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1.
Palaxius salataensis Brönnimann, Cros and Zaninetti, 1972 is described from early Carboniferous stromatolite mounds of a fore-reef slope setting from Laibin, Guangxi, South China. This is the oldest occurrence of internally structured crustacean coprolites. The geographic distribution and stratigraphic range of the ichnospecies as well as paleoecological implications of this new record of P. salataensis are discussed.  相似文献   

2.
The first Permian occurence of a crustacean coprolite association, composed ofFavreina martellensis Brönnimann & Zaninetti (1972),Palaxius salataensis Brönnimann, Cros & Zaninetti (1972) and an undeterminated form are recorded from Late Permian reef limestones of the Oman Mountains.  相似文献   

3.
The fossil anomuran coprolite form-genera are defined by the type of the cross section of the longitudinal canals which pierce the fecal pellet. Arrangement and number of longitudinal canals within the 2 bilaterally symmetric groups of canals are the principal elements for the definition of form-species of anomuran coprolites. To-date the 4 thalassinid form-generaFavreina Brönnimann, 1955,Palaxius Brönnimann & Norton, 1960,Helicerina Brönnimann & Masse, 1968, andParafavreina Brönnimann, Caron & Zaninetti, 1972, and the single galatheid form-genusThoronetia Brönnimann, Caron & Zaninetti, 1972, have been established.  相似文献   

4.
5.
The following paper describes the foraminiferal fauna and associated faunal assemblages of the bedded and reef carbonates of the Upper Triassic (most probably Rhaetian) Nayband Formation, which are exposed in a section south of the small town of Bagher-Abad, northeast of Esfahan. Foraminifers are extremely rare in sponge- or coral-dominated bioconstructions and in the bedded carbonates of the Nayband Formation in central Iran. Some carbonate beds are composed of bioclastic wackstone/packstone. These are exposed in the solenoporacean horizon at the uppermost part of the section. Here, the aulotortid- and trocholinid-type foraminifers are relatively abundant. The following foraminiferal taxa with different abundances were found within the carbonates of the investigated section: Trocholina umbo Frentzen, T. turris Frentzen, T. gracilis Blau, Aulotortus tumidus (Kristan-Tollmann), Aulotortus tenuis (Kristan), Aulotortus friedli (Kristan-Tollmann), Coronipora etrusca (Pirini), Semiinvoluta clari Kristan, Turrispirillina? licia variabilis Blau, Galeanella? laticarinata Al-Shaibani, Carter and Zaninetti, Ophthalmidium sp., Agathammina sp., “Sigmoilinaschaeferae Zaninetti, Planiinvoluta carinata Leischner, Planiinvoluta sp., Nubecularia sp., Endothyra sp., Paeolituonella sp. and some sessile agglutinated and nodosariid types. All mentioned taxa are very rare, except the involutinid and trocholinid types. The following species are described as new: Trocholina blaui nov. sp., Spirilina? iranica nov. sp., and Coronipora serraforma nov. sp. Trocholina blaui is usually attached to solenoporacean thalli. Four foraminiferal associations, which are named after the occurrence of the abundant species, were distinguished as Aulotortus tumidus association, Aulotortus friedli association, Trocholina umbo association, and Trocholina blaui association. Aulotortid types and Trocholina umbo were found within the bioclastic wackstone/packstone carbonates. Trocholina blaui is abundant in solenoporacean framestones. The foraminiferal association of investigated carbonates contains a mixed fauna, known from Upper Triassic–Liassic in the Tethyan realm. Carbonates of the whole investigated section are dated—due to occurrence of the genus Aulotortus, with species A. tumidus (Kristan-Tollmann), A. tenuis (Kristan), and A. friedli (Kristan-Tollmann)—as Upper Triassic (most probably Rhaetian). The “typical” foraminifers occurring in the reef biotopes in the northwestern Tethys are either missing or extremely rare in the Iranian bioconstructions.  相似文献   

