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141.
Five new genera of the spider family Ochyroceratidae with remarkable palpal and epigynal characters are described:Luzonacera Li & Li,gen.nov.,Qiongocera Li & Li,gen.nov.,Relictocera Li & Li,gen.nov.,Sinoderces Li & Li,gen.nov.,and Thaiderces Li & Li,gen.nov.Six new species are described based on specimens collected in China,Philippines,Vietnam,and Thailand:Luzonacera chang Li & Li,sp.nov.,Luzonacera duan Li & Li,sp.nov.,Qiongocera hongjunensis Li & Li,sp.nov.,Relictocera qiyi Li & Li,sp.nov.,Sinoderces nawanensis Li & Li,sp.nov.,and Thaidercesjian Li & Li,sp.nov.In addition,two Psiloderces species are transferred to other genera:Sinoderces exilis (Wang & Li,2013) comb.nov.and Thaiderces vulgaris (Deeleman-Reinhold,1995) comb.nov.All type specimens are deposited in the Institute of Zoology,Chinese Academy of Sciences (IZCAS) in Beijing. 相似文献
142.
青蟹线粒体COI假基因的分离和特征分析 总被引:6,自引:0,他引:6
线粒体DNA标记在遗传结构和系统进化研究中得到广泛应用,然而核假基因的存在对此有很大威胁。本文以中国东南沿海的青蟹(Scylla paramamosain)为研究对象,利用线粒体COI基因的通用引物和特异性引物进行扩增,分别得到34个假基因(nuclear mitochondrial pseudogenes, Numts)和5个线粒体COI基因序列。在所获得的34个假基因中共定义了29种单倍型,根据序列的相似度,这些假基因可以分为2类,每类假基因都有各自保守的核苷酸序列。第Ⅰ类假基因存在2处插入序列和1处8 bp的缺失序列,这些位点导致了整个阅读框的移位;在第Ⅱ类假基因和5个线粒体COI序列中只有碱基替换,未发现插入和缺失序列。实验结果分析表明,这两类假基因分别代表了2次核整合事件,即核转移事件的最低值。研究结果提示了 相似文献
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J. L. Horreo 《Journal of evolutionary biology》2012,25(12):2661-2664
Despite the problems associated with the one‐gene‐constructed phylogenetic relationships, recently it has been shown that merely adding more sequences to the analyses is not enough to resolve all the inconsistencies present in these relationships. In this work, the existence of ‘representative’ genes for groups of species is evaluated in terms of efficiency (costs/benefits), employing the cytochrome c oxidase subunit I (COI) and the penguins' phylogeny as a case study. ‘Representative’ genes are very useful and they could produce good results for first approaches or humble laboratories, especially if the gene is chosen depending on the time scale and objectives of our work. 相似文献
145.
Juan L. Hernández‐Roldán Cesc Múrria Helena Romo Gerard Talavera Evgeny Zakharov Paul D. N. Hebert Roger Vila 《Journal of Biogeography》2011,38(10):2006-2020
Aim To study the biogeographical factors responsible for the current disjunct distributions of two closely related species of butterflies (Pyrgus cinarae and Pyrgus sidae, Lepidoptera: Hesperioidea). Both species have small populations in the Iberian Peninsula that are isolated by more than 1000 km from their nearest conspecifics. Because these species possess similar ecological preferences and geographical distributions, they are excellent candidates for congruent biogeographical histories. Location The Palaearctic region, with a special focus on the Mediterranean peninsulas as glacial refugia. Methods We integrated phylogeography and population genetic analyses with ecological niche modelling. The mitochondrial gene cytochrome c oxidase subunit 1 (COI) and the non‐coding nuclear marker internal transcribed spacer 2 (ITS2) were analysed for 62 specimens of P. cinarae and for 80 of P. sidae to infer phylogeography and to date the origin of disjunct distributions. Current and ancestral [Last Glacial Maximum using MIROC (Model for Interdisciplinary Research on Climate) and CCSM (Community Climate System Model) circulation models] distribution models were calculated with Maxent . Using present climatic conditions, we delimited the ecological space for each species. Results The genetic structure and potential ancestral distribution of the two species were markedly different. While the Iberian population of P. cinarae had an old origin (c. 1 Ma), that of P. sidae was closely related to French and Italian lineages (which jointly diverged from eastern populations c. 0.27 Ma). Ecological niche modelling showed that minor differences in the ecological preferences of the two species seem to account for their drastically different distributional response to the last glacial to post‐glacial environmental conditions. Although the potential distribution of P. cinarae was largely unaffected by climate change, suitable habitat for P. sidae strongly shifted in both elevation and latitude. This result might explain the early origin of the disjunct distribution of P. cinarae, in contrast to the more recent disjunction of P. sidae. Main conclusions We show that convergent biogeographical patterns can be analysed with a combination of genetic and ecological niche modelling data. The results demonstrate that species with similar distributional patterns and ecology may still have different biogeographical histories, highlighting the importance of including the temporal dimension when studying biogeographical patterns. 相似文献
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148.
