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A collection of Polychaeta made by the author during 1969 from the coast of Kuwait has been studied. Nineteen species, belonging to 17 genera and 11 families, are described. Nine species are named as new to science (two new genera) and ten species are recorded as new to the fauna of the Arabian Gulf. Also, the available information on the geographical distribution has been given for each new record.  相似文献   
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Abstract: Lower Ordovician faunas of Bohemia (Perunica), Baltica and North China include the oldest known representatives of the Order Craniida, but otherwise in Gondwana and associated terranes, the record of craniides is sparse. Pseudocrania insperata sp. nov. from the Lashkarak Formation of the Eastern Alborz Mountains is the first and as yet only record of the occurrence of craniides in the Middle Ordovician (Darriwilian) of Iran and temperate to high latitude peri‐Gondwana. Pseudocrania was known hitherto only from the Middle Ordovician of Baltoscandia and the Chu‐Ili terrane of Kazakhstan.  相似文献   
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We used measurements of museum skins to assess morphological differences between the 22 currently recognized species of wheatear and to identify correlations between morphological features, behavioural traits and degrees of sympatry between species. Ground-dwelling species of steppe-like habitats have long tarsi, long claws and short tails; some are migratory and have long pointed wings and non-emarginated primaries ( O. isabellina and O. oenanthe ), while others are sedentary and have more rounded and slotted wings ( O. bottae , O. heuglini and O. pileata ). Vegetation-tolerant species ( O. pleschanka , O. hispanica , O. cypriaca and O. deserti ) have relatively long tails, short tarsi, long middle toes and long claws. The rock-dwelling species have short tarsi, long toes and short claws; they can be either relatively heavy ( O. leucura and O. monticola ) or light, like the wheatears inhabiting the most arid areas ( O. monacha , O. leucopyga and O. alboniger ). Although sedentary, the latter show intermediate characteristics between sedentary and migratory species, having relatively pointed wings with non-emarginated primaries. Together with their low wing-loadings, these traits may be related to the scarcity of resources in their habitats, which obliges them to make frequent and long flights. The clear morphological differentiation between wheatear species appears to be mainly related to their migratory and foraging habits, but seems to bear no relation to their degree of sympatry.  相似文献   
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Efficiency of imidacloprid and pymetrozine on population growth parameters of cabbage aphid, Brevicoryne brassicae L. (Homoptera: Aphididae) was determined using demographic toxicology by leaf dip method. At first, bioassay tests were performed. The LC50 value and confidence limit for imidacloprid and pymetrozine were 1.61 × 10^-5 mol/L (0.74 × 10^-5-2.66 × 10^-5) and 2.14 × 10^-4 mol/L (1.24 × 10^-4-3.40 × 10^-4), respectively. To evaluate the sublethal effect of two insecticides on population growth parameters of cabbage aphid, LC30 concentrations of imidacloprid and pymetrozine were used at 5 mol/L and 30 mol/L. The experiments were carried out in a incubator at 20±1℃, 60% ± 5% RH and 16:8 (L:D) photoperiod on canola seedlings, Brassica napus L. var. 'PF'. Net fecundity rate decreased in both insecticide-treated populations. Intrinsic rates of increase (rm) were lower in imidacloprid and pymetrozine treatments than in controls. Intrinsic birth rates also decreased in treated populations. There was a relative increase in intrinsic death rates of treated populations. The mean generation times and doubling time were also lower in populations treated with insecticides than in controls. There was a considerable reduction in the average numbers of nymphs reproduced per female as compared with the control. The average longevity of female adults in the control was significantly different from those treated with imidacloprid and pymetrozine. However, there was no significant differences in aphid life-table parameters between the two insecticide-treated populations (P 〉 0.01).  相似文献   
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Abstract. Type specimens have been examined of eleven Australian species of the tetramerous Aphelinidae described by Girault in the genera Apteroptrbc, Metacasca, Neocasca, Oa and Pteroptrixella. Apteroptrix and Oa are synonym-ized with Archenomus. O. biguttata is considered a nomen dubium. M. copemici is transferred to Neocasca. Dahmsiella genji. is proposed for N. shillingsworthi. Pteroptrixella is suspected of being a senior synonym of Metacasca , but the former genus is represented by an incomplete specimen. A key is given to the tetramerous genera of the Aphelinidae.  相似文献   
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Abstract:  The eastern Alborz Mountains of Iran comprise a significant peri-Gondwanan terrane relevant to the early evolution of late Cambrian – early Ordovician brachiopods incorporated into the emerging benthic biota of the Paleozoic Evolutionary Fauna. A low diversity brachiopod assemblage from the late Tremadocian unit of the Lashkarak Formation contains six new species including the polytoechioideans Polytoechia and Protambonites and the orthoideans Paralenorthis, Ranorthis, Tarfaya and Xianorthis . The fauna preserves the earliest records of Polytoechia , unknown previously outside Laurentia and the Uralian margin of Baltica, and of Paralenorthis and Ranorthis , which were widespread along Gondwanan margins and in Baltica from the Floian (Arenig), plus Xianorthis , known hitherto only from the Floian of South China. The enigmatic Tarfaya has an impunctate shell fabric and setigerous perforations along the posterior margin, indicating placement within the Orthoidea in a new Family Tarfayidae. New species of Polytoechia , Protambonites , Paralenorthis, Ranorthis , Tarfaya , Xianorthis are described.  相似文献   
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