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51.
Because of possible variation in venom composition, an understanding of venomous snake systematics is of great importance for the optimization of antivenom treatment of snakebite patients. Intraspecific variation in the morphology of many venomous snakes complicates the definition and indentification of some species when allopatric populations are involved. Selectively neutral or near-neutral mtDNA sequences can reveal evolutionary relationships obscured by ecogenetically-caused morphological variation. We use comparative sequencing of the cytochrome oxidase subunit 1 gene to reveal the existence of a widespread, cryptic species of spiting cobra from southeast Asia. This species,Naja siamensis, is widely sympatric with other Asiatic cobra species. This may be of considerable medical significance, and calls for further research into venom composition in Asiatic cobras. 相似文献
52.
:固体地球化学中常用的Pb Pb和Rb Sr同位素方法被用于测定石油生成、运移的年龄。对准噶尔盆地乌尔禾沥青脉、塔里木盆地志留系固体沥青的Pb Pb和Rb Sr同位素年龄测定表明 ,油气生成、运移均与重大地质事件有关 ,这种方法可以用来测定石油生成、运移的年龄 ,从而解决了石油生成机制、运移动力等研究难题。说明用固体金属同位素定年方法可以解决石油地质的重大问题 相似文献
53.
李仕成 张玉虎 周小红 石跃 柳敏良 方永得 王建国 KIMURA A HATSUKAWA Y HAYAKAWA H SHIZUMA T KATAKURA J MATSUDA M MORIKAWA T SUGAWARA M KUSAKARI H 《中国科学:物理学 力学 天文学》2012,(10):1062-1075
利用重离融合蒸发反应和在束γ谱学验方法,研究了双奇核186Au的高旋态能级结构.扩展了186Au核基于πh9/2i13/2和πi13/2i13/22-准粒组态的转动带能级纲图,并重新指认了两条转动带的能级旋值,发现两条转动带在低旋区均出现旋称反转.系统地分析了Au同位素双奇核πh9/2i13/2,πi13/2i1/3和πh-111/2-νi-1312转动带的旋称劈裂特征.本工对186Au核πh-111/-2νi-132/2j(j=p3/2,f5/2)转动带(17+)态之上能级结构了修改.根据验提取的准粒顺排角动量以及对Au双奇核带结构的系统性比较和分析,别出了一条组态为πh-111/-2νi-1322h-19/2的扁椭球转动带. 相似文献
54.
55.
Omar Torres-Carvajal Fernando P. Ayala-Varela Simón E. Lobos Steven Poe Andrea E. Narváez 《Journal of Natural History》2018,52(13-16):1067-1089
ABSTRACTWe describe two new species of Anolis lizard that are sympatric on the Amazonian slopes of the Andes of southern Ecuador at elevations between 1440 and 1970 m. The new species may be distinguished from other Anolis by external anatomy, mitochondrial divergence and dewlap colour. We estimate the phylogenetic positions of the new species using Bayesian analysis of DNA sequence data including all species of Dactyloa-clade Anolis for which DNA data are available. Anolis hyacintogularis sp. nov. is sister to Anolis calimae, whereas Anolis lososi sp. nov. is sister to Anolis williamsmittermeierorum, herein reported for Ecuador for the first time. Individuals of both new species were collected within a protected area in southern Ecuador, Podocarpus National Park, which suggests that at least some populations of these species are well protected.www.zoobank.org/urn:lsid:zoobank.org:pub:E55FA804-E3FD-4412-8FEB-5234E29E272D 相似文献
56.
《Journal of Natural History》2012,46(41-44):2569-2620
The aim of this paper is to revise populations of Macrothrix cf. hirsuticornis (Cladocera: Anomopoda: Macrothricidae) from different regions of the southern hemisphere. It is demonstrated that M. hirsuticornis Norman and Brady, 1867 s. str. is absent there, and five related species occupy different Subantarctic islands and the southernmost portions of South America, and Africa. Macrothrix boergeni Studer, 1878 from the Kerguelen Archipelago is redescribed and a neotype is selected. All populations in the southernmost portion of continental South America, Tierra del Fuego, Falklands, South Georgia, South Orkney Islands, and on the Antarctic Peninsula belong to M. oviformis Ekman, 1900. All the taxa described from this region—M. ciliata Vávra, 1900, M. odontocephala Daday, 1902, M. propinqua Sars, 1909, and, probably, M. inflata Daday, 1902—are junior synonyms of M. oviformis. Two new species are established: M. sarsi sp. nov. from the Cape region of South Africa and M. ruehei sp. nov. from Crozet, Marion islands, and Île Amsterdam. Macrothrix cf. flagellata Smirnov and Timms, 1983, previously known only from Tasmania, is found on Macquarie Island too. Differences between species from the southern hemisphere and Palaearctic M. hirsuticornis are summarized. It is demonstrated that characters of the general body shape (i.e. presence of a hood or a tooth on posterior head border) have a limited value for the systematics of Macrothrix. In contrast, some fine details, mostly missed by previous authors, are valuable for species discrimination. The present study increases the number of species recorded from the Antarctic‐Subantarctic region. Probably, the current pattern of Macrothrix distribution results from a disruption of a pan‐continental (early Mesozoic?) species complex. 相似文献
57.
