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New data and records of the genus Chrysotoxum Meigen, 1803 are reported, arising from taxonomic and faunistic examination of adult specimens collected from 1920 to 2011 from four northeastern provinces of Turkey (Erzurum, Bayburt, Kars, and Artvin), and from the neighboring countries of Armenia, Azerbaijan and Iran. Three new species are described: Chrysotoxum antennalis Vuji?, Nedeljkovi? &; Hayat sp. n., C. clausseni Vuji?, Nedeljkovi? &; Hayat sp. n. and C. persicum Vuji?, Nedeljkovi? &; Hayat sp. n. The first two are known only from northeastern Turkey, and the third also occurs in Armenia, Azerbaijan and Iran. These new species have in common an antenna with the basoflagellomere being shorter than the scape and pedicel together.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:4C264678-8E47-4DE0-AC7D-91DABC597BCD  相似文献   
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豫东平原杨\|农复合系统凋落物的数量、组成及其动态   总被引:3,自引:0,他引:3  
万猛  田大伦  樊巍 《生态学报》2009,29(5):2507-2513
农林复合系统的凋落物既是维持植被系统和土壤系统养分循环的关键,也是维持农林复合系统结构和功能的重要因子.通过对豫东平原农区4年生、9年生和12年生3个不同林龄杨-农复合系统杨树凋落物的数量、组成及季节动态的研究来为深入研究农林复合系统对大气中CO2的调节作用以及碳循环机理提供参考数据.结果表明,4a杨-农复合系统年凋落物总量为11 18 t·hm-2;9a杨-农间作复合系统年凋落物总量为12.86 t·hm-2;12a杨-农复合系统年凋落物总量为13.75 t·hm-2.3个不同林龄的杨-农复合系统凋落物总量月变化模式较为相似,均在8月和11月份出现峰值,而以11月份数量最大.其季节变化模式则为秋季>冬季>夏季>春季.  相似文献   
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East Asian species of the genera Hybrizon and Ghilaromma are reviewed. Four species of Hybrizon, H. buccatus (Brébisson 1825), H. ghilarovi Tobias, 1988, H. juncoi (Ceballos 1957) and H. flavofacialis Tobias, 1988 and two species of Ghilaromma, G. orientalis Tobias, 1988 and G. ussuriensis Tobias, 1988, were recognized. H. ghilarovi was recorded from Korea, Japan and China, while H. juncoi was recorded from Korea, for the first time. The specimens recorded from Japan as G. fuliginosi (Wilkinson, 1930) by Watanabe (1984) are referred to G. orientalis herein. This species is newly recorded from Korea and Japan. Keys to East Asian species of Hybrizon and the world species of Ghilaromma are also provided.  相似文献   
6.
魏偏偏 《人类学学报》2020,39(4):616-631
1960年,在云南省丽江市发现了三根古人类股骨,通过地层观察,仅PA108可归为更新世晚期。前人对PA108做了初步报导,为了进一步了解丽江人股骨的演化分类地位和东亚早期现代人股骨形态变异,本文对PA108的内外结构进行了详尽的分析。研究发现,PA108具有明显的早期现代人特征,即明显的股骨粗线、骨干中部后侧骨密质最厚和中部横断面轮廓形状偏椭圆。PA108标本也有一定的特殊性,体现在骨干中近端和中部骨密质厚度分布上,这可能与其股骨嵴发育较弱有关,这一特征也导致了PA108与其他东亚早期现代人之间的形态差异,这些形态变异进一步扩大了目前已知的东亚地区早期现代人变异范围。同时,在采用骨密质厚度分布模式进行分类时,建议关注股骨骨干中部骨密质最厚部位。  相似文献   
7.
We developed nine new microsatellite markers for the white mangrove (Laguncularia racemosa C.F. Gaertn.), a mangrove species widely distributed in the Western Hemisphere. The loci were developed from a sample collected in Baja California Sur, Mexico, and were screened for polymorphism in 108 individuals from the Pacific Coast of Mexico and Costa Rica. The level of polymorphism was relatively low, from two to four alleles. These are the first set of polymorphic markers described for L. racemosa and should be of value in studying regional genetic differentiation among natural populations of this species.  相似文献   
8.
