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1.
记述了新疆锅底坑组的两件水龙兽标本 ,其中产自吉木萨尔县的一件层位最低 ,被鉴定为杨氏水龙兽相似种 (Lystrosauruscf.L .youngi)。在支序分析的基础上对比了中国与南非的水龙兽 ,认为两地的水龙兽大多数分别构成单系类群。总结了中国新疆水龙兽在锅底坑组和韭菜园组下部出现的层位 ,并讨论了以水龙兽来确定陆相二叠 -三叠系界线。  相似文献   

2.
The South African Plio-Pleistocene cave deposits have yielded a diverse cercopithecoid fauna. In this study, the possible dietary proclivities of these extinct species are examined using details of molar microwear. Although sample sizes are often small, wear patterns suggest possible temporal changes in the diets of Parapapio jonesi from Makapansgat to Sterkfontein, of Papio robinsoni from Sterkfontein to Swartkrans, and Cercopithecoides williamsi from Makapansgat to Sterkfontein to Swartkrans. However, there does not appear to have been a significant change in the dietary habits of Parapapio broomi over time. The microwear patterns of the two temporally successive congeners, Theropithecus darti and T. oswaldi show no significant differences from one another. The sympatric congeners, Parapapio broomi and Pp. jonesi, have microwear signatures that differ significantly at Makapansgat (Members 3 and 4) but not at Sterkfontein (Member 4). Finally, the microwear analyses suggest that the extinct cercopithecoid species did not necessarily have diets similar to those of their closest living relatives.  相似文献   

3.
Abstract:  Twenty-nine Arenig and Llanvirn trilobite species, representing 20 genera in the Asaphidae, Cyclopygidae, Dikelokephalinidae, Nileidae, Raphiophoridae, Remopleurididae, Taihungshaniidae and Trinucleidae, are treated in a taxonomic review of the South Chinese Asaphida. This review is based on large collections of trilobite material made from five formations at nine localities in western Hubei, northern Hunan and southern Shaanxi, representing a wide range of benthic marine environments across the Yangtze Platform and Jiangnan Transitional Belt regions of the South China Plate. Most South Chinese representatives of the Asaphidae are reassigned to the Nobiliasaphinae on the basis of cranidial and hypostomal characters, and taxonomic revisions are given for Liomegalaspides and Opsimasaphus pseudodawanicus . Taihungshania shui and T . tachengssuensis are revised and redescribed, and the establishment of lectotypes for these species and T . brevica clarifies the status of the type material of Taihungshania . Nileus walcotti is revised and restricted biogeographically to the South China Plate; material from Xinjiang previously assigned to this species is reassigned to N .  sericeus sp. nov. The new raphiophorid species Raphioampyx sinankylosus is described. Aocaspis , Incaia and Raphioampyx are recorded for the first time from South China, and the latter two genera are also recorded for the first time from the Arenig.  相似文献   

4.
Abstract. A survey was made of the phlebotomine sandfly fauna of La Guaira, a village with coffee plantations near Cali, Colombia, from which cases of American cutaneous leishmaniasis had been reported due to Leishmania (Viannia) panamensis and Le. ( V. ) braziliensis. Among six species of sandfly collected on human bait, Lutzomyia youngi was most important in terms of biting nuisance. Lu. columbiana, Lu. lichyi and Lu. scorzai as well as Lu. youngi adults occurred throughout the year. Sandfly man-biting activity occurred throughout the night and was highest within 2 h of sunset. Despite its abundance in nocturnal samples, Lu. youngi was rarely taken in diurnal resting site collections. In contrast, Lu. lichyi was collected on tree-trunks during the day in large numbers and was the only species biting in daylight. The implications of these and other findings for leishmaniasis control measures in La Guaira are considered.  相似文献   

5.
Cytogenetic characteristics were established for five native species of phlebotomine sand flies (Lutzomyia, series townsendi, verrucarum group): Lutzomyia longiflocosa, Lutzomyia townsendi, Lutzomyia spinicrassa, Lutzomyia torvida and Lutzomyia youngi. Karyotypes and chromosomal morphometry were compared. Using the squash technique, brain tissues from late 4th instar larvae provided the necessary mitotic chromosomes. Chromosomal measurements were made on the following chromosomal characteristics: short arm, long arm, arm ratio, total length, relative length, centromeric index and relative length average of chromosomes. Chromosomes were classified according to their morphometry and position of the centromere. The taxonomic distance was calculated, and the relationships among the species displayed in a phenogram. All five species possessed four pairs of chromosomes as diploid number (2N = 8). None of the karyotypes indicated presence of heteromorphic chromosomes. Statistical analysis of the morphometric data showed highly significant differences among the chromosomes pairs of the five species. However, the total length of the genome was very similar, with the exception of L. youngi. In conclusion, these closely related species were distinguishable at cytological level.  相似文献   