Assessing ecological and molecular divergence between the closely related species Hydrolagus pallidus and H. affinis (Chimaeridae)
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B. Violi M. R. Gaither F. Burns A. Rus Hoelzel F. Neat 《Journal of fish biology》2018,92(4):1211-1217
This study investigated taxonomic validity of the pale ghost shark Hydrolagus pallidus Hardy & Stehmann, 1990, which was described as a species distinct from the smalleyed rabbitfish H. affinis (de Brito Capello 1868). While few morphological characters distinguish the two taxa, a striking difference in sex ratio and fixed differences (1·1–1·6% divergence) in the cytochrome oxidase subunit I barcoding gene support the recognition of both species. 相似文献
149.
Surprising diversity in the Pannonian populations of Marsh Fritillary (Euphydryas aurinia,Lepidoptera: Nymphalidae): Morphometric and molecular aspects
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Katalin Pecsenye Andrea Tóth János P. Tóth Judit Bereczki Gergely Katona Zoltán Varga 《Journal of Zoological Systematics and Evolutionary Research》2018,56(4):519-532
Since genetic variation is the basis of evolutionary potential of a species, its structure needs to be understood. Thus, the aim of this study was to analyze and contrast the structure of genetic and phenotypic variation in the Euphydryas aurinia populations of southeastern central Europe. Genetic variation was studied by two types of molecular genetic markers: mtDNA COI sequences and allozymes. As the great hiatus in the European distribution of E. aurinia is located in the central part of the Carpathian Basin, we expected that the populations East and West to this gap would be highly differentiated. Populations of Central Transdanubia actually represent the easternmost margin of the West European distribution of E. aurinia. In view of the peripheral position of these populations, we supposed to find some genetic sign of local adaptation, as a consequence of diversifying selection and an increased level of fluctuating asymmetry as a result of environmental stress. The analyses of the molecular genetic markers revealed a basic East–West differentiation among the populations of southeastern central Europe which was further structured in the western part of the study area. The results suggested that the genetic differentiation between the two western regions is probably the consequence of diversifying selection. The pattern of phenotypic differentiation among the western populations, however, was different. A geographic cline was revealed (decreasing wing size) toward the eastern margin of the distribution in parallel with increasing fluctuating asymmetry. The conservation inferences of the results are considered. 相似文献
150.
Zorica Nedeljković Ante Vujić Rüstem Hayat Ljiljana Šašić Zorić Mihajla Đan 《Zoology in the Middle East.》2018,64(3):244-252
A new species of the genus Chrysotoxum (Diptera: Syrphidae), Chrysotoxum bozdagensis Nedeljkovi?, Vuji? &; Hayat sp. n., collected from Bozda? Mt., ?zmir Province, Turkey is described and illustrated. Chrysotoxum bozdagensis sp. n. can be distinguished from the similar Ch. octomaculatum Curtis, 1837 by the presence of a black pile on the mesonotum and the colour of the legs. It is also similar to Ch. elegans Loew, 1841, from which it can be distinguished by the colour of the pile on the vertical triangle and scutellum, as well from the structure of the male genitalia. Additionally, Ch. bozdagensis sp. n. can be clearly distinguished from the latter two species by DNA sequence data. This new species increases the total number of Chrysotoxum species in Turkey to 18.http://www.zoobank.org/urn:lsid:zoobank.org:pub:7465AAEA-21E6-4F0F-984C-CD48BE75436F 相似文献