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1.
The members of Mycena sect. Calodontes (Tricholomataceae s.l., Basidiomycota) are characterised by a collybioid aspect and more or less purplish to reddish colours and a distinct raphanoid odour. In Europe, nine species have been recognised though some of these based on somewhat dubious morphological differences. Historically, most were assigned to Mycena pura. However, since Mycena pura displays one of the most striking colour variabilities within European agarics, many attempts have been made to subdivide it into independent entities, and several forms, varieties and species have been split from Mycena pura s.l. based largely on differences in colouration, gross macromorphology or other phenetic traits. We developed a large sample of ITS sequences of all species of sect. Calodontes known from Europe for which vouchers exist. Furthermore, partial LSU data were developed and additional sequences downloaded from GENBANK to assess the relationship of Calodontes with other Mycena spp. We show that most Calodontes form a monophyletic group including a few North and South American collections, but that this cannot be conclusively shown when an additional North American sequence is added. For all other species than M. pura and M. diosma, we found morphological species recognition to be in agreement with the ITS data. Several significantly different clades can be recognised within the M. pura morphospecies, none of which can be linked to the observed (and described by proxy) colour varieties/forms. Indications of a possible environmental basis of the colour differentiation in the M. pura morphospecies are discussed.  相似文献   

2.
The genetic diversity of two agaricoid saprotroph genera, Galerina and Mycena, and their distribution across bryophyte host species, and within bryophytes' photosynthetic and senescent tissues, was assessed using data from two pyrosequencing biodiversity inventories of bryophilous fungi. A total of 9 498 Galerina and 5 731 Mycena reads were mapped to branches broadly distributed throughout backbone trees, reflecting no obvious evolutionary specialization of particular fungal lineages to moss hosts/substrata. Although a few OTUs occurred with equal frequency across the hosts, most exhibited some degree of specialization to one or more bryophytes, indicating that the quality of different mosses as substratum varies between species. With one exception, all Galerina and Mycena OTUs were more frequent and abundant in senescent than photosynthetic tissues, likely reflecting saprotrophic nutritional modes in the fungi. A single Mycena OTU showed considerable colonization of both tissues, which may reflect an opportunistic parasitic or endophytic lifestyle.  相似文献   

3.
Phylogenetic analyses of Mycena sect. Calodontes using ITS previously suggested ten cryptic monophyletic ITS lineages within the Mycena pura morphospecies. Here, we compare ITS data (645 bp incl. gaps) from 46 different fruit bodies that represent the previously described ITS diversity with partial tEF-1-α (423 bp) and RNA polymerase II (RPB1) (492 bp) sequence data to test the genealogical concordance.While neither of the markers were in complete topological agreement, the branches differing between the tEF and RPB1 trees had a low bootstrap (<50) support, and the partition homogeneity incongruence length difference (ILD) tests were not significant. ILD tests revealed significant discordances between ITS and the tEF and RPB1 markers in several lineages. And our analyses suggested recombination between ITS1 and ITS2, most pronounced in one phylospecies that was identical in tEF and RPB1. Based on the agreement between tEF and RPB1, we defined 11 mutually concordant terminal clades as phylospecies inside the M. pura morphospecies; most of them cryptic. While neither of the markers showed an unequivocal barcoding gap between inter- and intraspecific diversity, the overlap was most pronounced for ITS (intraspecific diversity 0-3.5 %, interspecific diversity 0.4 %-8.8 %). A clustering analysis on tEF separated at a 1.5 % level returned all phylogenetic species as Operational Taxonomic Units (OTUs), while ITS at both a 1.5 % level and at a 3 % threshold level not only underestimated diversity as found by the tEF and RPB1, but also identified an OTU which was not a phylogenetic species. Thus, our investigation does not support the universal suitability of ITS for species recognition in particular, and emphasises the general limitation of single gene analyses combined with single percentage separation values.  相似文献   

