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In this paper we have attempted to clarify the taxonomy and nomenclature of thirteen taxa of the genus Cortinarius subgenus Telamonia (sections Hydrocybe, Fraternii) well represented in the southwestern Mediterranean area of Europe (C. atrocoeruleus, C. bombycinus, C casimiri, C. contrarius, C. decipiens, C. fraternus, C. gallurae, C. hoffmannii, C. petroselineus, C. sertipes, C. subturibulosus, C. urdaibaiensis and C. vernus). To this end we have performed a combined study of morphological and molecular data (rDNA ITS sequences). The morphological analysis was carried out on 114 collections and the molecular analysis involved 31 of the 114 collections, including 11 type collections (types for C. casimiri and C. fraternus were not available). In addition, a study of spores under field emission scanning electron microscopy (FESEM) was conducted. The results of the combined analysis allowed us to asign the studied material to five species (C. casimiri s.l., C. decipiens s.l., C. gallurae, C. subturibulosus s.l. and C. vernus s.l.). Thus, all collections from more continental areas, which were originally identified as six different taxa (C. atrocoeruleus, C. contrarius, C. decipiens, C. fraternus, C. sertipes, C. flexipes fo. sertipes) corresponded to C. decipiens sensu lato, a widely distributed, genetically and morphologically variable species. Cortinarius casimiri is also found in such habitats, but it is confirmed as distinct taxon. Collections from Mediterranean sclerophyllous communities correspond to C. gallurae, C. vernus sensu lato and C. subturibulosus sensu lato. Due to close phylogenetic relationships we propose the new combinations C. casimiri var. hoffmannii (=C. decipiens var. hoffmannii non C. hoffmannii) and C. subturibulosus var. bombycinus (=C. bombycinus), and the new variety C. vernus var. nevadavernus (=C. vernus H. Lindstr. & Melot sensu auct.).  相似文献   

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Two of the oldest known silicoflagellate-bearing sediments, lower Albian at Ocean Drilling Program Site 693 in the Weddell Sea of Antarctica and Santonian in the Devon Island sequence of the Canadian Archipelago, are re-examined with a focus on silicoflagellate genera Variramus, Cornua, and Gleserocha that lack basal rings, a feature appearing during late Santonian/early Campanian time within the genus Corbisema. The extraordinary variability of Variramus aculeifera is studied, and a new genus Gleserocha is proposed for taxa with apical structures made of three struts, but without pikes. This new genus includes previously described Variramus wisei and Cornua tapiae and new species G. harrisonii, and is here proposed as a genus transitional between Variramus and Cornua. Two unusual new species of Cornua, C. deflandrei and C. witkowskiana, are also described and a revised terminology is proposed for the skeletal components of Cornua and closely related genera.  相似文献   

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In the present study, two new species of Gyrodactylus are described from Profundulus oaxacae, a fish endemic to the Pacific slope of Oaxaca State, Mexico. Fishes were collected within their distribution range in 5 localities in the Atoyac-Verde River. Gyrodactylus montealbani n. sp. and G. zapoteco n. sp. were erected and characterized morphologically (sclerites of the attachment apparatus and the male copulatory organ) and molecularly (sequences of the Internal Transcribed Spacer region of rDNA). The haptoral sclerites of the new species are similar to those of Gyrodactylus iunuri and Gyrodactylus tepari, both recently described from the goodeid fish Goodea atripinnis, from the Mexican States of Jalisco and Querétaro, respectively; and to Gyrodactylus xtachuna described from the poeciliid Poeciliopsis gracilis in Veracruz State, Mexico – nonetheless, these species can all be discriminated based on their marginal hook morphology. Specimens of G. montealbani n. sp. and G. zapoteco n. sp. were sequenced, and were aligned with sequences of 25 other Gyrodactylus spp. Both Maximum likelihood and Bayesian inference analyses indicated that the two new species are members of independent, well-supported lineages – these are the first Gyrodactylus species described from Profundulus oaxacae.  相似文献   

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Ferula species of the section Palaeonarthex contains various sesquiterpenoids. While C-15 terpenoid coumarins of the iresan type are the most characteristic constituents of species in the subsection Foetidissimae, sesquiterpene lactones and C-10 terpenoid coumarns are found in the subsection Tumidae and esters of the sesquiterpene alcohols in the subsection Jaeschkaenae. The biogenetic relationships of the Ferula sesquiterpenoids and their chemosystematic value are discussed.  相似文献   

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Diverse collections of Cortinarius pseudofallax from several European countries were studied using morphological characters and ITS1-5.8S-ITS2 genes from sequence data. They were compared with some close species such as C. cedriolens, C. neofallax and C. parvannulatus. All these taxa share some features like a light brown pileus, a stipe provided with a more or less developed whitish veil, small and well-ornamented spores and, above all, a typical strong and perfumed acidulous smell; in addition. the phylogenetic tree built with the ITS gene sequences of these vouchers showed that they clustered in a well-supported clade, here treated as section Parvuli. Our specimens of C. pseudofallax are morphologically described and illustrated with pictures of fresh specimens and basidiospores seen under SEM. A discussion of their taxonomic relationships with another group of similar species belonging to the C. decipiens sensu lato complex is presented.  相似文献   

