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1.
Yeast abundance and species diversity in the lichens collected at the Kindo Peninsula (Karelia) were studied. A total of 14 lichen species analyzed belonged to the genera Bryoria, Cladonia, Hypogymnia, Icmadophila, Nephroma, Peltigera, and Ramalina. Abundance of cultured yeasts in lichens was intermediate between soil and phyllosphere. The average yeast number on lichens was ~2.5 × 103 CFU/g, while it exceeded 8 × 103 CFU/g on plants and reached only 1 × 103 CFU/g in soil. Yeast population of different parts of Cladonia lichens was found to vary significantly in abundance, species diversity, and community structure. The highest yeast abundance and diversity were revealed in the growth zone. Fifteen yeast species were isolated from lichens, including 6 basidiomycetous and 9 ascomycetous ones. Unlike soils and plants, yeast population of lichens consisted mainly of ascomycetous species, with predominance of Candida sphagnicola and anamorphous yeasts of the genus Dothiora. These results show that yeasts from different taxonomic and ecological groups are a necessary component of lichens; conditions favoring the preservation and development of specific yeast communities differing from the typical soil and phyllosphere yeast complexes are formed in the lichens of northern taiga forests.  相似文献   

2.
Data on semiaquatic epilithic and aquatic lichens predominant in the surf and littoral zones of the test site Cape Berezovyi (Southern Baikal) obtained in 2002–2005 are presented. This is the first report on the distribution of rare and unfamiliar aquatic lichen species, Collema ramenskii Elenk. and Verrucaria spp. on the stony littoral of the western Baikal shore. The lichens form dense aggregations at depths from 1–1.5 to 3–3.5 m, where Verrucaria spp. thalli densely cover 60–70% of the rock debris. Only occasional lichens are observed below 7 m. Features of the penetration of aquatic Verrucaria spp. thalli into the rock debris were examined by electron microscopy. The chemical composition of aquatic lichens was analyzed for the first time. It was shown that aquatic lichens are capable of accumulating Ti, Ga, Y, and rare earths poorly soluble in the water of the stony littoral. The original data point to the active role of aquatic lichens in biogeochemical destruction of rocks of the Baikal stony littoral.  相似文献   

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Background

Moths of genus Dendrolimus (Lepidoptera: Lasiocampidae) are among the major pests of coniferous forests worldwide. Taxonomy and nomenclature of this genus are not entirely established, and there are many species with a controversial taxonomic position. We present a comparative evolutionary analysis of the most economically important Dendrolimus species in Eurasia.

Results

Our analysis was based on the nucleotide sequences of COI and COII mitochondrial genes and ITS2 spacer of nuclear ribosomal genes. All known sequences were extracted from GenBank. Additional 112 new sequences were identified for 28 specimens of D. sibiricus, D. pini, and D. superans from five regions of Siberia and the Russian Far East to be able to compare the disparate data from all previous studies. In total, 528 sequences were used in phylogenetic analysis. Two clusters of closely related species in Dendrolimus were found. The first cluster includes D. pini, D. sibiricus, and D. superans; and the second, D. spectabilis, D. punctatus, and D. tabulaeformis. Species D. houi and D. kikuchii appear to be the most basal in the genus.

