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1.
Phylogenetic relationships of lichen-forming discomycetes and their relatives in the class Lecanoromycetes were examined by using nuclear large subunit and mitochondrial small subunit ribosomal DNA sequences. Ninety-eight partial sequences of 53 ascomycetes were generated and aligned with the corresponding sequences retrieved from GenBank resulting in an alignment of 100 taxa that was analyzed using a Bayesian approach with Markov chain Monte Carlo (B/MCMC) methods. The analysis revealed the monophyly of the Lecanoromycetes with two major clades: one clade including the monophyletic orders Graphidales and Ostropales and the paraphyletic Gyalectales, the other clade including the monophyletic Lecanorales (incl. Caliciales, Peltigerales, and Teloschistales) and a clade containing the polyphyletic Agyriales, a yet undescribed order Umbilicariales (including Elixiaceae and Umbilicariaceae), and Pertusariales. The monophyly of the Pertusariales was not resolved. Testing of alternative hypotheses revealed that a placement of Chaetothyriomycetes and Eurotiomycetes within Lecanoromycetes and the monophyly of Agyriales s. lat. (incl. Elixiaceae and Schaereriaceae) and Ostropales s. lat. (incl. Graphidales) can be rejected, while monophyly of Gyalectales and the Pertusariales and placement of Umbilicariales on the Lecanorales branch cannot be rejected with the current data set.  相似文献   

2.
The phylogeny and systematic position of Gomphillaceae was reconstructed using a combined Bayesian analysis of nuclear LSU rDNA and mitochondrial SSU rDNA sequences. Twenty-four partial sequences of 12 taxa (11 Gomphillaceae and one Asterothyriaceae) plus two new sequences of Stictis radiata (Ostropales outgroup) were generated and aligned with the corresponding sequences retrieved from GenBank, resulting in an alignment of 82 taxa that was analyzed using a Bayesian approach with Markov chain Monte Carlo (B/MCMC) methods. Our results confirm Gomphillaceae sensu Vezda and Poelt plus Asterothyriaceae to be a monophyletic group, with an unresolved relationship between the two families. Placement of Gomphillaceae and Asterothyriaceae within Ostropales sensu Kauff and Lutzoni, as sister of Thelotremataceae, also is strongly supported. Alternative hypotheses placing Gomphillaceae in Lecanorales (Cladoniaceae), Agyriales (Baeomycetaceae) or within bitunicate Ascomycota (Arthoniomycetes, Chaetothyriomycetes, Dothideomycetes) were rejected with our dataset. After recent synonymization of Dimerella with Coenogonium (Ostropales: Coenogoniaceae), we propose the new combination Coenogonium pineti (one of our Ostropales outgroup taxa in this analysis).  相似文献   

3.
4.
Fossil taxa are critical to inferences of historical diversity and the origins of modern biodiversity, but realizing their evolutionary significance is contingent on restoring fossil species to their correct position within the tree of life. For most fossil species, morphology is the only source of data for phylogenetic inference; this has traditionally been analysed using parsimony, the predominance of which is currently challenged by the development of probabilistic models that achieve greater phylogenetic accuracy. Here, based on simulated and empirical datasets, we explore the relative efficacy of competing phylogenetic methods in terms of clade support. We characterize clade support using bootstrapping for parsimony and Maximum Likelihood, and intrinsic Bayesian posterior probabilities, collapsing branches that exhibit less than 50% support. Ignoring node support, Bayesian inference is the most accurate method in estimating the tree used to simulate the data. After assessing clade support, Bayesian and Maximum Likelihood exhibit comparable levels of accuracy, and parsimony remains the least accurate method. However, Maximum Likelihood is less precise than Bayesian phylogeny estimation, and Bayesian inference recaptures more correct nodes with higher support compared to all other methods, including Maximum Likelihood. We assess the effects of these findings on empirical phylogenies. Our results indicate probabilistic methods should be favoured over parsimony.  相似文献   