6.
自1978年以来作者比较系统的进行了中国灵芝科(Ganodermataceae)的分类研究。于1981年“中国灵芝”一书中报道了53种1变种和1变型。除前两个种下分类单位已承认为种外,后又陆续报道了30种。目前共报道了中国灵芝科85种。随着各国专家对灵芝科分类研究的不断进展,对于过去记载的种类,其中一部分种类已进行了考证,重新作了订正,作者也正在对中国灵芝科的种类进行订正。参考了Steyaert(1980)和Corner 1983)以及其他作者的重要文献,对现有8种进行了订正。本文共报道11种,其中有3新种。它们是坝王岭灵芝(Ganoderma bawanglingense Zhao et X.Q.Zhang),江西假芝(Amauroderma jiangxiense Zhao et X.Q.Zhang)和五指山假芝(A.wuzhishanense Zhao)。本文研究标本全部保藏于中国科学院微生物研究所真菌标本室。  相似文献   

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The value of Colombian phlebotomine eggs for species determination was studied with a scanning electron microscope. The species diversity and medical importance of the verrucarum group were the bases to select Lutzomyia youngi, Lutzomyia evansi, Lutzomyia columbiana and Lutzomyia longiflocosa. The egg surface was poligonal. Lutzomyia youngi, and Lutzomyia columbiana had pentagonal or hexagonal patterns; Lutzomyia evansi elongated polygons and Lutzomyia longiflocosa irregular polygonal sculpturing, frequently rectangular. Egg scanning electron microscopy is reliable to identify species of the verrucarum group.  相似文献   

10.
为了解南海栉江珧(Atrina pectinata)的群体遗传变异特征, 研究利用线粒体DNA COⅠ(细胞色素氧化酶亚单位Ⅰ)基因部分序列对7个群体共191个栉江珧个体进行群体遗传多样性和遗传结构分析。结果显示: 在600 bp长的序列中, 共检测到113个核苷酸变异位点, 定义了73个单倍型。南海北部栉江珧总体呈现较高的单倍型多样性(0.8996)和较高的核苷酸多样性(0.0257), 但L1组内6个群体(汕头、阳江、湛江、海口、琼海、北海)呈现较高的单倍型多样性(0.8133—0.9286)和较低的核苷酸多样性(0.0033—0.0045)。单倍型系统发育树和网络支系图将7个群体划分为L1和L2(防城港群体)两大类群, 但L1组单倍型并未表现出与地理位置相对应的谱系结构。Fst分析显示, L1组内6个群体间不存在明显的遗传分化(Fst= –0.0200— –0.0055, P>0.05), 但L1组与L2组间存在极显著的遗传分化(Fst=0.8729—0.8821, P<0.01)。L1组的Tajima’s D检验(D= –2.3190, P=0)和Fu’s Fs检验(Fs=–26.8316, P=0)均为显著负值, 核苷酸不配对分布呈明显的单峰分布; L2组的Tajima’s D检验(D=–1.4320, P=0.0565)为不显著负值, Fu’s Fs检验(Fs=4.9540, P=0.9620)为不显著正值。以上数据说明, L1组和L2组栉江珧可能已经分化为两个群体, L1组内6个群体具有频繁的基因交流, 导致了较高的遗传同质性。  相似文献   

11.
方芳 《动物分类学报》2000,25(2):214-227
中国Dan属鱼类共有7种,分布于云南南部和西南部的三大流域中。其中半线Dan Daio interrubtus,红蚌Dna D.kakhienensis,缺须Dan D.apogon和珍珠Dan D.albolineatus分布地伊洛瓦底江流域的大盈江和龙川江水系,布良Dan D.browni和撞邦Dan.D.shanensis分布于萨尔温江上游的怒江水系,金线Dan D.chrysotaenia  相似文献   

12.
The abaxial and adaxial epidermis of young and mature leaves of the South American species of Chenopodium L. (Chenopodiaceae) have mucilage secreting glandular structures that have not been reported in previous studies, either for the Chenopodiaceae or other Phanerogamic taxa. Their morphology and function have been studied and all stages of their ontogenic pathway have been described and illustrated. The name ‘glandular mucilagene surface’ is proposed. Their adaptative value is discussed and differences from other leaf epidermal differentiations are noted. These structures have been discovered in Chenopodium species living in Patagonia, their presence in all South American species — native and exotic ones — of the genus has been investigated and proved. The possibility that it could be a generic feature is suggested.  相似文献   

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Liu JX  Chen HY  Xu ZF 《ZooKeys》2011,(108):49-60
The Chinese species of the genus Ismarus Haliday, 1835, are revised for the first time. Three new species from the Oriental region of China and belonging to Ismarus halidayi-group are described and illustrated: Ismarus longussp. n., Ismarus nigritrochantersp. n. and Ismarus parvicellussp. n. Two species are newly reported for the Chinese fauna: Ismarus dorsiger (Haliday, 1831) and Ismarus halidayi Foerster, 1850. A key to the Chinese species of the genus is provided. The type specimens are deposited in the Hymenopteran Collection of South China Agricultural University, Guangzhou (SCAU).  相似文献   

