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1.
The genus Hemibidessus Zimmermann, 1921 is revised. Six species are recognized in the genus. Two new species are described, H. spirodiscus sp. n. from Bolivia and H. spangleri sp. n. from Argentina. A key for identifying the species is presented. The female genitalia are thoroughly illustrated and described for the first time for any species of Bidessini. Other important diagnostic structures are also illustrated including the male genitalia. A cladistic analysis is presented for 8 species (6 ingroup and 2 outgroup species) and 13 characters. A single most parsimonious cladogram was found.  相似文献   

2.
A new species of Spauligodon , Spauligodon latasticola n. sp., from the intestines of Latastia longicaudata (Lacertidae) from Kenya is described and illustrated. Spauligodon latasticola represents the 47th species assigned to the genus and the 8th species from the Ethiopian region. The new species differs from all but 2 other species assigned to Spauligodon by the presence of a conically tapering tail in the female. The new species is separated from the 2 similar species, Spauligodon garciaprietoi and Spauligodon goldbergi, by the position of the vulva, which is anterior to the esophageal bulb in the new species, at the level of the esophageal bulb in S. goldbergi, and posterior to the esophageal bulb in S. garciaprietoi.  相似文献   

3.
阔颈叶蝉属现全世界已知2种,中国均有分布。本文记述1新种,新种模式标本保存在西北农林科技大学昆虫博物馆。  相似文献   

4.
The jumping plant-lice or psyllids belonging to the subfamily Liviinae are reviewed. Nineteen species are recognized in a single genus Lima Latreille. Three new species, craivfordi sp. nov., lobata sp. nov. and manitobensis sp. nov., are described. The identities of the existing species have been widely confused and full lists of synonymies are given where appropriate. It is re-emphasized that the type species of Livia, Psylla juncorum Latreille, is a synonym of Chermes junci Schrank, a point made by Laing (1951) but ignored by subsequent authors. The latter name has priority. A taxonomic key for the identification of the species is given and each species is described, diagnosed and illustrated. Supporting information is given on geographical distribution, host-plant association and general biology. Evolutionary relationships within Livia are discussed.  相似文献   

5.
The taxonomy of the New World species of the genus Trichadenotecnum is revised. A total of 44 species, including 29 new species, were treated. These species are classified into 12 monophyletic species groups, eight of them newly proposed here. Two species previously assigned to Trichadenotecnum , T. pichincha New & Thornton and T. sylvaticum Turner, are recognized as not belonging to this genus. Phylogenetic relationships among 16 previously and presently proposed species groups are estimated based on a data matrix of 58 morphological characters. Trees from these analyses support monophyly of Trichadenotecnum and the proposed species groups. The New World species were divided into three major clades. Based on the phylogenetic hypothesis and distributional pattern of the species groups, the biogeographical history of the New World Trichadenotecnum is discussed.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 153 , 651–723.  相似文献   

6.
The anomuran crabs are among the best known crustacean groups from the Pacific coast. However, this group is poorly known from the Caribbean coast of Costa Rica. In this compilation based on the literature and the collection at the Zoology Museum, Biology School, University of Costa Rica, we report the presence of 114 species of the Infraorder Anomura for Costa Rica, 20 species from the Caribbean, 96 species from the Pacific (two are present on both coasts). Twenty-nine species are new reports for Costa Rica, 15 from the Caribbean coast (74% of the total of species from that coast) and 14 from the Pacific (15% of the total from the Pacific). The range often species is extended to Costa Rica, siete from the Caribbean and three from the Pacific. Six species are reported for the first time from Cocos Island, where there are also four endemic species.  相似文献   

7.
The false spider crabs of the family Hymenosomatidae are one of the most poorly known group of brachyuran crabs in Southeast Asia. This is largely attributed to their small size and cryptic behaviour. Despite the many studies of decapods in Southeast Asia, only eleven species of hymenosomatids are known. Of these, two genera and six species were only described in the last two years. From Singapore the largest number of species (five) has been reported probably because it has been the best explored, while from Thailand three species and Peninsular Malaysia two species are known. There are no published records of hymenosomatids from Borneo or Java. The hymenosomatid fauna is perhaps best known in Australia and New Zealand. It is anticipated that when proper collections are made and studies implemented, the Southeast Asian hymenosomatid fauna will prove to be more diverse than what has been reported. The ecology of the Southeast Asian species is reviewed, especially in the view that two species are completely freshwater, one of which is a troglobite. Most species are littoral or sublittoral in habit and very sensitive to human activities (e.g. pollution).  相似文献   