5.
The monotypic, lichen-forming genus Ingvariella originally was segregated from Diploschistes and placed within the Thelotremataceae (Ostropales) based on aspects of exciple morphology. However, the I+ hymenium and amyloid ascus wall suggest affinities to families other than the Thelotremataceae. To assess the identity of Ingvariella and to investigate its placement within the Ostropales, we inferred phylogenetic relationships of I. bispora by comparison of mtSSU rDNA and nuLSU rDNA sequences for 59 species encompassing a broad array of ostropalean fungi by means of Bayesian, maximum likelihood and weighted maximum parsimony methods. Here we report that Ingvariella is a member of the Stictidaceae, sister to the mainly saprotrophic genus Cryptodiscus. The inclusion of the first saxicolous lichen-forming fungus within this family expands the broad ecological diversity of the Stictidaceae, where saprotrophic fungi, corticicolous lichen-forming fungi and lichenized and non-lichenized conspecific taxa have been described previously. We also present new insights into the relationships among other families within the Ostropales.  相似文献   

6.
绒衣属(Coenogonium)地衣属于真菌界(Fungi)子囊菌门(Ascomycota)茶渍纲(Lecanoromycetes)厚顶盘亚纲(Ostropomycetidae)厚顶盘目(Ostropales)绒衣科(Coenogoniaceae),主要分布于热带和亚热带地区。综述了绒衣属地衣研究简史和中国研究概况;报道了中国该属10种地衣,其中1种为中国新记录种:疏羽绒衣(Coenogonium disjunctum)。对各种进行了描述和讨论,并给出了中国绒衣属的检索表和新记录种的图片。这是首次对中国绒衣属地衣的系统研究,为地衣型真菌分类学研究提供了基础资料。  相似文献   

7.
Within the last decade, molecular methods have revealed the relationships in many groups of lichenized Ascomycetes. However, the published phylogenies were often contradictory with respect to higher taxonomic levels. To achieve a more convincing overall picture of phylogenetic relationships of and within the Lecanoromycetes, we set up an alignment of all publicly available SSU nrDNA sequences of the Pezizomycotina, discarded those of insufficient quality, and added 21 newly obtained sequences representing groups that were not or under-represented so far. The alignment of 635 taxa and a subset of 166 Lecanoromycetes were analysed with different phylogenetic algorithms. The best phylogenetic trees, with respect to length, resolution, and support, were obtained with the Parsimony Ratchet method and DNAPARS (Phylip). According to these results, the Lecanoromycetes were subdivided into eight monophyletic clades representing the following orders: Acarosporales ad. int., Agyriales, Baeomycetales, Gyalectales, Icmadophilales ad. int., Lecanorales, Ostropales, and Pertusariales. These clades are distributed in two monophyletic groups corresponding to the two different types of ascomatal ontogeny. The taxa of the Lecanorales-clade differ from the other orders by the absence of a primary cyanobiont and of phycobionts of the genera Coccomyxa and Trentepohlia, in combination with the presence of an amyloid reaction of the ascus tips (lacking amyloid flanks). The Lecanorales-clade is subdivided into nine groups which are treated here at the level of suborders: Lecideineae, Teloschistineae, Physciineae, Bacidiineae ad int., Sphaerophorineae ad int., Rhizocarpineae ad int., Psorineae ad int., Cladoniineae, and Lecanorineae. The amyloid reaction pattern of the ascus apex correlates with this grouping at suborder rank. Peltigerales were excluded from the Lecanorales but included in the Lecanoromycetes based on morpho-anatomical features. The Lichinales were excluded from the Lecanoromycetes, while the position of the Umbilicariaceae remains unclear.  相似文献   

8.
Arctic tundra regions have been responding to global warming with visible changes in plant community composition, including expansion of shrubs and declines in lichens and bryophytes. Even though it is well known that the majority of arctic plants are associated with their symbiotic fungi, how fungal community composition will be different with climate warming remains largely unknown. In this study, we addressed the effects of long‐term (18 years) experimental warming on the community composition and taxonomic richness of soil ascomycetes in dry and moist tundra types. Using deep Ion Torrent sequencing, we quantified how OTU assemblage and richness of different orders of Ascomycota changed in response to summer warming. Experimental warming significantly altered ascomycete communities with stronger responses observed in the moist tundra compared with dry tundra. The proportion of several lichenized and moss‐associated fungi decreased with warming, while the proportion of several plant and insect pathogens and saprotrophic species was higher in the warming treatment. The observed alterations in both taxonomic and ecological groups of ascomycetes are discussed in relation to previously reported warming‐induced shifts in arctic plant communities, including decline in lichens and bryophytes and increase in coverage and biomass of shrubs.  相似文献   