6.
Deep-sea hydrothermal vents are considered to be one of the most spectacular ecosystems on Earth. Microorganisms form the basis of the food chain in vents controlling the vent communities. However, the diversity of bacterial communities in deep-sea hydrothermal vents from different oceans remains largely unknown. In this study, the pyrosequencing of 16S rRNA gene was used to characterize the bacterial communities of the venting sulfide, seawater, and tubeworm trophosome from East Pacific Rise, South Atlantic Ridge, and Southwest Indian Ridge, respectively. A total of 23,767 operational taxonomic units (OTUs) were assigned into 42 different phyla. Although Proteobacteria, Actinobacteria, and Bacteroidetes were the predominant phyla in all vents, differences of bacterial diversity were observed among different vents from three oceanic regions. The sulfides of East Pacific Rise possessed the most diverse bacterial communities. The bacterial diversities of venting seawater were much lower than those of vent sulfides. The symbiotic bacteria of tubeworm Ridgeia piscesae were included in the bacterial community of vent sulfides, suggesting their significant ecological functions as the primary producers in the deep-sea hydrothermal vent ecosystems. Therefore, our study presented a comprehensive view of bacterial communities in deep-sea hydrothermal vents from different oceans.  相似文献   

7.
The morphology and taxonomy of eight rare desmids (Zygnematophyceae) from Central Europe are studied, i.e. six taxa from Slovakia [Tortitaenia bahusiensis (Nordstedt et Lütkemüller) Coesel, Closterium limneticum Lemmermann var. fallax R??i?ka, Euastrum sublobatum de Brébisson in Ralfs, morpha, Cosmarium simplicius (W. et G.S. West) Grönblad, Pachyphorium canadense (Irénée-Marie) G. H. Tomaszewicz et Hindák, stat. et comb. nova, Staurastrum bloklandiae Coesel et Joosten], one species from Poland (Spirotaenia bacillaris Lütkemüller) and Austria (Cosmarium geminatum Lundell). All desmids taxa are new records for the country of their origin.  相似文献   

8.
Four species of Pronotalia Gradwell (Hymenoptera, Eulophidae: Tetrastichinae) are recorded from the Lagodekhi Reserve (Georgia). Formerly, only P. carlinarum (Szelényi et Erdös) was known from Transcaucasia (Armenia) (Kostjukov, 1978). Pronotalia fiorii (Domenichini), P. orobanchiae Graham, and P. trypetae Gradwell are recorded for Georgia and Transcaucasia for the first time. In addition to these species, only 4 species are known from Europe and Anatolia: P. erzurumica Doganlar, P. hungarica (Erdös), P. inflata Graham, and P. tortumensis Doganlar; thus, 50% of Pronotalia species from Europe and Anatolia occur in the Lagodekhi Reserve.  相似文献   

9.
The study of the cell wall structure was performed for ten species of Euastrum: E. ansatum (Ehrenb.) Ralfs, E. bidentatum Näg., E. binale (Turp.) Ehrenb. ex Ralfs, E. dubium Näg., E. elegans (Bréb.) Kütz. ex Ralfs, E. germanicum (Schmidle) W. Krieger, E. oblongum (Grev.) Ralfs ex Ralfs, E. pectinatum Bréb. ex Bréb. in Ralfs, E. validum West et G.S.West, E. verrucosum (Ehrenb.) ex Ralfs. The investigation of the cell wall ultrastructure has established for the first time that the pore canal in 6 of 10 species always has a coiled form to some degree. Three species (E. germanicum, E. pectinatum, and E. verrucosum) have both coiled and straight canals, and E. ansatum has only straight ones. A new type of pores (P7), typical only for representatives of the genus Euastrum, was also noted. In addition, a simple and effective method of preparing desmidium algal cells for investigation with transmission electron microscope has been developed.  相似文献   

