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101.
<正>Arthropodan syninclusions in the Late Eocene Rovno amber were examined using x~2 to reveal correlation of the component groups(some taxa of Diptera,ants,aphids,and mites) supposedly indicative of the biocoenotic relationships in the ancient amber forest.Three tightly correlated groups were identified,representing a putative aerial plankton guild(Chironomidae+Ceratopogonidae) and two tree-trunk guilds,one of which (Dolichopodidae+Germaraphis) is possibly connected to more open or/and more hygrophilous habitats than the other(Sciara zone Diptera +"Acarus"rhombeus).The ants were not linked with any of the above components.  相似文献   
102.
New Taxa of Chrysomelidae (Insecta:Coleoptera)from Rovno Amber,Late Eocene   总被引:1,自引:1,他引:0  
<正>Leaf beetles Chrysomelidae of Rovno amber,from the Late Eocene,are recorded and described. Chrysomelidae of Rovno amber are represented by three subfamilies:Galerucinae(Alticini),Chrysomelinae,and Eumolpinae.Two new genera and three new species of Alticini:Manobiomorpha Nadein,gen.nov.(type species Manobiomorpha eocenica Nadein,sp.nov.),Psyllototus Nadein,gen.nov.(type species Psyllototus progenitor Nadein,sp.nov.),and Crepidodera decolorata Nadein et Perkovsky,sp.nov.are described.A new chrysomeline genus and species Paleophaedon minutus Nadein gen.nov.et sp.nov.is described.Probable trophic association of Crepidodera decolorata sp.nov.,the taxonomic positions of Manobiomorpha gen.nov.and Psyllototus gen.nov., and the composition of leaf beetle faunas of Middle and Late Eocene of Europe are discussed.  相似文献   
103.
<正>A new fossil chironomid,Tanytarsus serafini,found in Baltic amber is described and illustrated based on adult males.The new species and similar extant species of the genus Tanytarsus van der Wulp are compared. Due to several distinct characters of wing,legs and hypopygium,a new species group for Tanytarsus serafini is proposed,and its diagnostic features are evaluated.  相似文献   
104.
<正>Aphids are marked by their high polymorphism,but species reported from the Early Cretaceous are known only from alate morphs.The discovery of an apterous adult morph in Lebanese amber and a larva of the same species are very important for the understanding of both the morphological and biological evolution of this insect group at the very early stage of development.Gondvanoaphis estephani new subfamily,new genus and species of the recent aphids family Thelaxidae is described.The characters of the new genus in respect to other genera placed in Thelaxidae are reviewed.The palaeoecological and palaeogeographical data concerning Gondvanoaphis new genus are also discussed.  相似文献   
105.
P. Nel  D. Azar  A. Nel   《Cretaceous Research》2007,28(6):1033-1038
A new family of thrips, Moundthripidae, is described on the basis of a new genus and species, Moundthrips beatificus, from Early Cretaceous Lebanese amber. This taxon has plesiomorphic prognathous mouthparts, a unique type of wing venation and the main apomorphies of the Thysanoptera of the legs and mouthpart structures, suggesting that they were acquired very early during the evolution of this order.  相似文献   
106.
本文介绍了射线法CT 层析成象的基本原理,利用代数重建法进行图像重建的方法及在 IBM—PC微机上实现该算法的途径和框图。文章还讨论了影响图象质量的因素和处理方法。  相似文献   
107.
A peculiar new lineage of sawflies (‘Symphyta’) is described and figured from a female beautifully preserved in Upper Cretaceous (Cenomanian) amber from northern Myanmar. Syspastoxyela rhaphidia Engel and Huang, gen. et sp. nov., shares many plesiomorphic features with the primitive Xyelidae, 2Xyelotomidae, and 2Xyelydidae such as enlarged and thickened first flagellomere succeeded by a series of thinner and shorter flagellomeres, absence of a transverse mesoscutal sulcus, multiple preapical spurs, and two protibial spurs among other traits. However, the new lineage has an apomorphically contracted forewing venation, lacks a subcostal vein, has a single marginal cell, and lacks crossvein 1r-rs, and thus it is segregated into a new family, Syspastoxyelidae Engel and Huang, fam. nov. The phylogenetic affinities of the new family are discussed and a position near Pamphilioidea or Pamphilioidea + Unicalcarida is advocated.  相似文献   
108.
A new polypore fungus beetle is described and figured from an individual preserved in Upper Cretaceous (Cenomanian, ca. 99 Ma) amber from northern Myanmar. Cretosynstrophus archaicus gen. et sp. nov. is confidently placed in the extant subfamily Eustrophinae based on its elongate oval body and pronotum with two basal, sublinear impressions. It shares several characters belonging to two Recent tribes (Eustrophini and Holostrophini), but it cannot be attributed to either of them. Together with other tetratomid genera from the Cretaceous, the new discovery implies that the Recent small family Tetratomidae is much more diverse and more widespread than previously documented. In addition, a morphological similarity between Cretosynstrophus and extant Synstrophus suggests a similar fungi feeding habit for Cretosynstrophus, highlighting an ancient association between tetratomid beetles and fungi in the Mesozoic.  相似文献   
109.
Two new genera and species belonging to the family Scolebythidae are described from mid-Cretaceous amber of Myanmar, Cursoribythus silvestris and Siccibythus musculosus. These taxa are introduced into the current phylogenetic tree of the family, in order to analyze their relationships and observe their impacts on our understanding of the family. The implication of the findings (this is the first record of the family in the Cretaceous amber deposits of Myanmar) are discussed.  相似文献   
110.
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