4.
We investigated the physiological ecology of the Asian non-photosynthetic orchid Gastrodia confusa. We revealed its mycorrhizal partners by using molecular identification and identified its ultimate nutritional source by analysing carbon and nitrogen natural stable isotope abundances. Molecular identification using internal transcribed spacer and large subunit nrDNA sequences showed that G. confusa associates with several species of litter- and wood-decomposer Mycena fungi. The carbon and nitrogen isotope signatures of G. confusa were analysed together with photosynthetic plant reference samples and samples of the ectomycorrhizal epiparasite Monotropa uniflora. We found that G. confusa was highly enriched in 13C but not greatly in 15N, while M. uniflora was highly enriched in both 13C and 15N. The 13C and 15N signatures of G. confusa were the closest to those of the fruit bodies of saprotrophic fungi. Our results demonstrate for the first time using molecular and mass-spectrometric approaches that myco-heterotrophic plants gain carbon through parasitism of wood or litter decaying fungi. Furthermore, we demonstrate that, several otherwise free-living non-mycorrhizal, Mycena can be mycorrhizal partners of orchids.  相似文献   

5.
Traditional strict separation of fungi into ecological niches as mutualist, parasite or saprotroph is increasingly called into question. Sequences of assumed saprotrophs have been amplified from plant root interiors, and several saprotrophic genera can invade and interact with host plants in laboratory growth experiments. However, it is uncertain if root invasion by saprotrophic fungi is a widespread phenomenon and if laboratory interactions mirror field conditions. Here, we focused on the widespread and speciose saprotrophic genus Mycena and performed (1) a systematic survey of their occurrences (in ITS1/ITS2 datasets) in mycorrhizal roots of 10 plant species, and (2) an analysis of natural abundances of 13C/15N stable isotope signatures of Mycena basidiocarps from five field locations to examine their trophic status. We found that Mycena was the only saprotrophic genus consistently found in 9 out of 10 plant host roots, with no indication that the host roots were senescent or otherwise vulnerable. Furthermore, Mycena basidiocarps displayed isotopic signatures consistent with published 13C/15N profiles of both saprotrophic and mutualistic lifestyles, supporting earlier laboratory-based studies. We argue that Mycena are widespread latent invaders of healthy plant roots and that Mycena species may form a spectrum of interactions besides saprotrophy also in the field.  相似文献   

6.
A new species Pholiota chocenensis is described based on collections from the Czech Republic and Italy. Both the macro- and micromorphology and the the ITS-LSU rDNA sequences showed that P. chocenensis differs from all European species of Pholiota sect. Spumosae. Its key diagnostic characters are: medium-sized fruitbodies, pileus strongly glutinous, yellow-brown to orange with a rusty-brown tinge, with paler margin covered by whitish fibrillose-flocculose veil remnants, stipe covered with distinct, dense, fibrillose-floccose to floccose-scaly veil remnants of yellow-rusty to rusty-orange colour, spores ovoid, 6.4–8?×?4.4–4.8 μm, abundant cheilo- and pleurocystidia of utriform to fusiform-lageniform shape, growth on soil. Molecularly, it is unique by a 68-bp-long insert in the ITS-LSU rDNA gene which is absent in other Pholiota species. Similar European and North American taxa are compared. A possible synonymy of P. brunnescens with P. highlandensis is discussed.  相似文献   

7.
Symbiotic germination was analyzed in the myco-heterotrophic orchid Gastrodia elata. Seeds were placed on water agar medium containing a leaf-disc of Quercus accutissima that had been previously inoculated with one of six different Mycena species. Among the six fungi, KFRI1212 (HQ662845) and KFRI2121 (HQ662846) germinated 60.1 and 47.0 % seeds, respectively, while others germinated less than 3.5 %. Although KFRI1212 induced a significantly higher germination rate than KFRI2121, initiation of protocorm development was induced much faster by KFRI2121 than by KFRI1212. Molecular identification and phylogenetic analysis showed that the two fungi belonged to one clade that includes Mycena chlorophos, M. amicta and M. tenerrima, suggesting that seed germination of G. elata depends on a narrow taxonomic range of fungi. In conclusion, this study not only showed fungal preference of G. elata for seed germination but also confirmed molecular identities of mycorrhizal fungi for the first time, which will allow us to better understand the process of symbiotic events at the germination stage of G. elata.  相似文献   