9.
The evolutionary history of gains and losses of vegetative reproductive propagules (soredia) in Porpidia s.l., a group of lichen-forming ascomycetes, was clarified using Bayesian Markov chain Monte Carlo (MCMC) approaches to monophyly tests and a combined MCMC and maximum likelihood approach to ancestral character state reconstructions. The MCMC framework provided confidence estimates for the reconstructions of relationships and ancestral character states, which formed the basis for tests of evolutionary hypotheses. Monophyly tests rejected all hypotheses that predicted any clustering of reproductive modes in extant taxa. In addition, a nearest-neighbor statistic could not reject the hypothesis that the vegetative reproductive mode is randomly distributed throughout the group. These results show that transitions between presence and absence of the vegetative reproductive mode within Porpidia s.l. occurred several times and independently of each other. Likelihood reconstructions of ancestral character states at selected nodes suggest that--contrary to previous thought--the ancestor to Porpidia s.l. already possessed the vegetative reproductive mode. Furthermore, transition rates are reconstructed asymmetrically with the vegetative reproductive mode being gained at a much lower rate than it is lost. A cautious note has to be added, because a simulation study showed that the ancestral character state reconstructions were highly dependent on taxon sampling. However, our central conclusions, particularly the higher rate of change from vegetative reproductive mode present to absent than vice versa within Porpidia s.l., were found to be broadly independent of taxon sampling.  相似文献   

10.
The phylogenetic relationships within the subclass of Elasmobranchii are under question within the academic community and their systematic classification based on morphological, or physiological characteristics has not yet been fully justified. Modern cladistic studies suggested that batoids are derived sharks, a taxonomic status known as the Hypnosqualean hypothesis. The main purpose of this study was to address this issue using a data set of aligned, directly sequenced, mitochondrial cytochrome oxidase subunits I and II. Maximum Likelihood, Maximum Parsimony, Minimum Evolution and Bayesian inference were implemented for tree reconstructions. The results provided evidence that supported the rejection of the above hypothesis, in accordance with other recent molecular phylogenetic studies. More specifically Rajiformes species were presented as separate lineages from sharks. Prionace species on the other hand was grouped within Carcharhinoformes, which was clustered as sister group to Lamniformes. COI and COII regions supported, monophylies of Squaliformes and paraphylies of Carchariniformes.  相似文献   

11.
Establishing the dates for the origin and main diversification events in the phylogeny of Ascomycota is among the most crucial remaining goals in understanding the evolution of Fungi. There have been several analyses of divergence times in the fungal tree of life in the last two decades, but most have yielded contrasting results for the origin of the major lineages. Moreover, very few studies have provided temporal estimates for a large set of clades within Ascomycota. We performed molecular dating to estimate the divergence times of most of the major groups of Ascomycota. To account for paleontological uncertainty, we included alternative fossil constraints as different scenarios to enable a discussion of the effect of selection of fossils. We used data from 6 molecular markers and 121 extant taxa within Ascomycota. Our various ‘relaxed clock’ scenarios suggest that the origin and diversification of the Pezizomycotina occurred in the Cambrian. The main lineages of lichen–forming Ascomycota originated at least as early as the Carboniferous, with successive radiations in the Jurassic and Cretaceous generating the diversity of the main modern groups. Our study provides new information about the timing of the main diversification events in Ascomycota, including estimates for classes, orders and families of both lichenized and non–lichenized Ascomycota, many of which had not been previously dated.  相似文献   

