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The campterophlebiid new genus and species Ctenogampsophlebia reni is described from the Middle Jurassic of Inner Mongolia, China. It shows close similarities with the Lower to Middle Jurassic genera Gampsophlebia, and Petrophlebia, with closed and short subdiscoidal cells, confirming the attribution of these two other genera to the Campterophlebiidae.  相似文献   

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An exotic wingless female insect in mid-Cretaceous Myanmar amber is described as Aethiocarenus burmanicus sp. et gen. nov. in the order Aethiocarenodea ord. nov. and family Aethiocarenidae fam. nov. The distinguishing feature of Aethiocarenus burmanicus sp. et gen. nov. is its unique head, the dorsum of which is shaped like an isosceles right triangle with the hypotenuse at the top and vertex positioned at the base of the neck. While insects with triangular-shaped heads are common today, the hypotenuse of the triangle is always located at the base of the head and attached to the neck, with the vertex at the apex of the head. Other features of the fossil are the long narrow, flat body, long slender legs, especially the hind pair that are twice the length of the abdomen, lack of wings, protruding eyes, paired ocelli, secretory glands located on the dorsum of the neck and swollen abdomen bearing paired segmented cerci.  相似文献   

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<正>A new family of so-called‘higher' planthoppers,Weiwoboidae fam.nov.,from the Lower Eocene of Yunnan is described.A new monotypic genus,Weiwoboa gen.nov.,with Weiwoboa meridiana sp.nov.is also described and illustrated.The characters of tegmen venation of the new family,its evolution,and supposed relationships are briefly discussed.  相似文献   

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Cratosmylus magnificus gen. et sp. nov., type genus and species of the new osmylid subfamily Cratosmylinae, is described from the Lower Cretaceous of the Crato Formation, Brazil. The relationships of this taxon remain uncertain within the Osmylidae, mainly due to the lack of phylogeny of the whole family. Nevertheless, it shares with the Mesozoic subfamily Saucrosmylinae the Rs curved and bent anteriorly distally, even in a more pronounced state, i.e. Rs touching R1 in its distal part.  相似文献   

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空气中氡浓度的预测   总被引:4,自引:0,他引:4  
氡是一种放射性惰性气体,它与肺癌的关系已引起人们的高度重视,世界上许多国家都开展了环境氡的研究工作;氡的母体元素铀、镭在地质环境中的分布与空气中的氡浓度水平有密切关系,通过研究地质环境中铀、镭的分布资料,就能快速定性地评价空气中氡浓度水平.  相似文献   

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