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31.
In the second part of the revision of fossil Metretopodidae, a new species of the genus Metretopus Eaton, 1901 is described and illustrated based on a male imago. Metretopus dividussp. nov. is the second fossil species of the genus. Distinguishing characters for its separation from other fossil and recent representatives of Metretopus are discussed. http://www.zoobank.org/urn:lsid:zoobank.org:act:BCC5CB69-8014-4DA1-A0DA-DCF714969081  相似文献   
32.
The following new genus and seven new species of Cossonine weevils (Curculionidae: Cossoninae) are described from Dominican amber: Acamptus exilipes Poinar and Legalov, n. sp. (similar to A. rigidus), Caulophilus camptus Poinar and Legalov, n. sp. (similar to C. bennetti), Caulophilus elongatus Poinar and Legalov, n. sp. (similar to C. swensoni), Caulophilus ruidipunctus Poinar and Legalov, n. sp., Dryotribus pedanus Poinar and Legalov, n. sp. (similar to D. amplioculus), Ogygius obrieni Poinar and Legalov, n. gen., n. sp. (similar to the genus Apotrepus), and Stenotrupis pumilis Poinar and Legalov, n. sp. (similar to S. breviscapus). A key to the Dominican amber species of the genus Caulophilus is provided. Based on the extant weevil fauna, it appears that the Hispaniolan Cossonine were more diverse in the Tertiary than at present. http://zoobank.org/urn:lsid:zoobank.org:pub:14D1CFC0-4967-4D22-888B-0DE3E157D6BD  相似文献   
33.
A new species of Dryophthorus and two new species of Stenommatus (Coleoptera: Dryophthoridae) are described from Dominican amber. Dryophthorus microtremus n. sp. is characterised by monochrome dorsal scales, nearly parallel sides of the pronotum, wide elytral intervals and the elytral apex only slightly narrowed. Stenommatus tanyrhinus n. sp. is characterised by an elongate rostrum 4.5 times as long as wide in the middle. S. leptorhinus is characterised by small body size, a thin rostrum 3.0 times as long as wide in the middle, wide striae and a narrow prosternal process. This brings the total number of species of Dryophthorini in Dominican amber to five, which is more than half the number of extant species.http://www.zoobank.org/urn:lsid:zoobank.org:pub:4329D0DA-57BD-4CEA-9464-ABD5D1577FC9  相似文献   
34.
During a palaeontological excavation of amber at the site named San Just, in the Utrillas-Escucha area of Teruel Province, northeastern Spain, a rich fauna from the Albian (Early Cretaceous) was discovered. Among it, three specimens of Thysanoptera were found that are here attributed to the new genus Hispanothrips n. gen. in the family Stenurothripidae Bagnall 1923. Phylogenetic analyses were conducted that support the resurrection of the family Stenurothripidae and its replacement for Adiheterothripidae Shumsher 1946.  相似文献   
35.
36.
Macrosiagon deuvei n. sp., the second fossil representative of this extant genus of Ripiphoridae: Ripiphorinae: Macrosiagonini is described from the lowermost Eocene amber of Oise (France). The new species is compared with the extant species of the genus. Taxonomic position of other two fossil representatives of the family described from France by Perrichot et al. (2004) is discussed. The genus Paleoripiphorus Perrichot et al. 2004 is tentatively transferred from Ripiphorinae to Ripidiinae.  相似文献   
37.
New Ceratopogonidae from the Early Cretaceous amber of Hammana (Central Lebanon) are studied. Five new species (Lebanoculicoides daheri sp. nov., Protoculicoides krzeminskii sp. nov., Archiaustroconops annae sp. nov., Archiaustroconops hammanensis sp. nov., and Archiaustroconops dominiakae sp. nov.) are characterized, described, illustrated, and compared with other Cretaceous taxa. New keys for species of the three genera Lebanoculioides, Protoculicoides, and Archiaustroconops, but also for all genera of Lebanese fossil biting midges, are proposed.  相似文献   
38.
Cyanobacteria are effective producers of bioactive metabolites, including both acute toxins and potential pharmaceuticals. In the current work, the biological activity of 27 strains of Baltic cyanobacteria representing different taxonomic groups and chemotypes were tested in a wide variety of assays. The cyanobacteria showed strain-specific differences in the induced effects. The extracts from Nodularia spumigena CCNP1401 were active in the highest number of tests, including protease and phosphatase inhibition assays. Four strains from Nostocales and four from Oscillatoriales increased proliferation of mitogen-stimulated human T cells. In antimicrobial assays, Phormidium sp. CCNP1317 (Oscillatoriales) strongly inhibited the growth of six fouling Gammaproteobacteria. The growth of monocotyl Sorghum saccharatum was inhibited by both toxin-producing and ‘non-toxic’ strains. The Baltic cyanobacteria were also found to be a rich source of commercially important enzymes. Among the 19 enzymatic activities tested, alkaline phosphatase, acid phosphatase, esterase (C4 and C8), and naphthol-AS-BI-phosphohydrolase were particularly common. In the cyanobacterial extracts, different peptides which may have been responsible for the observed effects were identified using LC-MS/MS. Their structures were classified to microcystins, nodularins, anabaenopeptins, cyanopeptolins, aeruginosins, spumigins and nostocyclopeptides.  相似文献   
39.
Chrysosphaerella coronasircumspina Wujek & Kristiansen and Spiniferomonas bilacunosa Takahashi have been shown by electron microscopy to be regular members of the phytoplankton society in an oligotrophic Norwegian mountain lake. This is the first published record of these species in Norway.  相似文献   
40.
Abstract

This article documents and interprets stratigraphical changes in fractionation of Fe, Mn, Mg, K, Pb, Cu and Zn in the Sa1/2 sediment core from a coastal freshwater lake, Lake Sarbsko (northern Poland). The elements were sequentially extracted from the samples to distinguish five geochemical fractions: exchangeable, acid-extractable, reducible, oxidisable and residual. The analyses revealed substantial variations in geochemical partitioning of the elements and showed no correlation between the fractionation patterns and lithology of the sediments. In the sediments of Lake Sarbsko, iron is mainly bound to sulfides. Potassium occurs in its residual form. Magnesium and zinc are associated with carbonates and aluminosilicates, while copper occurs in compounds with organic matter and sulfides. Lead is found in connection with aluminosilicates and, to a lesser extent, with sulfides and organic matter. Manganese is partitioned between the oxidisable, acid-extractable, and exchangeable fractions. Heavy metals and potassium display the overall tendency to reduce the contents of their residual forms towards the top of the depositional sequence. Fe, Mn, Mg and Zn were found to be the most susceptible to post-sedimentary mobilisation.  相似文献   
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