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1.
A new genus, Tologuica, with two species (T. aurorae sp. nov. and T. karhui sp. nov.), from the Middle Miocene of the Sharga locality (western Mongolia) is described. The new genus shares some characters with the extinct genera Palaeocryptonyx, Palaeortyx, and Plioperdix and with extant Coturnix. The foot structure suggests that Tologuica resembled in ecology the European genus Palaeortyx and was probably adapted to an arboreal mode of life, in contrast to the terrestrial Coturnix and Plioperdix.  相似文献   

2.
The genus Jatropha (Euphorbiaceae) contains species that are of significant economic and ornamental value. However, Jatropha breeding material is rather limited due to incomplete information regarding phylogenetic relationships among germplasm resources. Phylogenetic analyses were performed based on the internal transcribed spacer of nuclear ribosomal DNA (nrDNA ITS), two chloroplast regions (trnL-F and rbcL), and the combined (ITS+trnL-F+rbcL) dataset among twenty-five specimens representing six key Jatropha species. Phylogenetic relationships of Jatropha were well resolved between subgenus Curcas and subgenus Jatropha, and demonstrated the intermediate position of section Polymorphae among sections of both subgenera. Jatropha curcas and J. integerrima demonstrated a close phylogenetic relationship. The molecular data agreed with the morphological classification that recognized J. multifida and J. podagrica in sec. Peltatae. The distinct intraspecific divergence that occurred in J. curcas could be attributed to restricted gene flow caused by geographical isolation and different ecological conditions. Phylograms produced with trnL-F and rbcL sequence data suggested slow rates of sequence divergence among Jatropha spp., while the ITS gene tree had good resolution suggesting high genetic variation of ITS among Jatropha species.  相似文献   

3.
Pectobacterium atroseptica is known as a rod-shaped gram-negative bacterial pathogen associated with the blackleg of potato. P. atroseptica has been widely identified as the predominant agent causing tuber rot in temperate regions, a disease that leads to severe economic losses to potato industry. In this study, we provide the complete genome sequence of P. atroseptica JG10-08, which revealed that P. atroseptica strain JG10-08 carries a single 5,004,926 bp chromosome with 51.15% G+C content and harbors 4252 predicted coding genes. Phylogenetic analysis based on the genome sequences showed a close evolutionary relationship between P. atroseptica and Pectobacterium wasabiae. We discovered total 168 genes were potentially related to pathogenesis including 9 strain-specific genes encoding toxins on the genome of JG10-08. Further comparison with other species in Pectobacterium revealed a better understanding of pathogenic factors, especially secretion systems in P. atroseptica JG10-08. Collectively, the results of this research provide a solid foundation for discovering the underlying pathogenic mechanisms of P. atroseptica and offer the information to develop more effective strategies against blackleg of potatoes.  相似文献   

4.
Disperis tomaszii (Orchidaceae, Orchidoideae) from Cameroon is described and illustrated in this study. The new species is morphologically similar to Disperis nitida and Disperis thomensis. Phylogenetic analyses of selected DNA regions (ITS, matK) indicate a possible relationship between the new species and Disperis anthoceros and Disperis dicerochila. The taxonomic affinity between D. tomaszii and the aforementioned species is discussed.  相似文献   

5.
Mitochondrial genome fragments were examined in all species of the genus Capra (Bovidae, Artiodactyla). Phylogenetic analysis was carried out using 59 cytochrome b gene sequences (392 bp), and 22 sequences of the mtDNA variable fragment (402 bp). In the control region, two unique deletions were revealed. One of the deletions was found only in Capra cylindricornis (17 bp), while another one grouped C. caucasica with C. aegagrus (1 bp). The group of Caucasian wild goats splits into two clades, and furthermore, the sequences of C. caucasica demonstrate remarkable similarity to the sequences of C. aegagrus, while C. cylindricornis seems to have evolved independently for a long period of time. It was demonstrated that C. pyrenaica and C. ibex were extremely close to one another. Capra sibirica formed an outer group relative to the other species, and according to our data, was the most ancient species of the genus. On the contrary, genetic distance separating C. falconeri (the most independent species of the genus related to its morphology) from the other species is small.  相似文献   

