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141.
<正>The oldest representative of the genus Megarhyphus Kovalev(Diptera:Anisopodidae)is described from the Lower Jurassic(Sinemurian)of England.A summary of our knowledge of Jurassic Anisopodidae is given.  相似文献   
142.
<正>A new genus Microelectrona gen.nov.and species Microelectrona cladara sp.nov.of the extinct tribe Protodikraneurini of the leafhoppers(Cicadeilidae:Typhlocybinae) from the Eocene Baltic amber is described. The piece of amber containing leafhopper inclusion is broken,unveiling some of the morphological structures,and enabling their studies using scanning electron microscopy.  相似文献   
143.
<正>El Soplao outcrop,an Early Cretaceous amber deposit recently discovered in northern Spain (Cantabria),has been shown to be the largest site of amber with arthropod inclusions that has been found in Spain so far.Relevant data provided herein for biogeochemistry of the amber,palynology,taphonomy and arthropod bioinclusions complement those previously published.This set of data suggests at least two botanical sources for the amber of El Soplao deposit.The first(type A amber)strongly supports a source related to Cheirolepidiaceae,and the second(type B amber)shows non-specific conifer biomarkers.Comparison of molecular composition of type A amber with Frenelopsis leaves(Cheirolepidiaceae)strongly suggests a biochemical affinity and a common botanical origin.A preliminary palynological study indicates a regional high taxonomical diversity,mainly of pteridophyte spores and gymnosperm pollen grains.According to the preliminary palynological data,the region was inhabited by conifer forests adapted to a dry season under a subtropical climate.The abundant charcoalified wood associated with the amber in the same beds is evidence of paleofires that most likely promoted both the resin production and an intensive erosion of the litter,and subsequent great accumulation of amber plus plant cuticles.In addition,for the first time in the fossil record, charcoalified plant fibers as bioinclusions in amber are reported.Other relevant taphonomic data are the exceptional presence of serpulids and bryozoans on the surfaces of some amber pieces indicating both a long exposure on marine or brackish-water and a mixed assemblage of amber.Lastly,new findings of insect bioinclusions,some of them uncommon in the fossil record or showing remarkable adaptations,are reported.In conclusion,a documented scenario for the origin of the El Soplao amber outcrop is provided.  相似文献   
144.
<正>Representatives of the extinct psocid family Empheriidae are known from Eocene Baltic amber, Lowermost Eocene French amber(Oise),and Lower Cretaceous Spanish amber(Alava).We report herein the first discovery of an empheriid psocid from the Cretaceous amber of New Jersey as Jerseyempheria grimaldii gen.et sp. nov.The fossil is figured and described.The new species is distinguished from related taxa.A discussion and checklist of Empheriidae are provided.  相似文献   
145.
<正>A new genus and species of Rhachiberothidae,Raptorapax terribilissima gen.et sp.nov.from the Cretaceous amber of Lebanon is described.The new genus is assigned to the subfamily Paraberothinae.The new material confirms the great diversity of the group in the Cretaceous age and its decrease in diversity in recent times.  相似文献   
146.
A New Family of Moths from the Middle Jurassic (Insecta: Lepidoptera)   总被引:1,自引:1,他引:0  
<正>Three lepidopteran species,from the Middle Jurassic Daohugou beds(inner Mongolia,China),are described in a new family,Mesokristenseniidae,and new genus,Mesokristensenia,which could represent the sister group of the Micropterigidae.Mesokristensenia differs from all extant Lepidoptera,but one genus(Agathiphaga, Agathiphagidae),in retaining four median veins in the forewing,a plesiomorphy also present in many Trichoptera. Evidence for placing Mesokristensenia in the Lepidoptera includes four traits,notably a previously unrecorded autapomorphy of this insect order:beyond stem M1+2,vein M1 is bent and connected to cross-vein r-m(in both wing pairs).Among 24 characters taken into account to assess the systematic position of Mesokristensenia,12 are considered informative for a cladistic analysis involving this fossil taxon and the four suborders recognized in present-day Lepidoptera(Zeugloptera,Aglossata,Heterobathmiina,and Glossata).  相似文献   
147.
Cearadactylus atrox is one of the first pterosaurs unearthed from the Araripe Basin (Northeast Brazil) (Leonardi and Borgomanero 1983, 1985) (Fig.1). The fossil was preserved in a calcareous concretion typical of the Romualdo Formation and comprised an almost complete skull with lower jaw, but lacked the occipital region.  相似文献   
148.
全国土地利用格网数据生产技术方法探讨   总被引:2,自引:0,他引:2  
本文在全国多尺度土地利用格网数据需求分析的基础上,基于土地利用矢量网格化生产工程实践,分析和阐述了国家土地利用格网参数选择依据、格网内地类面积的算法、格网综合和批量化处理等主要技术方法。研究结果表明:利用本研究开发的土地利用矢量网格化软件,对县级土地利用矢量数据进行网格化处理,可快速生产合格的全国土地利用地理格网数据,并将极大的促进全国土地调查数据成果的社会化共享应用。  相似文献   
149.
Thehumandevelopmentalhistoryrevealsthatmanhasneverneglected exploitingtheundergroundspace, fromtheprimitive'caveliving' tothe'undergroundvillage' inMatermataofTunis,fromthesubsided'cavedwelling' inthenorthwestofChinatothepre-sent'undergroundcity'.Theundergroundspacehasbeenexploitedwidelyanddeeply. Thewidespreadutilization oftheurbanunder-groundspacetookplaceafter thebeginningofindus-trialrevolutionsandurbanization.Dueto seriesofproblemsonurbandevelopmentresultedfromtheoverconcentrationofpo…  相似文献   
150.
The present study describes a new genus and species Unicohormaphis sorini, which belongs to the subfamily Cerataphidinae. The contemporary distribution of aphids belonging to the Hormaphididae family is summarized and analyzed. According to the obtained data, the climate warming in Eocene was conducive to the expansion of the family over the areas of Europe. Subsequent climate changes, resulting from epeirogenic and orogenic movements towards the end of Eocene, led to a considerable cooling and drying of climate in the northern hemisphere. These processes contributed to the shrinking down of areas covered by subtropical forests, which constituted the habitat of Hormaphididae (Cerataphidinae). Retaining their way of life, the Cerataphidinae were forced to limit their distribution, and the representatives of the family in Europe became completely extinct.  相似文献   
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