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1.
Nodulosphaeria is a ubiquitous genus that comprises saprobic, endophytic and pathogenic species associated with a wide variety of substrates and has 64 species epithets listed in Index Fungorum. The classification of species in the genus has been a major challenge due to a lack of understanding of the importance of characters used to distinguish taxa, as well as the lack of reference strains. The present study clarifies the phylogenetic placement of the genus and related species, using fresh collections from Italy. Four Nodulosphaeria species are characterized based on multi-loci analyses of ITS, LSU, SSU, TEF and RPB2 sequence datasets. Phylogenetic analyses indicate that Nodulosphaeria species group within the family Phaeosphaeriaceae as a distinct genus. The sexual morphs of Nodulosphaeria hirta and N. spectabilis are described and illustrated using modern concepts. Two new Nodulosphaeria species are introduced. The phylogenetic relationships and taxonomy of the genus Nodulosphaeria are discussed, but further sampling with fresh collections, reference or ex-type strains and molecular data are needed to obtain a better and natural classification for the genus.  相似文献   

2.
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   

3.
Tubeufia was named for a sexual morph taxon. However, several asexual morph species have been accommodated in this genus as well. In our study, four new species of Tubeufia, viz. T. filiformis, T. latispora, T. laxispora and T. mackenziei, are described and illustrated. The phylogenetic placement of the new species is confirmed by analysis of combined ITS, LSU and TEF1α sequence data. A key to Tubeufia species is provided and the new species are compared with similar fungal taxa.  相似文献   

4.
A total of 204 specimens belonging to eight species of the genus Lemniscomys were examined with standard morphometric measurements. Our results show that the seven Sub-Saharan species seem to follow a latitudinal gradient from the Center to the South of the African continent. The only North African species L. barbarus looks close to L. griselda and L. rosalia. We also applied a molecular analysis through PCR (Polymerase Chain Reaction) method for the amplification of the 16S rRNA gene. For the purpose of constructing a phylogenetic tree with Maximum Likelihood method, we extracted eight sequences from the GenBank library; seven belonging to the genus Lemniscomys and one to the genus Arvicanthis used as outgroup. We managed to identify a region comprised of 458 nucleotides of which 388 were common for all species and 70 were variable. The phylogenetic tree shows us that the sister group L. bellieri and L. macculus, is the most basal, while L. striatus and L. rosalia appears to be close to the sister group L. barbarus and L. zebra. We also noticed a difference between morphometric and molecular results; the latter are more in agreement with pelage patterns subdivision between Lemniscomys species. These differences can be explained by a high rate of phenotypic evolution that can surpass the molecular counterpart as in the case of the genus Gerbillus.  相似文献   

5.
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   

6.
7.
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   

8.
Environmental sampling yielded two yeast species belonging to Microstromatales (Exobasidiomycetes, Ustilaginomycotina). The first species was collected from a leaf phylloplane infected by the rust fungus Coleosporium plumeriae, and represents a new species in the genus Jaminaea, for which the name Jaminaea rosea sp. nov. is proposed. The second species was isolated from air on 50% glucose media and is most similar to Microstroma phylloplanum. However, our phylogenetic analyses reveal that species currently placed in Microstroma are not monophyletic, and M. phylloplanum, M. juglandis and M. albiziae are not related to the type species of this genus, M. album. Thus, Pseudomicrostroma gen. nov. is proposed to accommodate the following species: P. glucosiphilum sp. nov., P. phylloplanum comb. nov. and P. juglandis comb. nov. We also propose Parajaminaea gen. nov. to accommodate P. albizii comb. nov. and P. phylloscopi sp. nov. based on phylogenetic analyses that show these are not congeneric with Jaminaea or Microstroma. In addition, we validate the genus Jaminaea, its respective species and two species of Sympodiomycopsis and provide a new combination, Microstroma bacarum comb. nov., for the anamorphic yeast Rhodotorula bacarum. Our results illustrate non-monophyly of Quambalariaceae and Microstromataceae as currently circumscribed. Taxonomy of Microstroma and the Microstromataceae is reviewed and discussed. Finally, analyses of all available small subunit rDNA sequences for Jaminaea species show that J. angkorensis is the only known species that possess a group I intron in this locus, once considered a potential feature indicating the basal placement of this genus in Microstromatales.  相似文献   

9.
Gloeoporus Mont. is characterized by an easily separated gelatinous hymenophore and a continuous hymenium over the pore mouth. Recent molecular taxonomic and phylogenetic research showed that morphological grouping of Gloeoporus is polyphyletic. The lack of comprehensive phylogenetic studies of Gloeoporus exacerbates confusion in determining the taxonomic position of the genus. To delimit the genus Gloeoporus, we performed multi-locus phylogenetic analysis using the internal transcribed spacer (ITS) region, the nuclear large subunit ribosomal DNA (LSU), and the second-largest subunit of RNA polymerase II (rpb2). The phylogenetic analyses revealed that current delimitation of Gloeoporus is not monophyletic. Gloeoporus s.s. includes mostly clamped species lacking cystidia. Some species of Gloeoporus featuring simple septa and cystidia are proposed to be renamed to Meruliopsis. Two new species of Gloeoporus were also observed and they are named Gloeoporus africanus and Gloeoporus orientalis.  相似文献   

