifiporia eucalypti, is proposed based on examination of its type material and phylogeny.  相似文献   

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A new species of Orbilia related to O. luteorubella is described mainly based on morphological characters of its asexual morph and molecular data. The sexual morph does not significantly differ from O. luteorubella, whereas the asexual morph obtained from its ascospore isolate resembles members of the non-predacious genus Dactylella, because it has fusiform phragmoconidia borne singly at the apex of conidiophores. Phylogenetic analysis showed that this strain clustered with a clade that included available strains of the O. luteorubella aggregate and was distant from all analysed Dactylella species. Within this clade, the new strain fell between species with filiform conidia and those of a Pseudotripoconidium anamorph. By combining morphological and phylogenetic analyses, we conclude that our isolate belongs to a new taxon. Pleomorphism of the new taxon is described and discussed.  相似文献   

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The phylogenetic affinities of the fern genus Aenigmopteris have been the subject of considerable disagreement, but until now, no molecular data were available from the genus. Based on the analysis of three chloroplast DNA regions (rbcL, rps16-matK, and trnL-F) we demonstrate that Aenigmopteris dubia (the type species of the genus) and A. elegans are closely related and deeply imbedded in Tectaria. The other three species of genus are morphologically very similar; we therefore transfer all five known species into Tectaria. Detailed morphological comparison further shows that previously proposed diagnostic characters of Aenigmopteris fall within the range of variation of a broadly circumscribed Tectaria.  相似文献   

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We describe a new cliff-dwelling species within Sonchus (Asteraceae): Sonchus boulosii and analyze its systematic position and evolutionary significance; in addition, we provide a key to the species of Sonchus in Morocco. Both morphological and ecological characteristics suggest a close relationship of S. boulosii with taxa of section Pustulati. However, ITS nrDNA and cpDNA matK markers indicate its uncertain position within the genus, but clear genetic differentiation from the remaining major clades. ITS phylogenetic trees show that likely evolutionary shifts to rocky habitat took place at least five times within genus Sonchus and that sect. Pustulati and S. boulosii clades have a clearly independent evolutionary origin. We postulate that the strong resemblance of S. boulosii to other rocky species reflects a phenomenon of homoplasy, probably driven by parallel evolutionary adaptations to the severe ecological constraints of its cliff face habitat. Therefore, a new section is also described, which includes S. boulosii as its sole representative: section Pulvinati. According to phylogenetic trees, the new clade may share its common ancestor with the clade comprising sections Maritimi and Arvenses, from which it is widely divergent in morphology and ecology, with the exception of Sonchus novae-zelandiae. However, the latter is a derived taxon, with high level of polyploidy unlike S. boulosii that shows 2n?=?18, basal chromosome number of the genus. Since sections Pulvinati and Pustulati seem to be quite old in Sonchus, we also hypothesize that some similarities, such as fruit morphology, may reflect the persistence of some primitive characteristics.  相似文献   

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Two species of the genus Galeopsis L., G. tetrahit L. and G. bifida Boenn. (family Lamiaceae), are problematic to distinguish often wrongly recognized, and treated by some taxonomists as a single species. Morphological diagnostical characters of these species are variable and partly overlap. Species independence of G. tetrahit and G. bifida was evaluated and their diagnostic characters verified using ISSR and RAPD markers. A total of 57 ISSR and 28 RAPD fragments were obtained providing distinct subdivision of the accessions examined into two groups. Analysis of molecular data using the neighbor-joining method showed that the accessions studied fell into two clades in the same way as demonstrated by the analysis of 20 morphological characters using single linkage method. These results suggest that G. tetrahit and G. bifida are distinct species. The morphological characters were found to be more variable compared to the molecular markers, although the combined of these characters provided differentiation of the species.  相似文献   

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Rinorea, the second most species-rich genus in the Violaceae, has been shown to be polyphyletic with four separate clades recovered in phylogenetic studies. Among these clades is the Rinorea crenata group, which is composed of three Neotropical species. This group has been shown in family- and genus-level molecular phylogenies to be resolved outside of a large clade representing Rinorea s.str. Based on phylogenetic, morphological, and anatomical evidence, Bribria, a new genus, is segregated from Rinorea s.str. and described, with new combinations made for its three species: Bribria apiculata, Bribria crenata, and Bribria oraria. In addition, two new sections in Rinorea s.str. are described to accommodate the remaining Neotropical species: Rinorea sect. Rinorea and Rinorea sect. Pubiflora, which correspond to Group IIa Rinorea and Group IIc Pubiflora, respectively, in W. H. A. Hekking’s monograph of Neotropical Rinorea.  相似文献   

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Combined morphological and molecular analyses are employed to characterise three species of Tergestia Stossich, 1899 (Digenea: Fellodistomidae) from fishes of Moreton Bay, Queensland, Australia. Tergestia clonacantha Manter, 1963 is reported here for the first time from the halfbeak (Beloniformes: Hemiramphidae) species Arrhamphus sclerolepis krefftii (Steindachner), Hyporhamphus australis (Steindachner), H. quoyi (Valenciennes) and H. regularis ardelio (Whitley). Two new species, both infecting trevally (Perciformes: Carangidae) species, are described: T. maryae n. sp. from Alepes apercna Grant and T. henryi n. sp. from Pantolabus radiatus (MacLeay). Complete ITS2 and partial 28S ribosomal DNA data were generated for each of the new taxa. The three species differ from each other by 47–58 base pairs (bp) in the ITS2 rDNA region. Phylogenetic analysis of 28S rDNA supports Tergestia as a reliable generic concept, with our analyses showing that some species of the genus form a well-supported clade to the exclusion of all other fellodistomids for which sequence data are available.  相似文献   

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Birch trees inhabiting the high-altitude Hyrcanian forest (the southern shores of the Caspian Sea of Iran and Azerbaijan) are classified in the EN (endangered) category of the International Union for Conservation of Nature (IUCN). Taxonomic status and phylogenetic relationship of Iranian populations, molecular taxonomy, and biogeography of the genus Betula in the world have been considered. Four remnant populations of Betula were selected from north and northwestern parts of Iran. The internal ITS and trnH-psbA intergenic spacer regions were sequenced. Based on the trnH-psbA and ITS, Iranian birch and white birch were placed in a clade, but based on trnH-psbA divided into two subclades. Phylogenetic trees based on ITS and trnH-psbA data did not completely support the morphological classification. Network analysis confirms a close relationship of B. pendula with B. platyphylla and B. papyrifera with B. humilis, and B. ermanii were in a group with the other tetraploid species of the subgenus Neurobetula. Divergence time analysis showed that about 75 Ma ago the Betula genus separated from the other genus of Betulaceae and then divided into two main clades in Oligocene. Our divergence analysis supports that two subgenera of Betulenta and Betulaster are the oldest subgenera in the genus Betula and they date back to Eocene. The ancestral reconstruction suggests that ancestors of the genus Betula originated from Southeast Asia.  相似文献   

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