8.
Identity of Ossicaulis lachnopus and O. lignatilis was studied using both classical and molecular methods. While O. lignatilis is a well-known species, O. lachnopus is almost unknown, having been resurrected to modern mycology by M. Contu in 2000. Based on collections from six European countries, both classical and molecular methods independently proved that the species really represent two separate entities. They form two well-supported clades that correlate to morphologically separable groups. The most important distinguishing characters are the size of spores, especially their length, and a pileus colour. O. lachnopus has small spores and a grey or beige-grey tinged pileus, whereas O. lignatilis has larger spores and a whitish to cream pileus, with a slight beige-greyish tinge at most. In this paper, we discuss taxonomy, ecology and distribution of both species and propose a preliminary key for their identification.  相似文献   

9.
Amyloporia pinea sp. nov. is described and illustrated on the basis of collections from southern China. Morphology and phylogenetic analysis of rDNA ITS sequences support this new species. Morphologically, it is characterized by resupinate, annual basidiocarps, cream to yellowish buff pore surface when fresh, which becomes yellowish brown to clay-buff upon drying, a dimitic hyphal system with clamped generative hyphae and inamyloid skeletal hyphae, fusoid cystidioles, and cylindrical basidiospores; moreover, it causes a brown rot. Molecular phylogeny inferred from ITS sequence data suggested a close relationship between A. pinea and Amyloporia crassa sensu lato. Antrodia subxantha has amyloid skeletal hyphae, and grouped within the Amyloporia clade, hence, it is transferred to Amyloporia, and a new combination Amyloporia subxantha is proposed.  相似文献   

10.
11.
《Comptes Rendus Palevol》2013,12(4):191-202
We describe here “miacid” taxa from the Early Eocene Paris Basin locality of Le Quesnoy (Oise, France). We describe the new species Vassacyon taxidiotis, the first European record of this genus. The other “miacids” identified from Le Quesnoy are Miacis latouri and Gracilocyon solei. The P4 of G. solei is described here for the first time. Its morphology (e.g., wide protocone, short postmetacrista) supports a close relationship with Miacis rundlei from Abbey Wood (MP8 + 9, England). The latter species is therefore classified as Gracilocyon rundlei. Three new tooth positions are known for Miacis latouri: P4, p4 and m2. They support its reference to Miacis. These specimens imply that the European species is more basal than the North American species. The fauna from Le Quesnoy shares with Dormaal the presence of Miacis latouri and Gracilocyon solei, but the “miacid” fauna from Le Quesnoy also contains Vassacyon taxidiotis. The presence in Le Quesnoy of the two former taxa supports a reference to MP7 level of the French locality. The presence of three distinct genera in European localities show that the “Miacidae” were diversified in Europe, as previously observed in North America. The genera Gracilocyon, Miacis, and Vassacyon probably dispersed from Europe to North America during the Palaeocene/Eocene boundary.  相似文献   

12.
《Phytochemistry》1998,49(8):2591-2593
Antifungal metabolites were isolated from fruiting bodies of Mycena tintinnabulum and from mycelia grown in either complex media or on oak wood. Strobilurins were produced in fruiting bodies and in mycelial cultures, whereas a new diterpene, named tintinnadiol, was isolated only from the fruiting bodies. The structure of the new compound was determined by spectroscopic methods. It exhibited cytotoxic effects.  相似文献   