10.
Geometric morphometric and phylogenetic analyses, applied to 43 species of Russelliana, shed light on the evolution of insect wing shape. Unconstrained and constrained ordination techniques are introduced to detect patterns of the forewing shape variation within genus. Results show a high congruence between forewing shape variation and host-plant preference supporting monophyly of most phylogenetic groups in Russelliana. Reconstruction of the ancestral forewing state shows its similarity to a forewing shape of Solanaceae feeding species defined as ancestors by the phylogenetic study supporting a hypothesis as to a primary association of Russelliana with Solanaceae. In contrast to some other comparative studies on insect wing shape, results of the present study reveal a strong correlation between variation of forewing shape in Russelliana and its phylogeny. Potential influence of vicariant events and host shifts on the evolution of forewing shape is discussed.  相似文献   

11.
Rare pathogens on unusual hosts are often providing valuable insight into the evolution of the pathogen group concerned, but it is often challenging to obtain sequence data for these, as because only very few, often decades-old specimens are available. One such example is Albugo tropica, the white blister pathogen of a basal angiosperm in the genus Peperomia (Piperaceae). For this species, only two, more than 70 and over 120-year-old collections available. Here, sequence data for A. tropica are reported and phylogenetic reconstructions reveal it as the sister group to all other white blister rusts of the genus Albugo. Its isolated position is also reflected by several morphological differences to the other species of the genus, such as very thin-walled sporangia and almost smooth oospores. The isolated phylogenetic position of the pathogen and its host might indicate that it is a relict species trapped on its host. The sister-group relationship to all members of the genus Albugo s.str., which have been investigated using molecular phylogenetics, hints at the possibility, that Albugo might have originated in South America or Gondwana and has later radiated in the holarctic on members of the Brassicales.  相似文献   

12.
Pseudo-nitzschia is a thoroughly studied pennate diatom genus for ecological and biological reasons. Many species in this genus, including Pseudo-nitzschia multistriata, can produce domoic acid, a toxin responsible for amnesic shellfish poisoning. Physiological, phylogenetic and biological features of P. multistriata were studied extensively in the past. Life cycle stages, including the sexual phase, fundamental in diatoms to restore the maximum cell size and avoid miniaturization to death, have been well described for this species. P. multistriata is heterothallic; sexual reproduction is induced when strains of opposite mating type are mixed, and proceeds with cells producing two functionally anisogamous gametes each; however, detailed cytological information for this process is missing. By means of confocal laser scanning microscopy and nuclear staining, we followed the nuclear fate during meiosis, and using time-lapse cinematography, we timed every step of the sexual reproduction process from mate pairing to initial cell hatching. The present paper depicts cytological aspects during gametogenesis in P. multistriata, shedding light on the chloroplast behaviour during sexual reproduction, finely describing the timing of the sexual phases and providing reference data for further studies on the molecular control of this fundamental process.  相似文献   

13.
The genus Otidea was recently monographed and studied phylogenetically, but knowledge of the diversity and distribution of Otidea species in China is fragmentary. In this study, collections from China were examined morphologically and included in phylogenetic analyses. Using LSU, TEF1-α, and RPB2 new species were placed within previously recognized clades in the genus. The results agree with both Genealogical Concordance Phylogenetic Species Recognition (GCPSR) and genetic divergence as previously reported. Three new species, Otidea hanseniae, Otidea korfii and Otidea purpureogrisea are recognized based on phylogenetic reconstruction using ITS, LSU, TEF1- α and RPB2. Comments on some incompletely known species are added. With the discovery of these three new species, the genus Otidea in China proves to be more diverse than previously recognized.  相似文献   

14.
This study reflects on the monophyly of, and species diversity within, the genus Pseudocercospora in Far East Asia. Morphological characteristics and phylogenetic analyses of Pseudocercospora species were based on type specimens and ex-type cultures, which were collected from Japan and Taiwan. A phylogenetic tree was generated from multi-locus DNA sequence data of the internal transcribed spacer regions of the nrDNA cistron (ITS), partial actin (actA), and partial translation elongation factor 1-alpha (tef1), as well as the partial DNA-directed RNA polymerase II second largest subunit (rpb2). Based on these results, Pseudocercospora amelanchieris on Amelanchier and Ps. iwakiensis on Ilex were newly described from Japan, and a further 22 types (incl. two neo-, five lecto-, and 15 epitypes), were designated. The genus Pseudocercospora as presently circumscribed was found to be monophyletic, while the secondary barcodes, actA, tef1, and rpb2 were shown to be well suited to delimitate species within the genus.  相似文献   