12.
13.
Sugiyama J  Hosaka K  Suh SO 《Mycologia》2006,98(6):996-1005
The early diverging Ascomycota lineage, detected primarily from nSSU rDNA sequence-based phylogenetic analyses, includes enigmatic key taxa important to an understanding of the phylogeny and evolution of higher fungi. At the moment six representative genera of early diverging ascomycetes (i.e. Taphrina, Protomyces, Saitoella, Schizosaccharomyces, Pneumocystis and Neolecta) have been assigned to "Archiascomycetes" sensu Nishida and Sugi ama (1994) or the subphylum "Taphrinomycotina" sensu Eriksson and Winka (1997). The group includes fungi that are ecologically and morphologically diverse, and it is difficult therefore to define the group based on common phenotypic characters. Bayesian analyses of nSSU rDNA or combined nSSU and nLSU rDNA sequences supported previously published Ascomycota frameworks that consist of three major lineages (i.e. a group of early diverging Ascomycota. [Taphrinomycotina], Saccharomycotina and Pezizomycotina); Taphrinomycotina is the sister group of Saccharomycotina and Pezizomycotina. The 50% majority rule consensus of 18000 Bayesian MCMCMC-generated trees from multilocus gene sequences of nSSU rDNA, nLSU rDNA (D1/D2), RPB2 and beta-tubulin also showed the monophyly of the three subphyla and the basal position of Taphrinomycotina in Ascomycota with significantly higher statistical support. However to answer controversial questions on the origin, monophyly and evolution of the Taphrinomycotina, additional integrated phylogenetic analyses might be necessary using sequences of more genes with broader taxon sampling from the early diverging Ascomycota.  相似文献   

14.
陈乐雯  贾泽峰 《广西植物》2023,43(10):1784-1792
星文衣属(Sarcographa)隶属于真菌界(Fungi)、子囊菌门(Ascomycota)、茶渍纲(Lecanoromycetes)、厚顶盘目(Ostropales)、文字衣科(Graphidaceae),该属地衣体为壳状,子囊盘为放射分支状,多具子座,子囊含8孢子,子囊孢子褐色,横隔透镜型或亚砖壁型,主要分布于热带亚热带地区。该文通过形态学、解剖学、化学与分子生物学等方法进行该属分类学研究,共报道了中国该属9种,其中变黄星文衣[Sarcographa flavescens(Dal-Forno & Eliasaro)L. W. Chen & Z. F. Jia]为新组合(≡ Phaeographis flavescens Dal-Forno & Eliasaro); 曲线星文衣[Sarcographa labyrinthica (Ach.)Müll. Arg. ]为中国大陆新记录种。同时,该文对近似属拟星文衣属(Sarcographina)的1物种——异孢拟星文衣[Sarcographina heterospora(Nyl.)Z. F. Jia & Lücking]进行了描述,并提供了10个物种的特征提要及与其近似种的区别特征,并编制了分种检索表。该研究为中国地衣型真菌生物多样性研究提供了基础资料。  相似文献   

15.
Calicioid or mazaediate fungi constitute a heterogeneous assemblage of fungi sharing the presence of a mazaedium. These fungi were once treated as an order (Caliciales) of the Ascomycota but many are now known to be nested within the Arthoniomycetes, Eurotiomycetes, Lecanoromycetes and Leotiomycetes. In this study we employ multigene phylogenetic analyses of main mazaediate groups (based on nuclear 18S, 28S, 5.8S rDNA, mitochondrial 16S, and the protein coding RPB1 and Mcm7) of 116 taxa corresponding to most major groups of the inoperculate ascomycetes (“Leotiomyceta”) and a selection of Pezizomycetes, to trace the evolution of the mazaedium in the Pezizomycotina (the “Euascomycetes”). In particular, we studied the placement of three calicioid groups of uncertain position, Calycidiaceae, Coniocybaceae and Microcaliciaceae. Here, we show that the Calycidiaceae is closely related to the Sphaerophoraceae in the Lecanoromycetidae (Lecanoromycetes), as supported by overall morphology and the production of sphaerophorin. The Coniocybaceae constitute an early divergent line in the inoperculate ascomycetes and here we propose to recognize this group formally as the new class and order Coniocybomycetes, Coniocybales. The Microcaliciaceae is nested within the Ostropomycetidae (Lecanoromycetes). Both Coniocybaceae and Microcaliciaceae, although highly distinctive, lack morphological similarities to related main fungal groups. Ancestral state reconstruction suggests that the ancestor of all inoperculate ascomycetes and the ancestor of all main inoperculate ascomycete groups, with the exception of the Coniocybomycetes, was non‐mazediate, and thus confirms the large amount of parallel evolution and independent gains of the mazaedium in the history of the Ascomycota.  相似文献   