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《Mycoscience》2014,55(4):252-259
Cytospora species are the most serious and widespread pathogens associated with canker disease on multiple plants. In this study, three species, i.e., Cytospora sophoricola, C. chrysosperma, and C. sophorae, which were isolated from Sophora in China, are described and illustrated based on their morphological characteristics and phylogenetic analyses. Cytospora sophoricola was distinguished clearly by its larger disc, multiple ostioles, cystic and multiple locules, and specific cultural characteristics, i.e., protruding fruiting bodies. Maximum parsimony and maximum likelihood analysis showed that it did not cluster with any known species of Cytospora, so it is described as a new species. Cytospora sophorae is a previously reported species from Sophora, which is redescribed based on new isolates and additional observations. Another species was identified as C. chrysosperma, which is reported for the first time on Sophora, so Papilionaceae is shown to be a new host family for C. chrysosperma. The morphological affinities of these species with related taxa are discussed, while the phylogenetic relationships of these species with other fungus in the genus Cytospora were elucidated based on their internal transcribed spacer (ITS) rRNA region sequences.  相似文献   

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The geographical distribution and analysis of the essential oils of species from three sections of Hypericum L. (Guttiferae/Clusiaceae/Hypericaceae) from Portugal are presented. Hypericum perfoliatum (section Drosocarpium) grows wild in the centre and south of Portugal; Hypericum humifusum and Hypericum linarifolium are both from section Oligostema, the former occurring throughout the country, while the second is distributed mainly in the north and centre; Hypericum pulchrum (section Taeniocarpium) is confined to the littoral north of Portugal. The essential oils were obtained by distillation–extraction, hydrodistillation and distillation in a modified Marcusson apparatus from the dried aerial parts of the different populations and were analysed by GC and GC–MS. Monoterpene hydrocarbons constituted the main fraction in all oils (43–69%, 53–85%, 28–45% and 48–65% for H. perfoliatum, H. humifusum, H. linarifolium and H. pulchrum, respectively). Sesquiterpene hydrocarbons (2–13%, 6–18%, 21–27% and 16–18%, respectively) and a third fraction of non-terpenic compounds (20–29%, 3–16%, 2–14% and 5–11%, respectively) from the four species attained relatively high amounts in all oils. Within each species, no major differences were detected in the essential oil composition, despite the fact that different locations, phenological phases and extraction methodologies were used. Notwithstanding the dominance of α-pinene in all four species' oils, cluster and principal components analysis on the identified components showed that the range of α-pinene, β-pinene and n-nonane supported a separation of the four species. The essential oil composition of the four species showed some qualitative resemblances, which correlate well with the taxonomical classification based on morphological characters.  相似文献   

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In this study, the genetic diversity and identification of Bradyrhizobium symbionts of Crotalaria zanzibarica, the most widely-distributed invasive legume in Taiwan, and other sympatric legume species growing along riverbanks of Taiwan were evaluated for the first time. In total, 59 and 54 Bradyrhizobium isolates were obtained from C. zanzibarica and its coexisting legume species, respectively. Based on the multilocus sequence analysis (MLSA) of concatenated four housekeeping genes (dnaK-glnII-recA-rpoB gene sequences, 1901 bp), the 113 isolates displayed 53 unique haplotypes and grouped into 21 clades. Of these clades, 11 were found to be congruent to already defined Bradyrhizobium species, while the other 10 clades were found to not be congruent to any defined species. In particular, the C. zanzibarica isolates belong to 14 MLSA clades, six of which overlapped with the isolates of coexisting legumes. According to the nodA gene sequences (555 bp) obtained from the 105 isolates, these isolates were classified into three known nodA clades, III.2, III.3 and VII and were further clustered into 10 groups. Furthermore, the C. zanzibarica isolates were clustered into 8 nodA groups, five of which overlapped with the isolates from coexisting legumes. Additionally, the nodA genes of the isolates from native species were dominated by Asian origin, while those from C. zanzibarica were dominated by American origin. In conclusion, C. zanzibarica is a promiscuous host capable of recruiting diverse Bradyrhizobium symbionts, some of which are phylogenetically similar to the symbionts of coexisting legumes in Taiwan.  相似文献   

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Four new species of Entoloma s.l. (Agaricales) from southern China   总被引:1,自引:0,他引:1  
Four new Entoloma s.l. species (E. azureosquamulosum, E. caeruleoflavum, E. hainanense, and E. subtenuicystidiatum) are described from southern China. E. azureosquamulosum fits well within the section Rhamphocystotae, E. caeruleoflavum belongs to the section Entoloma, E. hainanense is placed in the section Calliderma, and E. subtenuicystidiatum is a species in the section Cyanula. Preliminary phylogenetic analyses for the four new species are provided based on ITS and LSU sequences in this paper.  相似文献   