6.
7.
Two new species of hymenolepidid cestodes belonging to the genus Armadolepis Spassky, 1954 are described from dormice (Gliridae) from the southern East European Plain and the northwestern Caucasus, Russia. Armadolepis (Bremserilepis) longisoma n. sp., with a rudimentary, unarmed rostellar apparatus is described from the fat dormouse Glis glis (Linnaeus) from the Republic of Adygeya, Russia. Additionally, A. (Armadolepis) dryomi n. sp., characterised by a well-developed rostellar apparatus and armed rhynchus is described from the forest dormouse Dryomys nitedula Pallas from Rostov Oblast’, Russia. Armadolepis (Bremserilepis) longisoma n. sp. differs from A. (Bremserilepis) myoxi (Rudolphi, 1819) in having a substantially longer strobila and cirrus-sac, wider scolex and ovary and larger rostellar pouch and testes. Armadolepis (Armadolepis) dryomi n. sp. is distinguishable from A. (Armadolepis) spasskii Tenora & Baru?, 1958, A. (Armadolepis) jeanbaeri Makarikov, 2017 and A. (Armadolepis) tenorai Makarikov, 2017 in having a substantially longer and wider strobila, and larger rostellar pouch and cirrus-sac. Furthermore, A. dryomi n. sp. can be distinguished from its congeners by the number and size of rostellar hooks and the arrangement of the testes. Phylogenetic affinities of Armadolepis were studied for the first time using partial sequences of the nuclear ribosomal 28S DNA gene. Phylogenetic analysis strongly supported the status of Armadolepis as a separate genus belonging to the “Rodentolepis clade”.  相似文献   

8.
Two novel species of bambusicolous fungi in the genus Kamalomyces, collected from northern Thailand, are described and illustrated herein. Kamalomyces bambusicola and K. thailandicus spp. nov. are typical of the genus Kamalomyces (Tubeufiaceae, Tubeufiales) and are morphologically distinct from known species with respect to their size of ascomata, asci and ascospores, ascospore septation and peridium structure, including the subiculum comprising hyphae on the host surface. Morphological examination reveals that the asexual morph of K. bambusicola is associated with its sexual morph in a subiculum forming dictyochlamydosporous conidia, which are similar to the asexual morph of Chlamydotubeufia. Phylogenetic analyses of combined LSU, ITS and TEF1-α sequence data also support these two species as distinct and confirm their phylogenetic affinities within the Tubeufiaceae. In particular, Kamalomyces shares a close phylogenetic relationship to Helicoma.  相似文献   

9.
The anoxygenic phototrophic bacterial community of the high-altitude meromictic Lake Gek-Gel (Azerbaijan) was investigated in September 2003. The highest concentration of bacteriochlorophyll e (48 μg/l) was detected at a depth of 30 m; the peak of bacteriochlorophyll a (4.5 μg/l) occurred at 29 m. Phylogenetic analysis revealed that brown-colored green sulfur bacteria Chlorobium phaeobacteroides predominated in the lake. Nonsulfur purple bacteria phylogenetically close to Blastochloris sulfoviridis were found in insignificant amounts; these organisms have not been previously reported in Lake Gek-Gel.  相似文献   

10.
11.
The complete mitochondrial genome of Zhikong scallop Chlamys farreri is 21,695 bp in length and contains 12 protein-coding genes (the atp8 gene is absent, as in most bivalves), 2 ribosomal RNA genes, and 22 transfer RNA genes. The heavy strand has an overall A+T content of 58.7%. GC and AT skews for the mt genome of C. farreri are 0.337 and ?0.184, respectively, indicating the nucleotide bias against C and A. The mitochondrial gene order of C. farreri differs drastically from the scallops Argopecten irradians, Mimachlamys nobilis and Placopecten magellanicus, which belong to the same family Pectinidae. 6623 bp non-coding nucleotides exist intergenically in the mitogenome of C. farreri, with a large continuous sequence (4763 bp) between tRNA Val and tRNA Asn . Two repeat families are found in the large continuous sequence, which seems to be a common feature of scallops. Phylogenetic analysis based on 12 concatenated amino acid sequences of protein-coding genes supports the monophyly of Pectinidae and paraphyletic Pteriomorphia with respect to Heteroconchia.  相似文献   