东海低氧区及邻近水域浮游植物的季节变化   总被引:11,自引:0,他引:11  
赵其彪  孙军  李丹  宣基亮 《生态学报》2015,35(7):2366-2379
根据2011年5月、8月、11月在东海低氧区及邻近水域(25°00'—33°30'N,120°00'—127°30'E)进行的多学科综合调查,对东海低氧区及邻近水域浮游植物群落结构特征及季节变化进行了相关研究。经Utermhl方法初步分析共鉴定出浮游植物4门74属248种(含变种、变型,不含未定种),主要由硅藻和甲藻组成,此外还有少量的金藻和蓝藻。春季优势种主要为具齿原甲藻(Prorocentrum dentatum)、柔弱伪菱形藻(Pseudo-nitzschia delicatissim)、骨条藻(Skeletonema sp.)和具槽帕拉藻(Paralia sulcata);夏季主要是中肋骨条藻(Skeletonema costatum)和海链藻(Thalassiosira sp.);秋季主要是具槽帕拉藻、圆筛藻(Coscinodiscus sp.)和柔弱伪菱形藻。调查区浮游植物平均细胞丰度在夏季最高,达到85.002×103个/L,春季次之,秋季最低。在水平方向上,春、夏两季,表层浮游植物细胞丰度在近岸出现高值,由近岸到外海细胞丰度逐渐降低;而在秋季则相反,在调查海域的东北部出现高值,随离岸距离的增加细胞丰度逐渐增加。在垂直方向上,春、夏两季,浮游植物细胞丰度在表层出现最大值,随着深度的增加细胞丰度逐渐降低;而在秋季细胞丰度分布比较均匀,随水深变化不明显。调查区表层浮游植物ShannonWiener多样性指数和Pielou均匀度指数的平面分布基本一致,并且与细胞丰度的分布大致呈镶嵌分布。调查浮游植物群落的演替规律是:从春季的甲藻(具齿原甲藻、微小原甲藻(Prorocentrum minimum)等)为主,硅藻(柔弱伪菱形藻、骨条藻等)为辅;演替至夏季的硅藻(中肋骨条藻、海链藻等)为主,甲藻(主要是梭状角藻(Ceratium fusus)和叉状角藻(Ceratium furca))为辅,到秋季进一步演替为硅藻(具槽帕拉藻、圆筛藻、柔弱伪菱形藻等)为主,铁氏束毛藻(Trichodesmium thiebaultii)为辅。浮游植物物种组成、优势种、细胞丰度及多样性指数均表现出明显的时空变化。低氧区与非低氧区浮游植物群集存在明显差异。  相似文献   
9.
Most of the population of Eastern Europe inhabit an area of great anthropological interest, because of the contact between Caucasoid and Mongoloid anthropological types. We have analyzed normal variability in minisatellite and microsatellite loci in some East European population. Different synthetic maps were constructed using reliability theory to evaluate the degree of accuracy. Comparison of the synthetic maps for DNA with classical markers has revealed a high level of correlation. All the data obtained show the diverse influence of both anthropological types in forming the gene pool of the Eastern European peoples.  相似文献   
10.
The persistence of species taxa within fragmented habitats is dependent on the source–sink metapopulation processes, and forest patch size and isolation are key factors. Unveiling species–patch area and/or species–patch isolation relationships may help provide crucial information for species and landscape management. In this study, relationship between forest patch size and isolation with abundance and occupancy probability of forest-dependent birds was investigated. This study was based within a coastal landscape that faces deleterious human activities such as clearing for agriculture. The study aimed to answer the question of whether the size and extent of isolation of forest patches influence abundance and/or occupancy probability of forest-specialist and generalist birds. Two bird species, namely Tiny Greenbul Phyllastrephus debilis subsp. rabai and Yellow-bellied Greenbul Chlorocichla flaviventris, were used as models. Birds were surveyed using distance sampling methods, and spatial metrics were measured from satellite imagery. Focal forest size and distance between forest patches were the most influential metrics whereby abundance and occupancy probabilities increased with increasing patch size, but were negatively influenced by increasing gaps between patches. These findings provide evidence of the existence of patch size/ isolation–occupancy relationships characterised by higher occupancy rate of large patches and distance-dependent dispersal, which decreased with increasing gaps between patches. Controlling deleterious human activities that reduce forest size should be a priority for the long-term conservation of forest-dependent birds.  相似文献   
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