16.
The catalogue is based on a comprehensive evaluation of 152 published sources. It includes 624 species (with 4 subspecies and 13 varieties) of lichenized and 17 species of lichenicolous Ascomycota, as well as 9 non-lichenized Ascomycota traditionally included in lichenological literature.  相似文献   

17.
18.
Abstract: The Lichinales are a group of lichenized ascomycetes that almost exclusively possess cyanobacteria as their primary photobiont and are hitherto separated from the Lecanorales, the major group of lichenized ascomycetes, by thallus structure, ascoma ontogeny, ascus structure and ascus function. The relationship of the two families Peltulaceae and Lichinaceae, both placed within the Lichinales, with the Heppiaceae, placed within the Lecanorales, was investigated, as well as a possible sister group relationship of the Lichinales to the Lecanorales. Phylogenetic analyses included non-molecular data as well as 18S rDNA sequence data. The monophyly of the Lichinales including the family Heppiaceae and a sister group relationship of Lichinales and Lecanorales, based on the shared presence of lecanoralean asci, are proposed in a morphological hypothesis. Parsimony and distance analyses of 18S rDNA sequence data strongly support the monophyly of the Lichinales, including all three families. Therefore, the presence of rostrate, lecanoralean asci in Peltula and part of the Lichinaceae suggests that this ascus type is an autapomorphy of the monophyletic Lichinales. Furthermore, the occurrence of prototunicate asci in the Heppiaceae and most of the Lichinaceae is autapomorphic and was gained independently by reduction of the rostrate ascus. The 18S rDNA analysis did not reject the non-molecular hypothesis of a sister group relationship of the Lichinales and the Lecanorales as based on ascus characters. The alternative placement of the Lichinales as the sister group of all inoperculate euascomycetes excluding the Sordariomycetes and most of the Leotiales in the gene tree received unsufficient bootstrap support and no support from any non-molecular data and consequently was rejected.  相似文献   

19.
Phylogenetic relationships of 6 species in the trematode subfamily Haplorchiinae were analyzed using small and large subunit of ribosomal DNA genes (18S rDNA and 28S rDNA) and internal transcribed spacer subunit II (ITS2) region as molecular markers. Maximum Likelihood and Bayesian inference analyses of combined rDNAs and ITS2 indicated a close relationship between the genera Haplorchis and Procerovum, while these two genera were distinct from Stellantchasmus falcatus. These phylogenetic relationships were consistent with the number of testes but not with the characters of the modification of the seminal vesicle or of the ventral sucker. Although three Haplorchis spp. were, together with Procerovum, in the same cluster, their mutual topology was incongruent between rDNA and ITS2 trees. Phylogenetic analyses using other molecular markers with more species are necessary to work out solid phylogenetic relationships among the species in this subfamily.  相似文献   

20.
We provide the first molecular phylogeny of the clerid lineage (Coleoptera: Cleridae, Thanerocleridae) within the superfamily Cleroidea to examine the two most recently proposed hypotheses of higher level classification. Phylogenetic relationships of checkered beetles were inferred from approximately ~5000 nt of both nuclear and mitochondrial rDNA (28S, 16S and 12S) and the mitochondrial protein‐coding gene COI. A worldwide sample of ~70 genera representing almost a quarter of generic diversity of the clerid lineage was included and phylogenies were reconstructed using Bayesian and Maximum Likelihood approaches. Results support the monophyly of many proposed subfamilies but were not entirely congruent with either current classification system. The subfamilial relationships within the Cleridae are resolved with support for three main lineages. Tillinae are supported as the sister group to all other subfamilies within the Cleridae, whereas Thaneroclerinae, Korynetinae and a new subfamily formally described here, Epiclininae subf.n ., form a sister group to Clerinae + Hydnocerinae.  相似文献   

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