13.
14.
Emerging diseases in wildlife pose challenges for conservation due to their usually rapid spread and high cause of mortality. The transmission of these diseases is a complex ecological process that involves interactions between groups of individuals, particularly in gregarious species. White-nose syndrome, caused by the fungus Pseudogymnoascus destructans, is increasingly infecting species of vespertilionid North American bats causing, in some cases, high population mortality. In this study, we modeled ecological niches projected as potential distributions for three strains of P. destructans (Asian, European and North American) and a group of species of verpertilionid bats in North America. Our model showed that the ecological niches of North American and Asian fungi strains are projected to expand into new geographic areas, with statistical significance between the two strains. In addition, our model identified the presence of all three strains of fungi in areas where the fungus has previously been documented as well as new suitable climatic areas for the establishment of P. destructans in North America: large regions of the central USA and highlands of Mexico in the Peninsula of Baja California, the Sierra Madre Occidental and Oriental, and Transvolcanic Mexican Belt. Our models identified 10 species of vespertilionid bats distributed similarly to P. destructans. Bats had a high risk of infection with WSN and a strong likelihood of dispersing the fungus.  相似文献   

15.
Synopsis We examined data from our own and published collections of intertidal and shallow littoral fishes of the North American Pacific Coast with respect to temporal and spatial trends in species composition and dominance. We compared (1) recent and past intertidal collections made five and seven years apart, respectively, for two California localities, (2) intertidal collections from twelve localities in California, Oregon, and British Columbia, and (3) intertidal versus subtidal collections at one California locality. Temporal comparisons indicated substantially lower abundance of the cottid Oligocottus snyderi at two California localities during 1984, at one locality due to depressed abundance of young. Interannual differences in abundances suggested that other tidepool fish assemblages undergo significant changes as well. Geographical comparisons indicated general similarity in species composition, with cottids predominating in tidepools although several other families also were well represented (e.g., Stichaeidae, Scorpaenidae). Eel-shaped stichaeids and pholids occurred at high densities in exposed boulder fields. Both the tidepool and boulder field assemblages showed north-south changes in species abundances. Comparison of collections from the intertidal and subtidal zones at one California locality demonstrated that fishes of these habitats form two essentially distinct assemblages, with most species restricted to or concentrated in one or the other habitat.  相似文献   

16.
The deadly poisonous Amanita phalloides is common along the west coast of North America. Death cap mushrooms are especially abundant in habitats around the San Francisco Bay, California, but the species grows as far south as Los Angeles County and north to Vancouver Island, Canada. At different times, various authors have considered the species as either native or introduced, and the question of whether A. phalloides is an invasive species remains unanswered. We developed four novel loci and used these in combination with the EF1α and IGS loci to explore the phylogeography of the species. The data provide strong evidence for a European origin of North American populations. Genetic diversity is generally greater in European vs. North American populations, suggestive of a genetic bottleneck; polymorphic sites of at least two loci are only polymorphic within Europe although the number of individuals sampled from Europe was half the number sampled from North America. Endemic alleles are not a feature of North American populations, although alleles unique to different parts of Europe were common and were discovered in Scandinavian, mainland French, and Corsican individuals. Many of these endemic European haplotypes were found together at single sites in California. Early collections of A. phalloides dated prior to 1963 and annotated using sequences of the ITS locus proved to be different species of Amanita. The first Californian collections that we confirmed as A. phalloides were made from the Del Monte Hotel (now the Naval Postgraduate School) in Monterey, and on the campus of the University of California, Berkeley, in 1938 and in 1945. These historical data are used in combination with data on A. phalloides’ current distribution to estimate a rate of spread for A. phalloides in California. Many species of ectomycorrhizal (EM) fungi have been introduced across and among continents, but with this evidence, the death cap becomes the only known invasive EM fungus in North America.  相似文献   

17.
《Comptes Rendus Palevol》2002,1(3):161-166
A fossil angiosperm wood is described for the first time from the famous Early Miocene locality of Bı́lina. It represents a fossil elm wood, attributed to Ulmoxylon marchesonii Biondi. The fossil wood can be compared to extant North American soft elms, also to Ulmus macrocarpa Hance and U. parvifolia Jacq. from China or to the European common elm U. carpinifolia Gled. The wood together with fossil leaves/fruits of Ulmus pyramidalis Goeppert forms a single natural fossil species that lived in the Bı́lina area during the Early Miocene. The influence of two types of preservation, permineralised and xylitic, on the same wood species is also discussed. To cite this article: J. Sakala, C. R. Palevol 1 (2002) 161–166.  相似文献   

