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21.
X-ray microcomputed tomography was used to reveal putative trematode metacercariae (Platyhelminthes: Digenea) located in cysts positioned at the base of the femora in a 100 myr agamid lizard preserved in Myanmar amber. The cysts are characterized and compared with encysted metacercariae recovered from a similar location in an extant Anolis lizard. This discovery provides evidence that lizards were serving as intermediate hosts of trematodes some 100 Ma. 相似文献
22.
A second species of the extinct scydmaenine genus Cretoleptochromus Cai & Huang, C. burmiticus sp. nov., is described and figured based on three exquisitely preserved specimens embedded in mid-Cretaceous Burmese amber. The new taxon possesses an extremely elongate body form and strongly extended legs and antennae that provide reliable means for species diagnosis and a ready separation from the only known congener, the type species C. archaicus Cai & Huang, also reported from Burmese amber. The morphology of C. burmiticus also suggests that this species was probably an active diurnal predator living in open environments. 相似文献
23.
A new species of Glaesoconis Meinander (Neuroptera: Coniopterygidae) from the Santonian Taimyr amber
Glaesoconis popovi sp. nov. (Neuroptera: Coniopterygidae) is described from Upper Cretaceous (Santonian) Taimyr amber of northern Siberia (Yantardakh locality). The new species may be distinguished from others in the genus by much smaller eyes and the shape of the terminal segment of the maxillary palpus. The generic affinity of Glaesoconis baliopteryx Engel, 2004 from the mid-Cretaceous Burmese amber needs confirmation. 相似文献
24.
Fossil leiodids are sparse, and they are confined to the Cenozoic. Here we describe and illustrate the first definitive Mesozoic leiodid, Colonellus burmiticus sp. nov., based on two well-preserved adults from the Upper Cretaceous Burmese amber. The fossil is firmly placed in the extant Coloninae based on multiple synapomorphies, such as antennae with normal-sized antennomere 8 and abdominal intersegmental membranes with “brick-wall” pattern. It can be further assigned to the extant genus Colonellus (subgenus Pentacolonellus) by its five-segmented antennal club. The discovery suggests that Colonellus is an ancient group, originating no later than the mid-Cretaceous. 相似文献
25.
The dysagrionid damselflies are relatively diverse in Burmese amber, with two genera already recorded. A new dysagrionid damselfly, Electrodysagrion lini Zheng, Nel and Wang, gen. et sp. nov., corresponding to the oldest record of the tribe Dysagrionini, is described herein. It has the unique ‘sieblosiid-dysagrionine’ type of discoidal cell. It differs from other genera of Dysagrionini in having no antenodal crossveins distal of Ax2, Arc aligned with Ax2, and only one row of cells in the cubito-anal area below the nodus. This find puts the origin of Dysagrionini back to at least the mid-Cretaceous. 相似文献
26.
目前市场上仿琥珀产品很多,对其鉴别较困难。通过放大检查琥珀与仿琥珀塑料样品的包裹体与外部特征,结果发现,两者存在较多的差异,如蜜蜡与仿蜜蜡塑料的条纹、爆花琥珀与仿爆花琥珀塑料的裂隙盘、植物珀与仿植物珀塑料的植物枝节特征、虫珀与仿虫珀塑料的昆虫特征等,这些均可用于鉴别琥珀与仿琥珀塑料。 相似文献
27.
28.
Fossil smicripid beetles are very rare. Here we describe and figure the first Mesozoic representative of Smicripidae. Smicrips cretacea sp. nov., a new species belonging to the extant Smicrips LeConte is preserved in the Upper Cretaceous amber from northern Myanmar. Our discovery suggests that Smicrips is an ancient group, originating at least in the earliest Late Cretaceous. Together with other two fossil Smicrips species from the Eocene of Europe, it reinforces the hypothesis that the Recent distribution of Smicripidae is relict, and the family was more widespread in the Mesozoic and early Cenozoic than it is in the Recent. 相似文献
29.
A new brachyceran fly (Diptera: Tabanomorpha), Pseudorhagio zhangi gen. et sp. nov., is described from Late Cretaceous Burmese amber. It is tentatively placed as Family incertae sedis in Tabanomorpha and distinguished from other Tabanomorpha by the following unusual combination of characters: head wider than thorax; body densely covered with fine and short setae, devoid of macrosetae; scutum strongly convex, nearly spherical; scutellum rather small, convex; antennal flagellum elongated, tapering, unsegmented; vein R4 perpendicular to R5, and strongly curved; crossvein m-m very long, strongly sinuated; tibial spur formula 0, 2, 0. This discovery further confirms the high diversity of Tabanomorpha in Late Cretaceous Burmese amber. An updated list of brachyceran species in Burmese amber is given. 相似文献
30.
A new subfamily, Burmadysagrioninae Zheng, Wang and Nel, subfam. nov., for the genus and species Burmadysagrion zhangi Zheng, Wang and Nel, gen. et sp. nov. is described from mid-Cretaceous Burmese amber. This is the third dysagrionid damselfly from the Mesozoic and the second one from Burmese amber. The new specimen has a unique discoidal cell with the anterior and posterior sides not parallel, and the basal side longer than the distal side, unlike the typical ‘sieblosiid-dysagrionine’ type. It differs from other dysagrionid damselflies by the presence of a simple wing venation, the vein IR1 originating below the pterostigma and a special discoidal cell. 相似文献