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41.
A revision of the Jurassic aphid family Genaphididae revealed that the type genus Genaphis did not have the characteristics usually attributed to this family. This discovery led to a series of taxonomic decisions. The diagnosis of the family Genaphididae is emended. The genera Aphaorus, Juraphis and Pterotella are moved to the Juraphididae, fam.n. The new family is included in the superfamily Palaeoaphidoidea. Additionally, two new species, Juraphis karataviensis sp.n. and Pterotella shartegensis sp.n. , are described. Phylogenetic relationships among the taxa of Juraphididae, the position of the family, and the distribution and palaeoecology of the taxa are discussed. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:411C1D8C‐AA45‐4311‐AA2D‐4469E44B6EDF .  相似文献   
42.
Approximately 50 taxa of butterflies in Western Europe have been described as new species or elevated to the level of species during the last 40 years. Many, especially those belonging to the genus Agrodiaetus, have unusually localized, ‘dot‐like’ distributional ranges. In the present study, we use a combination of chromosomal and molecular markers to re‐evaluate the species status of Agrodiaetus distributed west of the 17th meridian. The results obtained do not support the current designations of Agrodiaetus galloi, Agrodiaetus exuberans, and Agrodiaetus agenjoi as endemic species with highly restricted distribution ranges, but indicate that these taxa are more likely to be local populations of a widely distributed species, Agrodiaetus ripartii. Agrodiaetus violetae is shown to be a polytypic species consisting of at least two subspecies, including Agrodiaetus violetae subbaeticus comb. nov. and Agrodiaetus violetae violetae. Agrodiaetus violetae is genetically (but not chromosomally) distinct from Agrodiaetus fabressei and has a wider distribution in southern Spain than previously believed. Agrodiaetus humedasae from northern Italy is supported as a highly localized species that is distinct from its nearest relatives. We propose a revision of the species lists for Agrodiaetus taking these new data into account. The results reported in the present study are relevant to animal conservation efforts in Europe because of their implications for IUCN Red List priorities. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 130–154.  相似文献   
43.
Electrical signals (action potential and variation potential, VP) caused by environmental stimuli are known to induce various physiological responses in plants, including changes in photosynthesis; however, their functional mechanisms remain unclear. In this study, the influence of VP on photosynthesis in pea (Pisum sativum L.) was investigated and the proton participation in this process analysed. VP, induced by local heating, inactivated photosynthesis and activated respiration, with the initiation of the photosynthetic response connected with inactivation of the photosynthetic dark stage; however, direct VP influence on the light stage was also probable. VP generation was accompanied with pH increases in apoplasts (0.17–0.30 pH unit) and decreases in cytoplasm (0.18–0.60 pH unit), which probably reflected H+‐ATPase inactivation and H+ influx during this electrical event. Imitation of H+ influx using the protonophore carbonyl cyanide m‐chlorophenylhydrazone (CCCP) induced a photosynthetic response that was similar with a VP‐induced response. Experiments on chloroplast suspensions showed that decreased external pH also induced an analogous response and that its magnitude depended on the magnitude of pH change. Thus, the present results showed that proton cellular influx was the probable mechanism of VP's influence on photosynthesis in pea. Potential means of action for this influence are discussed.  相似文献   
44.
Rat blastocysts were isolated from the uterus on the 5th day after fertilization and set in culture. The effect of azathioprine (Imuran) on the blastocyst's development and on the early trophoblastic differentiation in vitro was investigated. Azathioprine, added to the medium of the blastocyst culture at various concentrations, dose dependently arrested development and had definite cytotoxic effect. In order to study the mechanism of action, a minimal dose of 5 μg/ml, which allowed the survival of about 60% of the blastocysts, was added to the medium after 48 hr of culturing. Under the effect of the substance the area of the spreading blastocyst cells was significantly restricted.
It was found, by autoradiographic methods, that the azathioprine affects the development by restraining DNA synthesis in the throphoblastic cells. Concomitantly RNA synthesis was inhibited and protein synthesis was reduced. The observations indicate, that the impairment of the in vitro differentiation of the blastocysts can be a result of the intracellular inhibitory action of the substance.  相似文献   
45.
The fossil species Architipula fragmentosa (Bode) comb. nov. (Diptera: Nematocera: Limoniidae) from the German Upper Lias (Lower Jurassic) is redescribed. This species was originally described by Bode (1953) in a new monotypic genus as Eoasilidea fragmentosa and placed in the Brachycera, with Eoasilidea as the type-genus of a new family Eoasilidae. This family is here synonymized with the Limoniidae (Nematocera), and the genus Eoasilidea is synonymized with Architipula Handlirsch .  相似文献   
46.
Tardigrades of the Taimyr peninsula with descriptions of two new species   总被引:2,自引:0,他引:2  
This is the first report on tardigrades from the Taimyr peninsula. Seventy-one species of tardigrades were recorded, new to Russian fauna and two of which are new to science. Diphascon boreale sp. nov. is closely related to D. brevipes (Marcus, 1936) but easily distinguished from it by claw structure and the absence of cuticular bars on the legs. Isohypsibius roberti sp. nov. belongs to the elegans group of the genus Isohypsibius ; it diners from other species in the group by having a long and thin buccal tube and large lunulae with small teeth on leg IV. The eggs of Ramazzottius montivagus are here described for the first time. The almost complete absence of tardigrades in and around Norilsk is noted. This is related to the heavy industrial pollution from a local nickel-copper plant.  相似文献   
47.
Abstract: Epipanfilovia oviformis gen. et sp. nov. (Neuroptera: Panfiloviidae) is described from the Middle Jurassic locality of Daohugou (Inner Mongolia, China) based on six specimens. A revised diagnosis of this family is provided. It includes two genera, Panfilovia Makarkin and Epipanfilovia gen. nov.; Osmylogramma Ponomarenko is removed from the family. Panfiloviidae is most closely related to another Jurassic family Grammolingiidae, and both are provisionally assigned to the superfamily Osmyloidea.  相似文献   
48.
A new mantispid genus and species Symphrasites eocenicus gen. sp. nov. is described from the Middle Eocene of the Messel Pit fossil site, Germany. It has been placed, with confidence, in the subfamily Symphrasinae, the fossils of which were previously unknown. A review of the known fossil species of Mantispidae is provided, and their systematic placements are discussed. Liassochrysa stigmatica Ansorge & Schlüter, 1990 is assigned to Mantispidae, and therefore Liassochrysidae is a new synonym of Mantispidae; a second, more complete specimen of Mesomantispa sibirica Makarkin, 1997 is described from the Early Cretaceous Baissa locality, Russia; Mantispidiptera Grimaldi, 2000 is excluded from the family; Vectispa Lambkin, 1986 is referred to subfamily Mantispinae; and the assignment of Whalfera Engel, 2004 to Rhachiberothidae is validated. The origin and palaeobiogeography of the mantispids are briefly discussed: the concept of ousted relicts – which assumes that former widely distributed taxa were replaced with groups originating in the tropics – is assumed to best explain the present distribution of the family.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 701–716.  相似文献   
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