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31.
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
32.
A new polypore fungus beetle is described and illustrated, under the name of Thescelostrophus cretaceus gen. et sp. nov., representing the first documented occurrence of the tribe Eustrophini. The well-preserved specimen was collected from the Upper Cretaceous (Cenomanian, ca. 99 Ma) amber near the Hukawng Valley of northern Myanmar. This fossil species can be assigned to the extant subfamily Eustrophinae based on its elongate oval and strongly narrowed posteriorly body, simple and narrow tarsi, and somewhat clubbed antennomeres. The comparison among the extinct and extant eustrophines supports the previous hypothesis that antennal morphology of early eustrophines was very diverse. Additionally, an overall similarity between Thescelostrophus and extant eustrophines suggests a potential fungivory of this fossil species. Morphological characters preserved in the Burmese amber highlight the diversity of tetratomids during the Late Mesozoic and provide data for future phylogenetic studies of Tetratomidae. 相似文献
33.
Two new genera with two new species in Berothidae, Maculaberotha nervosa gen. et sp. nov. and Magniberotha recurrens gen. et sp. nov., are described from Upper Cretaceous Myanmar (Burmese) amber. Based on the new specimens of the same species, we propose some venational characters as intraspecific variations, e.g., the markings on the wings and crossveins in the radial sector. We also study and compare the female genital sclerites from three genera of Haploberotha, Dasyberotha, and Jersiberotha to highlight the importance of using these characters preserved in amber for taxonomic and phylogenetic studies. Furthermore, an updated key to the berothid genera of Myanmar amber is provided. 相似文献
34.
The genus Mesosticta Huang, Azar, Cai et Nel, 2015 was established based on the wing bases of two damselflies from mid-Cretaceous Burmese amber. Here we describe a new well-preserved platystictid damselfly, Mesosticta electronica sp. nov., with complete forewings and hindwings. The diagnosis of Mesosticta is revised and augmented in this paper. Mesosticta electronica sp. nov. differs from Mesosticta burmatica Huang, Azar, Cai et Nel, 2015 in having the arculus slightly distal of Ax2, a free subdiscoidal cell, the hindwing AA ending on the middle area of the posterior side of the discoidal cell, and the base of RP2 being three or four cells distal of the subnodus. The new discovery adds to the diversity of damselflies in mid-Cretaceous Burmese amber and puts the origin of Platystictidae to at least the mid-Cretaceous. 相似文献
35.
Helius alavensis sp. nov., one of the oldest representative of the genus Helius Lepeletier and Serville, 1828 (Diptera: Limoniidae), is described from the Álava amber (Lower Cretaceous, upper Albian), northern Spain. This is the first representative of the subfamily Limoniinae and of the genus Helius described from this fossil resin. 相似文献
36.
A remarkable new wasp of the superfamily Evanioidea (Apocrita: Evaniomorpha) is described and figured from a female preserved in mid-Cretaceous amber from the Hukawng Valley of northern Myanmar. Othniodellitha mantichora Engel and Huang, gen. et sp. nov., is characterized by its unique combination of primitive and derived features in mesosomal and metasomal construction and wing venation, along with its peculiarly blocky head with a prominent facial horn, clypeal projection, and massive, squared mandibles, among other traits. The genus is placed in the new family, Othniodellithidae Engel and Huang, fam. nov., and is among the lower Evanioidea and distinguished from the Praeaulacidae and other Mesozoic evanioid families. 相似文献
37.
以中国西南重要的国际河流澜沧江为研究对象,借鉴"基尼系数"的构建思路,建立了水沙年内分配均匀度计算模型,并通过下游水沙与上游天然水沙和区域降水的关系,建立了河流水沙年内分配均匀度回归还原模型。还原结果与实测对比表明:漫湾、大朝山电站建设以来,澜沧江径流年内分配均匀度年均升高1.14%,变幅在-7.32%~10.81%之间,输沙年内分配均匀度年均降低0.23%,变幅在-18.98%~26.76%之间;漫湾、大朝山电站同时运行期间,澜沧江径流年内分配均匀度年均升高3.90%,输沙年内分配均匀度年均降低0.42%;大朝山水电站建设后,澜沧江径流年内分配均匀度升高而输沙年内分配变化不明显,说明大朝山水电建设后河流水沙关系发生了变化,但变化较小。该成果不仅能为相关研究提供方法借鉴,也为水电开发对澜沧江水沙年内分配影响程度的科学评估提供了新的依据。 相似文献
38.
Dany AZAR Raymond GèZE Antoine El-Samrani Jacqueline Maalouly André NEL 《《地质学报》英文版》2010,84(4):977-983
<正>Reports of amber predating the Lower Cretaceous are unusual and scarce;they mostly refer to amber pieces of millimetric dimension.In the present study,we report the discovery of 10 new outcrops of Jurassic amber in Lebanon.Some of these had large centimetric-sized pieces of amber.The new localities are described,amber is characterized,and its infrared spectra given.Although the new Jurassic amber yielded to date no more than fungal inclusions,this material is significant and promising.The discovery of several Jurassic outcrops provides crucial information on the prevailing paleoenvironment of that time. 相似文献
39.
40.
在琥珀热处理实验研究的基础上,采用常规宝石学方法和红外光谱仪,测试并跟踪收集和对比分析了实验样品热处理前、后的宝石学参数和红外光谱的变化规律及琥珀内含物的演化、改造与破坏标识,并对获得的琥珀热处理效果进行了成因分析,从而总结出鉴定琥珀热处理的关键证据。研究结果表明:(1)折射率的增加、荧光的弱化或湮灭是热处理琥珀的重要佐证;(2)盘状裂隙、红色流纹、汽化纹、龟裂纹和氧化裂纹是热处理琥珀的重要标识;(3)FTIR光谱中I=2930cm-1/I=1735cm-1比值若≤1,可视为热处理琥珀的红外光谱指纹检测依据;(4)1735,1700cm-1处的羰基(C?O)伸缩振动与1260~1156cm-1处的C—O伸缩振动吸收强度的明显增强及多峰合并的趋势反映出热处理琥珀表面的热氧化反应;C?O浓度的增加可能是热处理琥珀红色的生色团,同时又是热处理琥珀荧光的淬灭剂。 相似文献