15.
壳斗科植物摘录(Ⅱ)   总被引:2,自引:1,他引:1  
黄成就  张永田   《广西植物》1988,(1):1-42
本文报道柯属Lithocarpus Bl。的新分类群,即17新种,7新变种,新名3,新组合5,对少好的种作了订正。属的中名取名为柯,并作简要的讨论。又文内提到的绝大多数的新种,早在1982年出版的《中国高等植物图鉴》补编Ⅰ里用分种检索的形式作了初报,但全部都是裸名。此外,尚有个别种更改其等级或归并。 本文引用的标本,除属华南植物研究所SCBI外均注明标本的保存单位(标术室缩写代号见植物分类学报20(2):252—256,1982)。  相似文献   

16.
Two new species of Leptobotia are here described as L. rotundilobus from the Xin'an-Jiang of the upper Qiantang-Jiang basin in both Anhui and Zhejiang Provinces and the Cao'e-Jiang in Zhejiang Province, and L. paucipinna from the Qing-Jiang of the middle Chang-Jiang basin in Hubei Province, South China. Both have a plain brown body as found in L. bellacauda Bohlen & Šlechtová, 2016, L. microphthalma Fu & Ye, 1983, L. posterodorsalis Chen & Lan, 1992 and L. tientainensis (Wu, 1930). The two new species are distinct from these species in vertebral counts, further from L. posterodorsalis in vent placement and further from the other three species in pectoral-fin length. Both differ in caudal-fin coloration and shape, and dorsal-fin location and coloration, and also in internal morphology. Their validity is confirmed by their own monophyly recovered in a phylogenetic analysis based on the mitochondrial cyt b and COI genes.  相似文献   

17.
The genus Lycoseris is revised to include eleven species of dioecious subshrubs with mostly scrambling branches. It is distributed from Guatemala to northwestern and western South America, reaching south to Bolivia and southern Brazil. Three new species are described, viz. L. colombiana, L. minor , and L. peruviana. One new combination is made, viz. L. trinervis ssp. altissima.  相似文献   

18.
Morphological variation among populations of Leporinus friderici (Bloch), an anostomid fish of widespread neotropical distribution, has been hypothesized but never conclusively demonstrated. We used multivariate procedures to examine patterns of morphometric variation among populations of L. friderici from three South American biogeographic regions: the Paraná-Paraguay River and Amazon River basins of Brazil, and the Marowijne River basin of Suriname. Samples from the southern Paraná-Paraguay basin are completely distinct from the northern Amazonian and Suriname regions in principal components analysis, primarily on the basis of body elongation and orbit differcnces. Samples from the two northern regions were separated in a size-free canonical variates analysis by differences in relative body depth. These results emphasize a need for further studies of neotropical fish species with similar distribution patterns.  相似文献   

19.
2002至2019年对广东、广西和海南主要森林生态系统的72个保护区、森林公园、植物园、公园和林场等的多孔菌进行了采集和调查,共采集标本2 095号,经对这些材料全面和系统的研究,发现多孔菌500种,按照最新的系统学研究分属于8个目、20个科、145个属,其中多孔菌科和锈革孔菌科分别有173种和124种,约占总数的60%,是最重要的多孔菌类群。此外,其中有10个新属和132个新种是作者等人根据华南地区模式标本发现描述的。本文对华南地区多孔菌多样性进行了系统归纳,按最新的分类系统以属名顺序给出了名录,根据采集材料提供了每种的生长基质,并对所有种类的生长基质习性进行了统计。其中,294、138、112、97、78、77和29种分别生长在倒木、落枝、朽木、死树、活立木、树桩、掉落小枝和地上,故倒木是多孔菌最重要的生长基质。  相似文献   

20.
Different frameworks have been proposed for using molecular data in systematic revisions, but there is ongoing debate on their applicability, merits and shortcomings. In this paper we examine the fit between morphological and molecular data in the systematic revision of Paroaria, a group of conspicuous songbirds endemic to South America. We delimited species based on examination of >600 specimens, and developed distance-gap, and distance- and character-based coalescent simulations to test species limits with molecular data. The morphological and molecular data collected were then analyzed using parsimony, maximum likelihood, and Bayesian phylogenetics. The simulations were better at evaluating the new species limits than using genetic distances. Species diversity within Paroaria had been underestimated by 60%, and the revised genus comprises eight species. Phylogenetic analyses consistently recovered a congruent topology for the most recently derived species in the genus, but the most basal divergences were not resolved with these data. The systematic and phylogenetic hypotheses developed here are relevant to both setting conservation priorities and understanding the biogeography of South America.  相似文献   

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