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Yan Zheng Jun Chen Junqiang Zhang Haichun Zhang 《Alcheringa: An Australasian Journal of Paleontology》2020,44(1):115-120
Zheng, Y., Chen, J., Zhang, J. & Zhang, H., 6 August 2019. New fossil sawflies (Hymenoptera, Xyelidae) from the Middle Jurassic of northeastern China. Alcheringa 44, 115–120. ISSN 0311-5518.Magnaxyela rara gen. et sp. nov. and Abrotoxyela curva sp. nov. (Xyelidae, Macroxyelinae, Gigantoxyelini) are described from the Middle Jurassic Jiulongshan Formation at Daohugou Village, Inner Mongolia, China. The two new species are confidently assigned to tribe Gigantoxyelini of subfamily Marcroxyelinae based on their wing venation and various other morphological characters. Magnaxyela rara is established based on the following forewing characters: pterostigma sclerotized completely, Sc two-branched and meeting R before origin of Rs, 1-Rs as long as 1-M, but shorter than Rs?+?M, R curved bewteen 1r-rs and 2r-rs and cell 2r longer than 1r. Abrotoxyela curva is differentiated from congeneric forms by the two-branched vein Sc of the forewing, Sc2 short and inclined towards the base of the wing, 1-Rs, 1-M and Rs?+?M nearly equal in length, crossvein 1m-cu longer than 1cu-a. The fossils described herein increase the diversity of the Mesozoic Xyelidae.Yan Zheng* [zhengyan536@163. com], Jun Chen* [ubiscada@sina. com], and Junqiang Zhang [zhangjunqiang@lyu. edu. cn], Institute of Geology and Paleontology, Linyi University, Shuangling Road, Linyi 276000, PR China; Haichun Zhang [hczhang@nigpas. ac. cn], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, East Beijing Road, Nanjing 210008, PR China. *Also affiliated with: State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, East Beijing Road, Nanjing 210008, PR China. 相似文献
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Dong Hoon Shin Chang Seok Oh Sang Jun Lee Jong Yil Chai Jaehyup Kim Soong Deok Lee Jun Bum Park In-hwa Choi Hye Jung Lee Min Seo 《Journal of archaeological science》2011,38(12):3555-3559
A paleo-parasitological study was performed on soil samples from archaeological sites in the old district of Seoul Metropolitan City (Old Seoul City) where the capital of the Joseon Kingdom was constructed about 600 years ago. The sampling sites were the original locations of the Royal Palace Wall, Yukjo Street and the Royal Arsenal. Microscopic examinations showed that parasite eggs of Clonorchis sinensis, Diphyllobothrium latum, Ascaris sp. and Trichuris sp. remained in the soil strata, which were estimated to represent the 14th-19th centuries. We suspect that the medieval citizens of Old Seoul City, numbering around 200,000, might have been made vulnerable to parasite infection by a combination of bad hygiene, inadequate sewer system and seasonal flooding. 相似文献
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基于腾讯迁徙大数据的长三角城市群春运人口流动时空特征 总被引:1,自引:0,他引:1
开展城市群人口流动研究对促进区域人口有序流动和城市群协同发展具有重要的理论和实践指导意义。本文基于腾讯迁徙大数据,运用GIS空间统计和K-shell分解等方法,从人口流动总量、位序、时序和网络层级等方面,对我国长三角城市群2018年春运期间的人口流动特征进行系统研究。结果表明:①长三角城市群春运期间大规模的“返乡流”和“返城流”呈现明显的对称性,并分别于除夕和第一个工作日达到最高峰。②经济发展水平相对较高的上海、苏州、杭州等为劳动力输入型城市,而经济发展水平相对较低的盐城、安庆和滁州等为劳动力输出型城市。③长三角城市群内部人口流动网络具有明显的层级特征,其中上海和杭州是人口辐射核心城市,上海-合肥、上海-南京、上海-杭州等是人口流动的主体路径;空间上东部-西部横向人口流动最为频繁,大体呈现“Z”字形。 相似文献