12.
Sequences of mitochondrial (cytochrome b) and nuclear (recombination activating gene 1–RAG1) DNA markers were obtained for two species of the genus Alburnoides, the Taskent riffle minnow A. oblongus Bulgakov 1923 and the Terek spirlin A. gmelini Bogutskaya and Coad 2009. Phylogenetic analysis revealed that A. oblongus belongs to the genus Alburnus.  相似文献   

13.
Williamson’s mouse deer, Tuagulus williamsoni (Kloss), is one of the smallest ungulates among tragulid species found in northern Thailand, and Yunnan Province, China. Here we describe Sarcocystis menglaensis n. sp., infecting two of 14 (14.3%) Williamson’s mouse deer from south-western China. By light microscopy, sarcocysts of S. menglaensis are microscopic, up to 2,170 μm in length, and have a striated sarcocyst wall with 1.5–3.6 μm long palisade-like protrusions. Transmission electron microscopy observations revealed that sarcocyst wall is of “type 10f”, and has numerous villar protrusions folded over the cyst wall. The villar protrusions contained microtubules dispersed throughout the protrusions. Phylogenetic analysis based on 18S rDNA and mitochondrial cox1 gene sequences indicated that S. menglaensis shared a close affinity with species of Sarcocystis Lankester, 1982 from ruminants, which utilise felids as definitive hosts.  相似文献   

14.
Species in the genus Basidiophora (Oomycota, Peronosporales) are pathogens causing downy mildew disease on several closely related plant hosts in the family Asteraceae, including the genera Conyza, Erigeron, Solidago, and Symphyotrichum. Despite their widespread occurrence, little is known about the diversity, biology, and economic impact of downy mildew pathogens of ornamental or wild plants in the Asteraceae. In June 2017, Solidago sphacelata plants of the cultivar ‘Golden Fleece’ were found in the state of Delaware, USA, showing typical symptoms of downy mildew disease. Initial morphological observations indicated the specimen belonged to the genus Basidiophora. Phylogenetic analysis of a sequence matrix of the partial cox2 mitochondrial gene using Bayesian and maximum likelihood methods showed that the Basidiophora isolate from S. sphacelata represents an undescribed species that is here described as B. delawarensis. This new species constitutes the third accepted species in the genus Basidiophora and can be distinguished from other Basidiophora species by differences in size of sporangia and sporangiophores and nucleotide sequence divergence. This new species poses a potential threat to its host, warranting close monitoring and the implementation of disease management programs.  相似文献   

15.
The genus Sinocyclocheilus is a representative group of cave creatures. However, genetic studies on Sinocyclocheilus are rare. The primary objective of this study was to explore the structure and feature of the complete mitochondrial genome of S. multipunctatus, and reconstruct the mitogenomic phylogeny of Sinocyclocheilus. The mitochondrial DNA of S. multipunctatus was amplified by overlapping PCR fragments. The mitogenome was assembled by the SeqMan and annotated using MitoAnnotator. The phylogenetic tree was established using the Bayesian inference and Maximum likelihood methods. The mitogenome of S. multipunctatus is a typical circular molecule of 16,586 bp with base composition A (31.25%), T (25.90%), G (16.35%), and C (26.50%), and consists of 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs) genes, two ribosomal RNAs, and a 931 bp control region. Phylogenetic analysis reveals two clades in the Sinocyclocheilus with robust support. S. multipunctatus is close to a newly discovered cavefish, S. ronganensis. We obtained and described the complete mitogenome of S. multipunctatus, and investigated its phylogenetic status, which may provide a valuable resource for future phylogenetic analyses and population genetic studies in Sinocyclocheilus.  相似文献   