15.
16.
The study of how climatic niches change over evolutionary time has recently attracted the interest of many researchers. Different methodologies have been employed principally to analyze the temporal dynamics of the niche and specially to test for the presence of phylogenetic niche conservatism. Menonvillea, a genus of Brassicaceae including 24 species, is distributed primarily along the Andes of Argentina and Chile, with some taxa growing in southern Patagonia and others in the Atacama Desert and the Chilean Matorral. The genus is highly diversified morphologically but also presents a remarkably wide ecological range, growing from the high Andean elevations, to the dry coastal deserts in Chile, or the Patagonia Steppe in Argentina. In this study, we used molecular phylogenies together with climatic data to study climatic niche evolution in the genus. The results show that the main climatic niche shifts in Menonvillea occurred between the sections Cuneata-Scapigera and sect. Menonvillea throughout the Mid-Late Miocene, and associated with the two main geographical distribution centers of the genus: the highlands of the central-southern Andes and the Atacama Desert-Chilean Matorral, respectively. Climatic niches in these lineages were mainly differentiated by the aridity and potential evapotranspiration, the minimum temperatures of the coldest month, and the temperature annual range and seasonality. Niche evolution in Menonvillea deviated from a Brownian motion process, with most of the climatic dimension best-fitting to an Ornstein-Uhlenbeck model of multiple adaptive peaks. Our results also indicated that higher aridity levels and lower annual temperature ranges were associated with the evolution of the annual habit, as exemplified by the distribution of sect. Menonvillea. Finally, the results suggested that climatic niche evolution in Menonvillea exhibited some degree of phylogenetic niche conservatism, fundamentally within the two main lineages (sect. Menonvillea and sects. Cuneata-Scapigera).  相似文献   

17.
18.
The diversity of rhizobia that establish symbiosis with Lotus corniculatus has scarcely been studied. Several species of Mesorhizobium are endosymbionts of this legume, including Mesorhizobium loti, the type species of this genus. We analysed the genetic diversity of strains nodulating Lotus corniculatus in Northwest Spain and ten different RAPD patterns were identified among 22 isolates. The phylogenetic analysis of the 16S rRNA gene showed that the isolated strains belong to four divergent phylogenetic groups within the genus Mesorhizobium. These phylogenetic groups are widely distributed worldwide and the strains nodulate L. corniculatus in several countries of Europe, America and Asia. Three of the groups include the currently described Mesorhizobium species M. loti, M. erdmanii and M. jarvisii which are L. corniculatus endosymbionts. An analysis of the recA and atpD genes showed that our strains belong to several clusters, one of them very closely related to M. jarvisii and the remanining ones phylogenetically divergent from all currently described Mesorhizobium species. Some of these clusters include L. corniculatus nodulating strains isolated in Europe, America and Asia, although the recA and atpD genes have been sequenced in only a few L. corniculatus endosymbionts. The results of this study revealed great phylogenetic diversity of strains nodulating L. corniculatus, allowing us to predict that even more diversity will be discovered as further ecosystems are investigated.  相似文献   

19.
Mucuna comprises 105 species with an overall pantropical distribution and is divided into three subgenera: M. subg. Mucuna, M. subg. Stizolobium and M. subg. Macrocarpa. Although phylogenetic studies have supported the occurrence of three main clades, evolutionary relationships among them are not fully resolved. The objective of this study was to examine pollen grain morphology from representatives of all three subgenera and map these onto the phylogenetic trees generated by analysis of other characters. Pollen grain surface, form, size, and aperture number were compared. A Bayesian inference tree using matK sequences was constructed. The results indicate that the representatives of M. subg. Macrocarpa have the smallest pollen grains in the genus (a synapomorphic character here identified for this subgenus) and that species of subgenus Mucuna (those with umbelliform inflorescences) have the largest pollen grains. Additional morphological diversity of the pollen grain surface was noted: reticulate and/or micro-reticulate (in all three subgenera), perforate, gemmate or verrucose (only in M. subg. Mucuna). For all studied taxa, the pollen grains are triaperturate, except for two species of M. subg. Mucuna, which have tetraperturate pollen. The phylogenetic tree obtained using the matK marker resolved M. subg. Stizolobium as the earliest diverging lineage in Mucuna. Based on this phylogeny, a reticulate ornamentation pattern of the pollen surface may represent the ancestral state for the genus, while the larger pollen size and the foraminate, gemmate, and verrucose ornamentations are derived characteristics within the genus. These putative derived ornamentations have been observed only in neotropical species.  相似文献   

20.
The nucleotide sequences of the nuclear rDNA ITS regions were determined for 34 species of the genus Primula L. and one species of the genus Cortusa L., family Primulaceae Vent., and used to infer the phylogenetic relationships among these species. In this analysis species of the Russian flora and the flora of adjacent territories were studied for the first time. The results clarified the taxomic structure of the genus Primula and confirmed the entity of some of its sections; but not the subgenera sensu J.Richards. Our data do not support an independent status of the genus Cortusa, placing it as one of the terminal lineages of the section Cortusoides Balf. f. in the genus Primula.  相似文献   

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