18.
Three new species of Lactarius are described from Northeast China, based on morphological comparisons and analyses on ITS nrDNA sequences. Samples of these species were mostly collected from deciduous or mixed forests with oaks. Lactarius albidocinereus, a member of L. subg. Plinthogalus is very similar to European L. azonites in the morphology and the sequence data. It differs from L. azonites by more ellipsoid spores with thinner ornamentation and shorter terminal cells in the pileipellis. Lactarius dilutisalmoneus belongs to L. sect. Zonarii of L. subg. Lactarius due to the pale salmoneus subzonate pileus with glabrous margin, unchanging latex and spore ornamentation composed of isolated elements. In comparison with its relatives, i.e. European L. zonarioides and North American L. olympianus, this new species has smaller spores with more prominent ornamentation. Lactarius olivaceorimosellus, a member of L. subg. Russularia, has areolate-rimulose pileus and lacks rosettes in the pileus and stipe cortex. Apart from the concentrically cracked pileus and absence of rosettes, the species can be easily distinguished by the olivaceo-brownish tinge of the pileus and spores with more dispersed elements of the ornamentation. Of the three species, at least L. albidocinereus represents a link with the Lactarius mycota of subtropical China.  相似文献   

19.
Intercontinental introductions are widespread in the genus Spartina, with important ecological and evolutionary consequences. The native or introduced status of Spartina species is then critical with regard to biodiversity assessment, especially for vulnerable Mediterranean coastline ecosystems. Spartina versicolor was first recorded in southern France in 1849, then successively in various places on the European and North-African Mediterranean and Atlantic coasts. This species is considered to be either a European native or an invasive species introduced from North America which has a high morphological similarity to the Atlantic American species Spartina patens. We performed extensive sampling of S. versicolor in Europe and North Africa (from natural populations and herbarium collections) and compared these samples to other European and American Spartina species (including S. patens). Chromosome counts were reported for the first time and revealed that S. versicolor is tetraploid (2n = 4x = 40). Phylogenetic analyses based on chloroplast and nuclear ribosomal DNA sequences did not reveal any molecular variation within S. versicolor. In this species, a single haplotype, that is identical to one haplotype of S. patens, was found in the four chloroplast and the nuclear ribosomal ITS regions investigated. In addition, simple sequence repeat markers were used and revealed a low level of genetic diversity within S. versicolor, suggesting that the introduction of S. versicolor occurred from a narrow genetic pool of S. patens from North America.  相似文献   

20.
Several species of microsporidia are important chronic pathogens of Lymantria dispar in Europe but have never been recovered from North American gypsy moth populations. The major issue for their introduction into North American L. dispar populations is concern about their safety to native non-target insects. In this study, we evaluated the susceptibility of sympatric non-target Lepidoptera to two species of microsporidia, Nosema lymantriae and Vairimorpha disparis, isolated from European populations of L. dispar and applied in field plots in Slovakia. Application of ultra low volume sprays of the microsporidia maximized coverage of infective spores in a complex natural environment and, thus, exposure of non-target species to the pathogens. Of 653 non-target larvae collected from plots treated with V. disparis in 2002, 18 individual larvae representing nine species in four families were infected. These plots were monitored for two subsequent seasons and V. disparis was not recovered from non-target species. Of 2571 non-target larvae collected in N. lymantriae-treated sites, one larva was found to be infected. Both species of microsporidia, particularly N. lymantriae, appear to have a very narrow host range in the field, even when an inundative technique is used for their introduction. V. disparis infections in L. dispar exceeded 40% of recovered larvae in the treated study sites; infection rates were lower in sites sprayed with N. lymantriae. Several naturally-occurring pathogens were recorded from the non-target species. The most common pathogen, isolated from 21 species in eight families, was a microsporidium in the genus Cystosporogenes.  相似文献   

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