16.
The evolution of genes related to sex and reproduction in fish shows high plasticity and, to date, the sex determination system has only been identified in a few species. Solea senegalensis has 42 chromosomes and an XX/XY chromosome system for sex determination, while related species show the ZZ/ZW system. Next-generation sequencing (NGS), multi-color fluorescence in situ hybridization (mFISH) techniques, and bioinformatics analysis have been carried out, with the objective of revealing new information about sex determination and reproduction in S. senegalensis. To that end, several bacterial artificial chromosome (BAC) clones that contain candidate genes involved in such processes (dmrt1, dmrt2, dmrt3, dmrt4, sox3, sox6, sox8, sox9, lh, cyp19a1a, amh, vasa, aqp3, and nanos3) were analyzed and compared with the same region in other related species. Synteny studies showed that the co-localization of dmrt1-dmrt2-drmt3 in the largest metacentric chromosome of S. senegalensis is coincident with that found in the Z chromosome of Cynoglossus semilaevis, which would potentially make this a sex proto-chromosome. Phylogenetic studies show the close proximity of S. senegalensis to Oryzias latipes, a species with an XX/XY system and a sex master gene. Comparative mapping provides evidence of the preferential association of these candidate genes in particular chromosome pairs. By using the NGS and mFISH techniques, it has been possible to obtain an integrated genetic map, which shows that 15 out of 21 chromosome pairs of S. senegalensis have at least one BAC clone. This result is important for distinguishing those chromosome pairs of S. senegalensis that are similar in shape and size. The mFISH analysis shows the following co-localizations in the same chromosomes: dmrt1-dmrt2-dmrt3, dmrt4-sox9-thrb, aqp3-sox8, cyp19a1a-fshb, igsf9b-sox3, and lysg-sox6.  相似文献   

17.
Birch trees inhabiting the high-altitude Hyrcanian forest (the southern shores of the Caspian Sea of Iran and Azerbaijan) are classified in the EN (endangered) category of the International Union for Conservation of Nature (IUCN). Taxonomic status and phylogenetic relationship of Iranian populations, molecular taxonomy, and biogeography of the genus Betula in the world have been considered. Four remnant populations of Betula were selected from north and northwestern parts of Iran. The internal ITS and trnH-psbA intergenic spacer regions were sequenced. Based on the trnH-psbA and ITS, Iranian birch and white birch were placed in a clade, but based on trnH-psbA divided into two subclades. Phylogenetic trees based on ITS and trnH-psbA data did not completely support the morphological classification. Network analysis confirms a close relationship of B. pendula with B. platyphylla and B. papyrifera with B. humilis, and B. ermanii were in a group with the other tetraploid species of the subgenus Neurobetula. Divergence time analysis showed that about 75 Ma ago the Betula genus separated from the other genus of Betulaceae and then divided into two main clades in Oligocene. Our divergence analysis supports that two subgenera of Betulenta and Betulaster are the oldest subgenera in the genus Betula and they date back to Eocene. The ancestral reconstruction suggests that ancestors of the genus Betula originated from Southeast Asia.  相似文献   

18.
Two articles on fossil Lestremiinae (Diptera: Cecidomyiidae) in Rovno amber (Perkovsky and Fedotova, 2004; Fedotova and Perkovsky, 2004) are reviewed and discussed. As a result, the following gall midges species are considered Lestremiinae incertae sedis: + Aprionus admirandus Fed., + Conarete laesus Fed., + Heterogenella sparsa Fed., + Micromyia convoluta Fed., + Peromyia autonoma Fed., + Peromyia miranda Fed., + Peromyia sukachevae Fed., + Peromyia zherikhini Fed. (all in Perkovsky and Fedotova, 2004), + Campylomyza falciformis Fed., + Campylomyza superposita Fed., + Neurolyga declinata Fed., + Strobliella appropinquata Fed., and + Strobliella capitata Fed. (all in Fedotova and Perkovsky, 2004).  相似文献   

19.
Phylogenetic interrelation between 40 strains of the Bacillus cereus group has been established using BcREP fingerprinting. The PCR method has shown that the frequency of occurrence of the genes of cytotoxin K (cytK) and hemolysin II (hlyII) is 61% and 56%, respectively, and the gene of the hemolysin II regulator (hlyIIR) occurs together with hlyII. Comparison of the results of fingerprinting, PCR, and RFLP of the toxin genes showed that bacteria with the hlyII + and cytK + genotypes did not form separate clusters. However, microorganisms with the similar fingerprints were shown to have toxin genes of the same type. The proposed variant of RFLP analysis made it possible to clearly distinguish between the cytK1 and cytK2 genes. Twenty-three strains having the cytK genes carried no cytK1 dangerous for mammals. Additionally, the entire collection of microorganisms was tested for the ability to grow at 4°C. This property was revealed for five strains, which should most likely be classified as B. weihenstephanensis. Two of the five psychrotolerant microorganisms carried the hemolysin II gene variant of the same type according to RFLP. None of the five strains had the cytK gene. These strains did not form close groups upon clustering by the applied method of Bc-REP fingerprints.  相似文献   

20.
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