10.
A total of 104 species belonging to 15 genera of the subfamily Aphidiinae (Hymenoptera, Aphidiidae) are reported from the former USSR: Aclitus Förster, 1862 (1), Adialytus Förster, 1862 (6), Aphidius Nees, 1802 (39), Chaetopauesia Mackauer, 1967 (1), Diaeretiella Starý, I960 (1), Diaeretellus Starý, I960 (4), Diaeretus Förster, 1862 (1), Lysiphlebia Starý et Schlinger, 1967 (1), Lysiphlebus Förster, 1862 (13), Metaphidius Starý et Sedlag, 1959 (1), Paralipsis Förster, 1862 (2), Pauesia Quilis, 1931 (29), Protaphidius Ashmead, 1862 (3), Pseudaclitus Starý, 1974 (1), and Xenostigmus Smith, 1944 (1). Thirteen species, Aphidius (Aphidius) erysimi Starý, I960, A. (A.) stigmaticus Rakhshani et Tomanovi?, 2011, A. (A.) viaticus Sedlag, 1969, A. (Euaphidius) plocamaphidis Starý, 1973, Diaeretellus palustris Starý, 1971, Lysiphlebus (Phlebus) alpinus Starý, 1971, L. (Ph.) orientalis Starý et Rakhshani, 2010, Pauesia (Pauesia) goidanichi Starý, 1966, P. (P.) jezoensis (Watanabe, 1941), P. (P.) montana Starý, 1966, P. (Paraphidius) konoi (Watanabe, 1941), and P. (Par.) similis Starý, 1966, are recorded from Russia for the first time. The distribution of 32 species already known from Russia is specified.  相似文献   

11.
Simple and convergent synthesis of a tetra- and a trisaccharide portions of an antitumor compound Julibroside J28, isolated from Albizia julibrissin, that showed significant in vitro antitumor activity against HeLa, Bel-7402 and PC-3M-1E8 cancer cell lines is reported. The tetrasaccharide has been synthesized as its p-methoxyphenyl glycoside starting from commercially available d-glucose, l-rhamnose and l-arabinose. The trisaccharide part has been synthesized from commercially available N-acetyl d-glucosamine, d-fucose and d-xylose using simple protecting group manipulations. Sulfuric acid immobilized on silica has been used successfully as a Brönsted acid catalyst for the crucial glycosylation steps.  相似文献   

12.
The myrmeoleontoid Neuroptera fauna of Kyrgyzstan comprises 34 species-group taxa, among which 23 are recorded from the republic for the first time. Epacanthaclisis alaica Krivokhatsky, 1998 is known only from the holotype collected in the Alai Mt. Range; Kirghizoleon cubitalis Krivokhatsky et Zakharenko, 1994 is known from Kyrgyzstan and from the Hissar Mt. country in Tajikistan; and Mesonemurus vartianorum Hölzel, 1972 is distributed from the Tien Shan to Afghanistan. 26 species are common in Kyrgyzstan and are fairly evenly distributed over its territory. New synonymies are established: Macronemurus persicus (Navás, 1915) = Barreja persica Navás, 1915, = Barreja amoena Hölzel, 1972, syn. n.; Myrmecaelurus acerbus (Walker) = Myrmeleon acerbus Walker, 1853; = Myrmecaelurus varians Navás, 1913, syn. n.; = Myrmecaelurus aequans Navás, 1913, syn. n.; = Myrmecaelurus nematicus Navás, 1932, syn. n. The polymorphous structure of the widely variable Macronemurus persicus is shown, and three its color morphs are distinguished: Macronemurus persicus var. persica (Navás, 1915), var. graciosa var. n., and var. amoena (Hölzel, 1972). Data on the antlion and owlfly fauna of some other Palaearctic countries are supplemented.  相似文献   