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A new species, Haplopappus graniticus, is described and illustrated. Its relationships seemingly lie with section Tonestus but its narrow heads and imbricated phyllaries are anomalous in that section.  相似文献   

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The chemosystematic value of UV-absorbing leaf constituents was considered in previously uncharacterised representatives of Aloe section Pictae, the problematic maculate species complex. Comparative data indicate that the anthrone C-glycoside, 6′-malonylnataloin (7-hydroxychrysaloin 6′-O-malonate) is typical of maculate species in East Africa, but is unconvincing as a synapomorphy for section Pictae. A naphthalene derivative found widely in Aloe, plicataloside, was detected in Aloe greatheadii. Biogeographical trends were observed in the occurrence of the flavonoids isoorientin (luteolin-6-C-glucoside) and isovitexin (apigenin 6-C-glucoside). Isoorientin is a common constituent of tropical and sub-tropical species of Aloe, whereas isovitexin is restricted to a few southern African species. Isoorientin and isovitexin co-occur in the southern African maculate species Aloe parvibracteata, and the disjunct West African maculate species, Aloe macrocarpa. This is the first report of isoorientin and isovitexin in maculate species of Aloe; the presence of flavonoids in section Pictae is of taxonomic interest.  相似文献   

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Ambrosia beetles (Coleoptera: Scolytinae) are associated with strictly entomochoric and mutualistic fungi. We studied the mycobiota associated with Scolytodes unipunctatus, ambrosia beetles that infest Cecropia trees in Central America. Isolates were characterized using morphology and rDNA sequences (ITS region, LSU, and SSU rDNA). Four species are described here: Raffaelea scolytodis sp. nov. (Ophiostomatales), Gondwanamyces scolytodis sp. nov., Custingophora cecropiae sp. nov., and Graphium sp. (Microascales). The genus Custingophora is emended to include Knoxdaviesia anamorphs of Gondwanamyces based on uniformity of DNA sequences and phenotype.  相似文献   

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Several aspects of the biology of Cycloramphus species of the Atlantic Forest are still poorly known, which makes it difficult to understand their historical relationships. Therefore, we were stimulated to promote a comparative cytogenetic analysis of several species of the genus Cycloramphus. The study of Cycloramphus acangatan, C. boraceiensis, C. brasiliensis, C. carvalhoi, C. eleutherodactylus, C. fuliginosus, C. lutzorum, and C. rhyakonastes, revealed that these eight species share a diploid number 2n = 26. Cycloramphus fuliginosus presented the most distinct karyotype, due to the presence of subtelocentric chromosomes in pairs 1 and 4. The main diagnostic feature observed in the other species was the presence of one pair of telocentric chromosomes in C. boraceiensis, C. carvalhoi, and C. eleutherodactylus, while the remaining species presented karyotypes composed exclusively of biarmed chromosomes. Constitutive heterochromatin was predominantly located in pericentromeric regions in all species, although additional C-bands detected on telomeric and/or interstitial regions were partially species-specific. Silver staining revealed Ag-NORs located on the pair 6 in six species, whereas C. acangatan presented it on pair 1 and a multiple pattern was observed in C. fuliginosus with three Ag-NOR bearing chromosomes. Fluorescent in situ hybridization using rDNA probe was performed in specimens of C. eleutherodactylus from Paraná, C. lutzorum, and C. rhyakonastes, which did not reveal inactive NOR. Despite the apparent highly conserved diploid number, data on the karyotype microstructure characterize the cytogenetic profile of the genus and may contribute to clarify the phylogenetic relationships among Cycloramphus, the Cycloramphinae, or even the family Cycloramphidae.  相似文献   

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Dark, septate endophytes (DSE) were isolated from roots and needles of dwarf Picea abies and from roots of Vaccinium spp. growing on a permafrost site in the Jura Mountains in Switzerland. Two of the isolates sporulated after incubation for more than one year at 4 °C. One of them was a hitherto undescribed helotialean ascomycete Phaeomollisia piceae gen. sp. nov., the other was a new species of Phialocephala, P. glacialis sp. nov. Both species are closely related to DSE of the Phialocephala fortinii s. lat.-Acephala applanata species complex (PAC) as revealed by phylogenetic analyses of the ITS and 18S rDNA regions. Morphologically dissimilar fungi, such as Vibrissea and Loramyces species, are phylogenetically also closely linked to the new species and the PAC. Cadophora lagerbergii and C. (Phialophora) botulispora are moved to Phialocephala because Phialocephala dimorphospora and P. repens are the closest relatives. Several Mollisia species were closely related to the new species and the PAC according to ITS sequence comparisons. One DSE from needles of Abies alba and one from shoots of Castanea sativa formed Cystodendron anamorphs in culture. Their identical 18S sequences and almost identical ITS sequences indicated Mollisia species as closest relatives, suggesting that Mollisia species are highly euryoecious.  相似文献   

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