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1.
All species that have been described of the genera mentioned in the title are listed and their systematic position given. The species of Stilifer (with 11 species, including S. inflatus sp.n. and 5. concavus sp.n.) are parasites of starfishes. Scalenostoma (3 species) are parasites of stone corals. Thyca (with 8 species) is removed from Capulidae, and included in Eulimidae. T. hawaiiensis sp.n. is described. The species of Thyca are parasites of starfishes. The species of Mucronalia (including M. trilineata sp.n.) are probably parasites of ophiuroids and Echineulima (with 4–6 species, including E. ponderi sp.n.) are parasites of echinoids. All species are figured, their characteristics are given and their host species and distributions are listed. Keys are given to the species of each genus, except Mucronalia. The genera Stilimella Laseron and Hyperlia Pilsbry are synonymized with Scalenostoma and the genera Kiramodulus Kuroda, Granulithyca Habe and Bessomia Berry are considered subgenera of Thyca.  相似文献   

2.
The data on the ciliates species composition are given for the Baltic Sea, a brackish-water semi-closed water body where a considerable part of the planktonic fauna is presented by freshwater species. During the observation period, 789 species of ciliates were found, 160 of which are typical planktonic forms. The ecological characteristics of ciliates are given, along with an assessment of their role in the productivity of the Baltic Sea pelagic communities.  相似文献   

3.
A list of the species now included in the genus is given with notes of their geographical distribution and (where possible) details of their ecology and a key for their identification. An amended diagnosis of the genus is given to include two new species, hitherto unnamed and known only from damaged and inadequate material, which are now named and fully described and figured.  相似文献   

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Li YJ  Li ZZ 《ZooKeys》2011,(120):1-8
The paper deals with the species of the Oriental leafhopper genus Taperus Li & Wang. A new species, Taperus daozhenensissp. n., from Guizhou Province, China is described and new records for other Chinese species are given together with a key for their separation. The type specimens of the new species are deposited in the Institute of Entomology, Guizhou University (GUGC).  相似文献   

5.
Aim In recent years evidence has accumulated that plant species are differentially sorted from regional assemblages into local assemblages along local‐scale environmental gradients on the basis of their function and abiotic filtering. The favourability hypothesis in biogeography proposes that in climatically difficult regions abiotic filtering should produce a regional assemblage that is less functionally diverse than that expected given the species richness and the global pool of traits. Thus it seems likely that differential filtering of plant traits along local‐scale gradients may scale up to explain the distribution, diversity and filtering of plant traits in regional‐scale assemblages across continents. The present work aims to address this prediction. Location North and South America. Methods We combine a dataset comprising over 5.5 million georeferenced plant occurrence records with several large plant functional trait databases in order to: (1) quantify how several critical traits associated with plant performance and ecology vary across environmental gradients; and (2) provide the first test of whether the woody plants found within 1° and 5° map grid cells are more or less functionally diverse than expected, given their species richness, across broad gradients. Results The results show that, for many of the traits studied, the overall distribution of functional traits in tropical regions often exceeds the expectations of random sampling given the species richness. Conversely, temperate regions often had narrower functional trait distributions than their smaller species pools would suggest. Main conclusion The results show that the overall distribution of function does increase towards the equator, but the functional diversity within regional‐scale tropical assemblages is higher than that expected given their species richness. These results are consistent with the hypothesis that abiotic filtering constrains the overall distribution of function in temperate assemblages, but tropical assemblages are not as tightly constrained.  相似文献   

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The karyotypes of three Lepilemuridae species, Lepilemur mustelinus, L. edwardsi, and L. dorsalis, are described and compared to those of three Lepilemur species previously reported. The phylogenetic relationships between the six species and their presumed last common ancestor are given. The results obtained, and the comparison with other groups, strongly suggest a monophyletic origin for all Malagasy lemurs.  相似文献   

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The loss of a species from an ecological community can trigger a cascade of secondary extinctions. The probability of secondary extinction to take place and the number of secondary extinctions are likely to depend on the characteristics of the species that is lost--the strength of its interactions with other species--as well as on the distribution of interaction strengths in the whole community. Analysing the effects of species loss in model communities we found that removal of the following species categories triggered, on average, the largest number of secondary extinctions: (a) rare species interacting strongly with many consumers, (b) abundant basal species interacting weakly with their consumers and (c) abundant intermediate species interacting strongly with many resources. We also found that the keystone status of a species with given characteristics was context dependent, that is, dependent on the structure of the community where it was embedded. Species vulnerable to secondary extinctions were mainly species interacting weakly with their resources and species interacting strongly with their consumers.  相似文献   

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Zhang Y  Wei C  Webb MD 《Zoological science》2007,24(4):414-426
The Oriental 'fly-like' leafhoppers of the Doda group are reviewed and a key is given for their separation. Two new genera and two new species are described: Pseudododa gen. n. (with type species P. orientalis sp. n.) and Aculescutellaris gen. n. (with type species A. hirtellus sp. n.). The variation within the former species is documented and illustrated, and the special mineral uptake behavior ('mud-puddling') of this genus and other Cicadellidae is reviewed.  相似文献   