13.
There are many types of neurons that intrinsically generate rhythmic bursting activity, even when isolated, and these neurons underlie several specific motor behaviors. Rhythmic neurons that drive the inspiratory phase of respiration are located in the medullary pre-Bötzinger Complex (pre-BötC). However, it is not known if their rhythmic bursting is the result of intrinsic mechanisms or synaptic interactions. In many cases, for bursting to occur, the excitability of these neurons needs to be elevated. This excitation is provided in vitro (e.g. in slices), by increasing extracellular potassium concentration (K out ) well beyond physiologic levels. Elevated K out shifts the reversal potentials for all potassium currents including the potassium component of leakage to higher values. However, how an increase in K out , and the resultant changes in potassium currents, induce bursting activity, have yet to be established. Moreover, it is not known if the endogenous bursting induced in vitro is representative of neural behavior in vivo. Our modeling study examines the interplay between K out , excitability, and selected currents, as they relate to endogenous rhythmic bursting. Starting with a Hodgkin-Huxley formalization of a pre-BötC neuron, a potassium ion component was incorporated into the leakage current, and model behaviors were investigated at varying concentrations of K out . Our simulations show that endogenous bursting activity, evoked in vitro by elevation of K out , is the result of a specific relationship between the leakage and voltage-dependent, delayed rectifier potassium currents, which may not be observed at physiological levels of extracellular potassium.  相似文献   

14.
Marine sponges and other sessile macro-organisms were collected at a shallow water hydrothermal site in Eyjafjörður, Iceland. Bacteria were isolated from the organisms using selective media for actinomycetes, and the isolates were screened for antimicrobial activity. A total of 111 isolates revealed antimicrobial activity displaying different antimicrobial patterns which indicates production of various compounds. Known test strains were grown in the presence of ethyl acetate extracts from one selected isolate, and a clear growth inhibition of Staphylococcus aureus was observed down to 0.1 % extract concentration in the medium. Identification of isolates shows different species of Actinobacteria with Streptomyces sp. playing the largest role, but also members of Bacilli, Alphaproteobacteria and Gammaproteobacteria. Sponges have an excellent record regarding production of bioactive compounds, often involving microbial symbionts. At the hydrothermal vents, however, the majority of active isolates originated from other invertebrates such as sea anemones or algae. The results indicate that antimicrobial assays involving isolates in full growth can detect activity not visible by other methods. The macro-organisms inhabiting the Eyjafjörður hydrothermal vent area host diverse microbial species in the phylum Actinobacteria with antimicrobial activity, and the compounds responsible for the activity will be subject to further research.  相似文献   

15.
An aerobic hyperthermophilic CO-oxidizing archaeon, Sulfolobus sp. strain ETSY, was isolated and characterized. Presently, it is the only known representative of both hyperthermophiles and Archaea that is capable of aerobic oxidation of CO, a gas of global importance for atmospheric chemistry and of local importance as one of the substrates for the microbial communities of hydrothermal vents. In the genome of Sulfolobus sp. ETSY we found genetic determinants of aerobic CO oxidation: a coxFMSLDE gene cluster and two separately located coxG genes. We also found such gene clusters in the genomes of certain strains of Sulfolobus islandicus and Sulfolobus solfataricus. On the phylogenetic tree of large subunits of aerobic CO-dehydrogenases (CoxLs), these proteins of Sulfolobus representatives formed a compact cluster within one of the branches formed by bacterial form I CoxLs. Thus we argue that the ability to oxidize CO aerobically was acquired by Sulfolobus ancestor from Bacteria relatively late in the evolution, presumably after the formation of the atmosphere with a high oxygen content.  相似文献   

16.
The genus Phaeophilacris Walk. is divided into two subgenera: Phaeophilacris s. str. and Speluncacris Sjöst. The latter name, originally proposed as a generic one and synonymized with Phaeophilacris s. l., is restored as a subgeneric name. The former genera Opilionacris Sjöst. and Cavernacris Sjöst. previously synonymized with Phaeophilacris s. l. are considered as synonyms of the subgenus Speluncacris. Four new species (Ph. (S.) malawi sp. n., Ph. (S.) boldyrevi sp. n., Ph. (S.) dmitrievi sp. n., and Ph. (S.) gigantea sp. n.) and three new subspecies (Ph. (S.) bredoides mangochi subsp. n., Ph. (S.) bredoides mutinondo subsp. n., and Ph. (Ph.) townsendi aethiopica subsp. n.) of the genus Phaeophilacris are described.  相似文献   