8.
Abstract. Pamexis Hagen, 1866, is revised. Myrmeleon luteum Thunberg is designated as type species. A key is provided for the five species comprising the genus. Pamexis luteus (Thunberg, 1784), P.bifasciatus (Olivier, 1811) and P.contaminatus (Hagen, 1887) are redescribed: P.karoo and P.namaqua are new species. All are endemic to the Cape Province of South Africa.  相似文献   

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11.
Species: the concept, category and taxon   总被引:2,自引:0,他引:2  
The term species by itself is vague because it refers to the species concept, the species category and the species taxon, all of which are distinct although related to one another. The species concept is not primarily a part of systematics, but has always been an integral part of basic biological theory, It is based on evolutionary theory and applies only to sexually reproducing organisms. The species concept and the phyletic lineage concept are quite distinct although they are related to one another. The important aspect of the species concept is lack of gene flow between different species, and hence the defining criterion of the species is genetic isolation. The species concept is often considered as non‐dimensional, both in time and space. Species possess three different major properties, namely genetic isolation, reproductive isolation and ecological isolation; these properties evolve at different times and under the effect of different causes during the speciation process. Speciation requires an external isolating barrier during the initial allopatric phase in which genetic isolation evolves and must reach 100% efficiency. The subsequent sympatric phase of speciation occurs after the disappearance of the external isolating barrier when members of the two newly evolved species can interact with one another and exert mutual selective demands on one another. Much of the reproductive and ecological isolation evolves during this secondary sympatric phase. The species category is a rank in the taxonomic hierarchy and serves as the basis on which the diversity of organisms is described; it is not the same as the species concept. The species category applied to all organisms, sexually and asexually reproducing. The species taxon is the practical application of the species category in systematics with the recognition of species taxa requiring many arbitrary decisions. No single set of rules exist by which the species category can be applied to all organisms. Recognition of species taxa in asexually reproducing organisms is based on amount of variation and gaps in the variation of phenotypic features associated with ecological attributes of these organisms as compared with similar attributes in sympatric species taxa of sexually reproducing organisms. Species taxa are multidimensional in that they exist over space–time and often have fuzzy borders. Because recognition of species taxa, including those in sexually reproducing organisms, depends on many arbitrary decisions especially when dealing with broad geographical and temporal ranges, species taxa cannot be used as the foundation for developing and testing theoretical concepts in evolutionary theory which can only be done with the non‐dimensional species concept.  相似文献   

12.
Based on original and on published databases, a compendium of the Harpacticoida of the South China Sea is presented, and the distributional range of species is discussed. Up to now, a total of 77 harpacticoid species belonging to 57 genera and 19 families have been recorded in this region. Twenty of these species, collected in Nha-Trang Bay (Vietnam), have not hitherto been described. The most speciose families are the Miraciidae (20 species) and the Laophontidae (9 species). Thirteen families were represented by one to three species only and six families by four to seven species. A brief comparison is presented between the harpacticoid fauna of the South China Sea, the Philippine Islands, the inner Malayan Archipelago (Java, Flores, Banda, and Celebes Seas), New Guinea, the Yellow Sea, and the Andaman and Nicobar Islands. The overall similarity between the species lists of these areas was observed to be extremely low (average value of Simpson index is 0.15 ± 0.08). The lists of planktonic species from the different areas showed the highest similarity. The lowest similarity (highest endemism) was observed between the lists of interstitial species. It is likely that one of the factors determining the differences between the faunas is the poor knowledge about the composition and distribution of benthic harpacticoids in tropical latitudes.  相似文献   

13.
Abstract. The genus Microdonacia Blackburn is revised and its systematic position considered. Ten species are treated, seven of which are new ( bidentata, eucryphiae, grevitteae, incurva, octodentata, pilosa, pomaderris ), and lectotypes are designated for two species. Four of the new species are placed in Tantawangalo subgen.n. Microdonacia is compared with the genera Cassena Weise, Licyllus Jacoby and Orthaltica Crotch. The sister-group for Microdonacia is identified as Orthaltica and these genera are placed incertae sedis in the Galerucinae, as used in the sense of Crowson (1967). The proposed phylogeny of the species is illustrated on a cladogram.  相似文献   