Conclusion

Genetic difference among the second cluster species is very low in contrast to the first cluster species. Phylogenetic position D. tabulaeformis as a subspecies was supported. It was found that D. sibiricus recently separated from D. superans. Integration of D. sibiricus mitochondrial DNA sequences and the spread of this species to the west of Eurasia have been established as the cause of the unjustified allocation of a new species: D. kilmez. Our study further clarifies taxonomic problems in the genus and gives more complete information on the genetic structure of D. pini, D. sibiricus, and D. superans.
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Colletotrichum cliviae is a fungal species reported both as pathogen and endophyte with broad geographical distribution. Some purported isolates of this species have been assigned to different taxa, including Colletotrichum aracearum, Colletotrichum orchidearum and Colletotrichum. sichuanensis, for which a preliminary analysis of extensive multilocus (ACT, GAPDH, ITS, TUB2) data in this study revealed high sequence similarity with C. cliviae. We further reassessed the species delineation by using the coalescent method of the generalized mixed Yule-coalescent (GMYC) and Poisson Tree Processes (PTP). Single and multilocus gene trees strongly supported a C. cliviae s. lat. clade including the four species. This clade unfolded eight subclades grouped into three distinct lineages, but no monophyly of any of the four species. GMYC and PTP analyses confidently supported the evolutionary independence of these lineages. C. sichuanensis and C. cliviae, except one isolate, formed the largest lineage. The second lineage was made up of isolates named C. aracearum and some of C. orchidearum sharing the haplotype and the third lineage accommodated two isolates named C. cliviae and C. orchidearum. This finding suggests the synonymization of C. sichuanensis with C. cliviae whereas the taxonomic status of C. aracearum and C. orchidearum still needs clarification. This study lays great stress upon the use of comprehensive data for sequence-based characterisation of species in the C. cliviae s. lat. It also presents the first report of C. cliviae in tropical Africa and on citrus host.  相似文献   

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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   

10.
Two new species of Conidiobolus were isolated from Anhui Province, China. A polyphasic taxonomic approach comprising morphological characteristics and molecular data (the nuclear large subunit of ribosomal DNA and the translation elongation factor 1 alpha gene sequences) was applied to determine their novel taxonomic status in the genus Conidiobolus. The new species C. mirabilis is a sister group to C. thromoides, but morphologically differs by smaller primary conidia and a unique formation of zygospores among two to four adjacent hyphal segments. The other new species C. pachyzygosporus characterized with thick-walled zygospores is phylogenetically closely related to C. antarcticus, C. couchii, and C. osmodes.  相似文献   

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Recent molecular studies have suggested the monophyly of Bolusiella, a small orchid genus comprising five species and one subspecies from Continental Africa, but sampling has been limited. Using the species delimitation presented in the recent taxonomic revision of the genus, this study aimed to confirm the monophyly of Bolusiella and assess the interspecific relationships using a comprehensive sampling and various analytical methods. DNA sequences of one nuclear spacer region (ITS-1) and five plastid regions (matK, rps16, trnL–trnF, trnC–petN, and ycf1) from 20 specimens representing all five species of the genus were analyzed using static homology, dynamic homology, and Bayesian methods. The monophyly of both the genus Bolusiella and each of its five species was confirmed, corroborating the previously published taxonomic revision. The use of dynamic homology methods was not conclusive for this particular group. The results of the total evidence analysis (combining all six sequence regions) using the dynamic homology approach yielded a slightly different hypothesis regarding interspecific relationships (namely the exchange of B. talbotii and Bolusiella iridifolia as the earliest diverging lineage), probably because the nodes in question are supported by a small subset of conflicting characters, compared to the hypotheses resulting from the static homology and Bayesian methods, which are congruent with the results of previous studies.  相似文献   

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An overview of the literature changes in the systematics of algae in the order Laminariales (Phaeophyta) based on molecular phylogentic data is given. In a recent taxonomic revision by Lane et al., [45], the number and status of the families traditionally included in the order have been revised. One family was transferred to the order Tilopteridales; a new family, the Costariaceae, was described; and the genus Laminaria was split into 2 genera, Laminaria and a newly resurrected genus Saccharina. These innovations have necessitated a systematic revision of the Far Eastern species of the Laminariales. Our genetic studies indicate that 2 species of Laminaria and 12 intraspecific taxa (1 subspecies and 11 forms) from the Russian Pacific coasts should be transferred to the genus Saccharina. The following new nomenclatural combinations are proposed: Saccharina bongardiana, comb. nov. (including 4 forms: f. bifurcata, f. subsessilis, f. subsimplex, f. taeniata) and Saccharina gurjanovae, comb. nov. (including f. lanciformis). In addition, new nomenclature combinations are proposed for intraspecific taxa of the Laminaria species (L. angustata, L. cichorioides, L. japonica) that have already been transferred to the genus Saccharina [45]. These include S. angustata subsp. sibirica, comb. nov., 4 new combinations for the forms of S. cichorioides (f. coriacea, f. sacchalinensis, f. sikotanensis, and f. sinuicola), and 2 new combinations for the forms of S. japonica (f. diabolica, and f. longipes). The taxonomic status of the rest of the members of the Laminariales known from the seas of the Russian Far East is discussed. Laminariaceous algae in this area represent 6 of the 8 known families currently included in the Laminariales (Chordaceae, Pseudochordaceae, Alariaceae, Arthrothamnaceae, Laminariaceae, and Costariaceae).  相似文献   