13.
Developments in genetic engineering may soon allow biologists to clone organisms from extinct species. The process, dubbed “de-extinction,” has been publicized as a means to bring extinct species back to life. For theorists and philosophers of biology, the process also suggests a thought experiment for the ongoing “species problem”: given a species concept, would a clone be classified in the extinct species? Previous analyses have answered this question in the context of specific de-extinction technologies or particular species concepts. The thought experiment is given more comprehensive treatment here. Given the products of three de-extinction technologies, twenty-two species concepts are “tested” to see which are consistent with the idea that species may be resurrected. The ensuing discussion considers whether or not de-extinction is a conceptually coherent research program and, if so, whether or not its development may contribute to a resolution of the species problem. Ultimately, theorists must face a choice: they may revise their commitments to species concepts (if those concepts are inconsistent with de-extinction) or they may recognize de-extinction as a means to make progress in the species problem.  相似文献   

14.
ABSTRACT Six noctuid species: Ericeia pertendens (Walker), Nycteola costalis Sugi, Neustrotia albicincta (Hampson), Araeopteron flaccida Inoue, Feliniopisis indistans (Guenée), and Hadula stigmosa (Christoph), are newly recorded in the Korean fauna. The photographs of the adults and their genitalia are given for each species, together with notes on their bionomy and distribution.  相似文献   

15.
1. Regional distribution, frequency of occurrence and relative abundance were scored in 2467 Norwegian lakes for all the recorded 130 species of crustacean zooplankton. The majority of species were rare in the sense that 65% of species were recorded in fewer than 10% of localities. Only six species were recorded in more than 50% of localities, and the median number of species in a given locality was 14 (i.e. 10% of the total species pool). 2. Abundances of all species were scored according to the fraction of lakes in which they were recorded, their geographical range of distribution, and their numerical abundance. Typically the most rare species were rare by all three criteria, and vice versa for the common species, pointing to rarity as an inherent property of some species. For some species this rarity reflects being on the edge of their distributional range, while for others rarity seems to be a consequence of their life cycle strategies. 3. Some of the truly rare species have high dispersal rates and high colonization abilities, but are rapidly replaced by other species. Others are confined to specific habitats, often highly eutrophic, pointing to highly specialized niche adaptations. 4. A major cause for the few truly common species seems to be the limited number of species that are able to coexist within a given locality, reflecting ‘the ghost of competition past’ and predation pressure. 5. While species composition and species richness may reflect colonization abilities and stochastic events, the presence or absence of species is not only a random lottery but also a consequence of species‐specific attributes.  相似文献   

16.
An account is given of a severe attack to grassland by chafer-beetle larvae in some north Wales valleys in the years 1942-3. The species concerned were Phyllopertha horticola L. and Hoplia philanthus Fuess. Estimations of the populations of both species were made and notes are given on the biology and comparative morphology of their immature stages. Both species have a one-year life cycle; all stages of Hoplia philanthus occur somewhat later than Phyllopertha horticola.  相似文献   

17.
中国东北地区木材腐朽菌的多样性(英文)   总被引:4,自引:7,他引:4  
戴玉成 《菌物学报》2010,29(6):801-818
对中国东北地区木材腐朽菌资源研究进行了总结,给出了每种木材腐朽菌的寄主和在东北的分布。目前中国东北地区共记载木材腐朽菌504种,其中300种为多孔菌,204种为革菌,57种为林木病原菌,69种为药用菌。梨多年卧孔菌Perenniporia pyricola和北方赖特孔菌Wrightoporia borealis为新种,对它们进行了描述和绘图。对所有名称按最新命名法规(维也纳法规)进行了订正。  相似文献   

18.
One hundred and sixty eight species of parasite are listed from 36 species of freshwater fish from Britain and Ireland, and notes on their distribution are provided. A list of hosts together with the parasites recorded from them is also given. Although almost twice as many species are listed as in the most recent published reference list, the parasite fauna of Britain appears to be considerably poorer in number of species than that of mainland Europe, and that of Ireland poorer still. The distribution of most species, apart from two endemic species and a very few which have clearly been introduced into Britain in recent years from America or the mainland of Europe, appears to show no peculiarities and is probably contiguous with that of their hosts.  相似文献   

19.
Summary Several measures of interspecific association are compared. Dispersion and covariance are limited in value because they respond to the commonness of the species compared. Correlation is not so limited but it responds to discrepancies in commonness among the species. The practical result of these relationships between commonness and association is that only the most common species can occupy periferal positions in a species ordination. Rare species are relegated to positions near the center not on the basis of their phytosociological pattern but simply because of their rarity. Both Cole's index of association and the tetrachoric correlation overcome the problem imposed by the relationship between ordination position and species commonness and they both produce very similar results. The effect of differing numbers of species on the ordination configuration is examined using both Pearson's correlation and Cole's index. The basic pattern of the ordination is set with the first few species when Cole's index is used, however, since rare species are given more weight in the analysis with this index, the addition of several very rare species can change the configuration of the ordination.Nomenclature of species is given in Table 1.Research supported by the Eastern Deciduous Forest Biome Project, US-IBP, funded by the National Science Foundation under Interagency Agreement AG-199, BMS69-01147 A09 with the Energy Research and Development Administration — Oak Ridge National Laboratory. Research also supported by the U.S. Energy Research and Development Administration under contract with the Union Carbide Corporation. Contribution No. 240 from the EDFB, US-IBP. Publication No. 790. Environmental Sciences Division, ORNL.  相似文献   

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