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15.
Some species of parasites occur on a wide range of hosts while others are restricted to one or a few host species. The host specificity of a parasite species is determined, in part, by its ability to disperse between host species. Dispersal limitations can be studied by exploring the genetic structure of parasite populations both within a single species of host and across multiple host species. In this study we examined the genetic structure in the mitochondrial cytochrome oxidase I (COI) gene of two genera of lice (Insecta: Phthiraptera) occurring on multiple sympatric species of doves in southern North and Central America. One genus, Columbicola, is generally less host-specific than the other, Physconelloides. For both genera we identified substantial genetic differentiation between populations of conspecific lice on different host species, generally 10-20% sequence divergence. This level of divergence is in the range of that often observed between species of these two genera. We used nested clade analysis to explore fine scale genetic structure within species of these feather lice. We found that species of Physconelloides exhibited more genetic structure, both among hosts and among geographical localities, than did species of Columbicola. In many cases, single haplotypes within species of Columbicola are distributed on multiple host species. Thus, the population genetic structure of species of Physconelloides reveals evidence of geographical differentiation on top of high host species specificity. Underlying differences in dispersal biology probably explain the differences in population genetic structure that we observed between Columbicola and Physconelloides.  相似文献   

16.
We present the first global assessment of extinction risk for a major group of freshwater invertebrates, caridean shrimps. The risk of extinction for all 763 species was assessed using the IUCN Red List criteria that include geographic ranges, habitats, ecology and past and present threats. The Indo-Malayan region holds over half of global species diversity, with a peak in Indo-China and southern China. Shrimps primarily inhabit flowing water; however, a significant subterranean component is present, which is more threatened than the surface fauna. Two species are extinct with a further 10 possibly extinct, and almost one third of species are either threatened or Near Threatened (NT). Threats to freshwater shrimps include agricultural and urban pollution impact over two-thirds of threatened and NT species. Invasive species and climate change have the greatest overall impact of all threats (based on combined timing, scope and severity of threats).  相似文献   

17.
波翅青尺蛾属Thalera世界共记录6种和5亚种。中国已知3种和3亚种,本文记述5种和3亚种,其中包括采自四川巴塘1新种淡波翅青尺蛾Thalera simpliria sp.nov.和1新纪录种。文中给出了中国波翅青尺蛾属分种检索表和新种的成虫及外生殖器图。淡波翅青尺蛾,新种Thalera simpliria sp.nov.(图2,3,6,7)新种与Th.lacerataria Graeser,1889相似,但有以下不同:新种前翅外缘在M1与M3之间的缺刻极浅;前后翅外线较圆滑:♂外生殖器抱器瓣基部的三角形骨化片细尖,囊形突较细,钩形突较短粗;♀外生殖器后阴片有一方形弱骨化区域。  相似文献   

18.
A modified version of Schoener's non-linear competition model is presented. The model describes the competitive dynamics of two species competing for a common resource. A second resource made available by species 1 for the exclusive use of species 2 is also present. This second resource is generated in an undefined way from the common resource. The presence of the exclusive resource serves to prevent the extinction of species 2 even when that species is at a great competitive disadvantage in obtaining the common resource. A feedback loop is established, dependent on the exclusive resource, making possible an increase in numbers of species 2 as the numbers of species 1 increase. This is represented as a reversal in the slope of the species 2 isocline. The behavior of the isoclines of both species is examined as certain key parameters are varied. The model is related to the results obtained from experiments involving Tribolium and Drosophila.  相似文献   

19.
对近来记述的古北区东部地区的毛地蜂属Panurginus Nylander全部14个种作了补充研究。中国对该属的研究较少,仅知2种:黑足毛地蜂Panurginus nigripes Morawitz 和黄跗毛地蜂Panurginus flavotarsus ? Wu。黑毛地蜂Panurginus niger Nylander为该属的模式种,分布于俄罗斯和蒙古,本文报道该种为中国新记录种。目前,中国已知该属3种,分属于2个组即niger-group和herzi-group。文中提供了中国已知种类检索表。  相似文献   

20.
The genus Laupala is endemic to the rain forested islands of the Hawaiian archipelago. In his 1994 study Otte described 35 Laupala species, each restricted to a single island, and sometimes a single volcano. All Laupala species produce male calling songs consisting of slow trills. Two new species described here, one from the Koolau Mountains of Oahu and another from Kipahulu Valley of East Maui, produce the fastest and one of the slowest pulse rates, respectively, in the genus. Both species are found with sympatric congeners. The discovery of these species increases the acoustic diversity locally (within their respective communities), within their respective islands, and across the archipelago. This enhances the opportunity for the investigation of signal interference and character displacement in a relatively youthful assemblage of closely related species of crickets.  相似文献   

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