15.
The genus Cerradomys, comprising eight species, is distributed mainly in transitional, dry, open and inland South American biomes like Caatinga, Cerrado, and Chaco. However, Cerradomys goytaca is restricted to very harsh ecosystems along the Quaternary coast sandy plains (restingas) of the Rio de Janeiro and Espírito Santo states, in southeastern Brazil. Cytochrome b and IRBP DNA data were used for elucidating the phylogenetic relationships of Cerradomys and estimating the time of divergence of different evolutionary lineages, while morphometric analyses were carried out for analyzing the rate of phenotypic evolution. Our findings showed that the first speciation events occurred in the Pliocene and early Pleistocene, leading to the C. marinhus, C. maracajuensis, and C. scotti distributed in central and western Brazil while species from eastern Brazil (C. langguthi, C. vivoi, C. subflavus, and C. goytaca) originated in the middle to late Pleistocene. Cerradomys goytaca populations diverged from inland C. subflavus ca. 0.29 MYBP with an accelerated rate of phenotypic evolution resulting in unique craniometric attributes, likely due to the strong selective pressures imposed by harsh habitats.  相似文献   

16.
Morphological revision of Fulvifomes robiniae, as well as phylogenetic inferences based on nITS and nLSU markers, indicated that the species has a narrower concept in its morphology and distribution. Other morphologically related taxa arise from this taxonomic approach. Fulvifomes cedrelae is not accepted as a synonym of F. robiniae, and Fulvifomes squamosus sp. nov. is described as new based on Peruvian specimens. Based on morphology, phylogenetic relationships and host distributions, the taxonomic implication for the genus and other related taxa are discussed.  相似文献   

17.
The waveform and some characteristics of the electric organ discharges have been studied in 11 individuals of Cyphomyrus petherici, the only representative of the genus in the Nilotic fauna. The discharge is characterized by three to five phases with a prevalence of the second phase in terms of the relative amplitude and a wide variability of the total duration of discharge (from 212 to 558 μs). The comparison of the discharges of the species under study with those in the congeneric species and representatives of the genus Pollimyrus (which previously encompassed C. petherici) demonstrates a general similarity of the C. petherici discharges with those of Cyphomyrus, but not Pollimyrus. This is in agreement with the correspondence of the discharge characteristics observed in other mormyrids to the phylogenetic position and taxonomic status of the species.  相似文献   

18.
This study assessed the taxonomic hierarchy of the phylum Firmicutes as well as elucidated the isolation and classification states of novel Firmicutes species isolated from Korean territory. The hierarchical classification system of the phylum Firmicutes has been developed since 1872 when the genus Bacillus was first reported and has been generally adopted since 2001. However, this taxonomic hierarchy is still being modified. Until Feb. 2017, the phylum Firmicutes consisted of seven classes (Bacilli, Clostridia, Erysipelotrichia, Limnochordia, Negativicutes, Thermolithobacteria, and Tissierellia), 13 orders, 45 families, and 421 genera. Firmicutes species isolated from various environments in Korea have been reported from 2000, and 187 species have been approved as of Feb. 2017. All Firmicutes species were affiliated with three classes (Bacilli, Clostridia, and Erysipelotrichia), four orders (Bacillales, Lactobacillales, Clostridiales, and Erysipelotrichales), 17 families, and 54 genera. A total of 173 species belong to the class Bacilli, of which 151 species were affiliated with the order Bacillales and the remaining 22 species with the order Lactobacillales. Twelve species belonging to the class Clostridia were affiliated within only one order, Clostridiales. The most abundant family was Bacillaceae (67 species), followed by the family Paenibacillaceae (56 species). Thirteen novel genera were created using isolates from the Korean environment. A number of Firmicutes species were isolated from natural environments in Korean territory. In addition, a considerable number of species were isolated from artificial resources such as fermented foods. Most Firmicutes species, belonging to the families Bacillaceae, Planococcaceae, and Staphylococcaceae, isolated from Korean fermented foods and solar salterns were halophilic or halotolerant. Firmicutes species were isolated from the whole territory of Korea, especially large numbers from Provinces Gyeonggi, Chungnam, and Daejeon.  相似文献   