58.
《Journal of Natural History》2012,46(21-22):1277-1300
ABSTRACTChrysoperla duellii sp. nov. is discovered, associated with coniferous vegetation, in the Kyrgyz Republic in central Asia, co-occurring with two other cryptic species of the Chrysoperla carnea-group. It is distinguished by its courtship duetting song, which exhibits a uniquely complex multi-volleyed temporal and tonal structure but is nevertheless noticeably convergent on the species-specific song of another conifer-associated member of the carnea-group, C. downesi (Smith), from North America. The song of C. duellii also shows some superficial similarity to those of European/north African C. mediterranea (Hölzel) and southern Californian C. calocedrii Henry et al., both of which, like C. duellii, prefer conifers and exhibit dark-green adult body pigmentation. The new species is herein formally described as Chrysoperla duellii Henry, Taylor and Johnson and is shown to be diagnosable by song and morphology from all other known members of the Chrysoperla carnea-group. Results of restriction site-associated DNA sequencing (RADseq) of C. duellii and five other carnea-group species strongly reject the hypothesis that similar songs and dark-green body colour among the four conifer-associated species are due to common ancestry, instead supporting independent, parallel acquisition of such features.http://www.zoobank.org/urn:lsid:zoobank.org:pub:4CA5BE5F-B4B9-4A7D-A801-C9AE1E895D0B 相似文献
59.
《Journal of Natural History》2012,46(7-8):387-402
The genus Ischnocolus is redefined based on type material, and extra specimens. Representatives of the genus are distinguished by clavate tarsal trichobothria arranged in median apical row; by the maxillae with lighter colour on prolateral edge. Males of the genus Ischnocolus Ausserer are recognized by the cheliceral intumescence, sigmoid ventral furrow on palpal tibia, unequal cymbium lobes, tibial apophysis absent, great number of spines on ventral side of tibia I, and male superior tarsal claws bipectinate. Species included are: Ischnocolus valentinus (Dufour) [= I. holosericeus L. Koch, I. triangulifer Ausserer, I. algericus Thorell, I. fuscostriatus Simon, I. maroccanus (Simon), I. mogadorensis (Simon), I. numidus Simon, I. tripolitanus Caporiacco, Avicularia andalusiaca Simon], Ischnocolus hancocki Smith, Ischnocolus jickelii L. Koch (senior-synonym of Chaetopelma adenense Simon) and Ischnocolus ignoratus sp. nov. Ischnocolus tomentosus Thorell is considered incertae sedis. The following species are considered species inquirenda: I. tunetanus Pavesi and I. fasciculatus Strand. http://www.zoobank.org/urn:lsid:zoobank.org:pub:207143F4-A235-4411-96D4-D4787ABF271F 相似文献
60.
《Journal of Natural History》2012,46(35-36):2277-2304
First records of Coelotinae are reported from Laos. Five new species of the genus Draconarius are described from the northern Luang Nam Tha Province: Draconarius bounnami sp. nov. (male), D. latidens sp. nov. (female), D. postremus sp. nov. (male, female), D. songi sp. nov. (male) and D. tabularis sp. nov. (female). In addition, two new Coelotinae species are described from Vietnam: D. hanoiensis sp. nov. (female) and D. huongsonensis sp. nov. (female). Of the 429 currently valid Coelotinae species, 154 of them have only females described (36%). The embolus characteristics of those with males described (275 species, 64%) are reviewed. Two characters have been found that might be informative for the estimation of phylogeny, and their congruence with the current Coelotinae classification system is discussed. One character is the point from which the embolus arises and another is the embolus shape. 相似文献