17.
Six new genera, three tribes and one subfamily are added to the list of known hosts for the enigmatic endoparasitic fungus Myrmicinosporidium Hölldobler. Aphaenogaster senilis, Cataglyphis hispanica, Crematogaster auberti, Goniomma hispanicum, Messor barbarus, Tapinoma nigerrimum and Tapinoma simrothi were collected from olive groves and detected as infected with spores of the fungus. Pheidole pallidula and Tetramorium semilaeve were also found to be infected. The finding of seven hosts (seven genera, three subfamilies) from a single olive grove is an evidence that the fungus has a phylogenetically wide host spectrum and is, therefore, a generalist microparasite. Portugal is also a new country for Myrmicinosporidium.  相似文献   

18.
A total of 64 species belonging to 10 genera of the subfamily Trioxinae (Hymenoptera, Aphidiidae) are recorded from the former USSR: Betuloxys Mackauer, 1960 (6), Binodoxys Mackauer, 1960 (11), Calaphidius Mackauer, 1961 (1), Falciconus Mackauer, 1959 (2), Harkeria Cameron, 1900 (1), Lipolexis, Förster, 1862 (1), Monoctonia Starý, 1962 (2), Monoctonus Haliday,1833 (6), Sergeyoxys Davidian, 2016 (1), and Trioxys Haliday, 1833 (33). Four species, Harkeria angustivalva (Starý, 1959), Monoctonia japonica Rakhshani et Tomanovic, 2015, Monoctonus mali van Achterberg, 1989, and Trioxys iziphia Mackauer, 1967 are recorded from Russia for the first time. The distribution of 20 species already known from Russia is clarified.  相似文献   

19.
Puccinia tatrensis Urban onGeum reptans in Czechoslovakia is recognized as a subspecies ofPuccinia sieversiae Arth.Puccinia waldsteiniae, P. gei andP. gei-parviflori appear to be the most ancient rusts known on the tribeGeeae and it is assumed that their common ancestral form was already present in the Cretaceous period.Puccinia sieversiae is more advanced and has its centre of origin and spread in Central Asia. Phylogenetically most advanced and at the same time most differentiated from each other are species ofPhragmidium, i.e.P. circumvallatum andP. miyabeanum.  相似文献   

20.
The prokaryotic communities of four salterns (Bingöl, Fadlum, Kemah, and Tuzlagözü) in Turkey were examined and compared using the cultivation and cultivation-independent methods [fluorescence in situ hybridization (FISH) and 454 pyrosequencing]. FISH analysis with universal probes revealed that feeding waters carried 1.6 × 102–1.7 × 103 cells mL?1, while crystallization ponds carried 3.8 × 106–2.0 × 107 cells mL?1 that were mostly haloarchaea, including square cells (except for Kemah). High-throughput 16S rRNA-based gene sequencing showed that the most frequent archaeal OTUs in Bingöl, Fadlum, Tuzlagözü, and Kemah samples were affiliated with Haloquadratum (76.8 %), Haloarcula (27.8 %), Halorubrum (49.6 %), and Halonotius (59.8 %), respectively. Bacteroidetes was the dominant bacterial phylum in Bingöl and Fadlum, representing 71.5 and 79.5 % of the bacterial OTUs (respectively), while the most abundant bacterial phylum found in the Kemah saltern was Proteobacteria (79.6 %). The majority of the bacterial OTUs recovered from Tuzlagözü belonged to the Cyanobacteria (35.7 %), Bacteroidetes (35.0 %), and Proteobacteria (25.5 %) phyla. Cultivation studies revealed that the archaeal isolates were closely related to the genera Halobacterium, Haloarcula, and Halorubrum. Bacterial isolates were confined to two phyla, Proteobacteria (Alphaproteobacteria and Gammaproteobacteria classes) and Bacteroidetes. Comparative analysis showed that members of the Euryarchaeota, Bacteroidetes, Proteobacteria, and Cyanobacteria phyla were major inhabitants of the solar salterns.  相似文献   

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