19.
Till this day, there is not much known about the phylogeny of the Secale genus; therefore, in our research, we tried to shed some lights on the issue of rye (Secale genus) taxonomy. The genetic diversity and phylogenetic relationships were evaluated using 13,842 DArTseq? polymorphic markers. The model-based clustering (STRUCTURE software) separated our 84 samples into three main clusters: perennial cluster, annual cluster, and S. sylvestre cluster. The same result was obtained using Neighbour Joining tree and self-organizing maps. Secale sylvestre, S. strictum, and S. cereale are the three main species of the Secale genus. Three samples of rye are in basal positions in phylogenetic trees. These accessions share ancient morphological characters and are probably the ancestors of different lineages within Secale. Annual Secale taxa, with the exception of S. sylvestre, create one mutual taxon. We have found out that the semi-perennial taxa of S. cereale var. multicaule and S. strictum subsp. ciliatoglume are genetically closest to the annual species of S. cereale. Phylogenetic signals for semi-perennial and annual taxa are also present in S. strictum subsp. africanum. SNP-based analysis revealed that evolution of annual S. cereale has already begun in S. strictum subsp. africanum. The results showed that S. vavilovii cannot be considered as a separate species but a subspecies of S. cereale Secale cereale subsp. dighoricum is a hybrid. It is still not clear whether we can consider S. strictum subsp. strictum and S. strictum subsp. kuprijanovii as two separate species.  相似文献   

20.
A multigene phylogeny was constructed, including a significant number of representative species of the main lineages in the Xylariaceae and four DNA loci the internal transcribed spacer region (ITS), the large subunit (LSU) of the nuclear rDNA, the second largest subunit of the RNA polymerase II (RPB2), and beta-tubulin (TUB2). Specimens were selected based on more than a decade of intensive morphological and chemotaxonomic work, and cautious taxon sampling was performed to cover the major lineages of the Xylariaceae; however, with emphasis on hypoxyloid species. The comprehensive phylogenetic analysis revealed a clear-cut segregation of the Xylariaceae into several major clades, which was well in accordance with previously established morphological and chemotaxonomic concepts. One of these clades contained Annulohypoxylon, Hypoxylon, Daldinia, and other related genera that have stromatal pigments and a nodulisporium-like anamorph. They are accommodated in the family Hypoxylaceae, which is resurrected and emended. Representatives of genera with a nodulisporium-like anamorph and bipartite stromata, lacking stromatal pigments (i.e. Biscogniauxia, Camillea, and Obolarina) appeared in a clade basal to the xylarioid taxa. As they clustered with Graphostroma platystomum, they are accommodated in the Graphostromataceae. The new genus Jackrogersella with J. multiformis as type species is segregated from Annulohypoxylon. The genus Pyrenopolyporus is resurrected for Hypoxylon polyporus and allied species. The genus Daldinia and its allies Entonaema, Rhopalostroma, Ruwenzoria, and Thamnomyces appeared in two separate subclades, which may warrant further splitting of Daldinia in the future, and even Hypoxylon was divided in several clades. However, more species of these genera need to be studied before a conclusive taxonomic rearrangement can be envisaged. Epitypes were designated for several important species in which living cultures and molecular data are available, in order to stabilise the taxonomy of the Xylariales.  相似文献   

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