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21.
Abstract:  Three new genera and four new species of the extinct mantidfly subfamily Mesomantispinae (Insecta: Neuroptera: Mantispidae) are described from the Lower Cretaceous Yixian Formation of Liaoning and the Middle Jurassic Jiulongshan Formation of Inner Mongolia: Archaeodrepanicus nuddsi gen. et sp. nov., A. acutus gen. et sp. nov., Sinomesomantispa microdentata gen. et sp. nov., (Yixian Formation) and Clavifemora rotundata gen. et sp. nov. (Jiulongshan Formation). The specimens described herein represent the first Mesozoic mantidfly compression fossils to have body parts preserved, including the specialized raptorial forelegs articulated to the prothorax anteriorly, an autapomorphy of the family. These new taxa further confirm the placement of the subfamily Mesomantispinae within the family Mantispidae; however, the monophyly of Mesomantispinae has not been confirmed, and it is likely that it will prove to be paraphyletic.  相似文献   
22.
We use an integrative taxonomic approach to revise the genus Anisopteromalus. In particular, we apply multivariate ratio analysis (MRA), a rather new statistical method based on principal component analysis (PCA) and linear discriminant analysis (LDA), to numerous body measurements and combine the data with those from our molecular analysis of Cytb and ITS2 genetic markers (on a subset of species) and all available published data on morphology, karyology, behaviour, host associations and geographic distribution. We demonstrate that the analysis of quantitative characters using MRA plays a major role for the integration of name‐bearing types and thus for the association of taxa with names. Six species are recognized, of which two are new: A. cornis Baur sp.n. and A. quinarius Gokhman & Baur sp.n. For Anisopteromalus calandrae (Howard), a well‐known, cosmopolitan parasitoid of stored‐product pests, we have selected a neotype to foster continuity and stability in the application of this important name. The species was sometimes confused with the related A. quinarius sp.n. , another cosmopolitan species that is frequently encountered in similar environments. We also show that several species originally described or later put under Anisopteromalus actually belong to different genera: Cyrtoptyx camerunus (Risbec) comb.n. ; Meraporus glaber (Szelényi) comb.n. ; Dinarmus schwenkei (Roomi, Khan & Khan) comb.n. Neocatolaccus indicus Ayyar & Mani is confirmed as a junior synonym of Oxysychus sphenopterae (Ferrière) syn.n. and Anisopteromalus calandrae brasiliensis (Domenichini) stat.rev. must be considered as a valid but doubtful taxon. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:BDFE96D3‐D0F4‐4012‐90F5‐9A087F7F5864 .  相似文献   
23.
1. The paper by Sand‐Jensen (2003 , Freshwater Biology, 48 , 271–283) on drag and reconfiguration of freshwater macrophytes stimulated comments and a reply about the use of variables in assessments of the drag coefficient (Cd) or the Reynolds number (Re) of such plants. Although the physical argument in this debate starts from the same equations, it diverges into approaches that address differently the dynamic behaviour of flexible plants in the boundary layer flow (the typical condition experienced by lotic macrophytes). 2. We compared three (potentially among many more) such different approaches using some preliminary experiments with Egeria densa by measuring drag (and other physical variables of interest) on (1) a single shoot exposed to varying flume flows; (2) a single shoot exposed to a constant flume flow, from which we subsequently pruned off pieces from the distal end; and (3) multiple shoots exposed to a constant flume flow after they had experienced replicated flow disturbances (causing shoot reconfiguration). 3. These experiments illustrated that the three approaches can produce opposite trends in the relationship between Cd and Re and that, for a given plant and flow, the Cd values obtained by these approaches can differ by about two orders of magnitude. Thus, conventions about the use of variables are required for experiments on drag and reconfiguration of freshwater macrophytes, otherwise the field will be plagued by a multitude of incomparable results.  相似文献   
24.
Hieracium kittanae Vladimirov, a new diploid (2 n  = 18) species restricted to a few gorges in the Central Rhodope Mountains, south Bulgaria, is described and illustrated. It occurs in crevices of limestone rock in shady to sunny places with high atmospheric humidity. Morphologically, it to some extent resembles taxa from the H. glaucinum and H. schmidtii groups, but is otherwise very distinct, without close relatives in the Rhodope and neighbouring mountains.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003 , 143 , 213−218.  相似文献   
25.
Members of the megadiverse insect order Diptera (flies) have successfully colonized all continents and nearly all habitats. There are more than 154 000 described fly species, representing 10–12% of animal species. Elucidating the phylogenetic relationships of such a large component of global biodiversity is challenging, but significant advances have been made in the last few decades. Since Hennig first discussed the monophyly of major groupings, Diptera has attracted much study, but most researchers have used non‐numerical qualitative methods to assess morphological data. More recently, quantitative phylogenetic methods have been used on both morphological and molecular data. All previous quantitative morphological studies addressed narrower phylogenetic problems, often below the suborder or infraorder level. Here we present the first numerical analysis of phylogenetic relationships of the entire order using a comprehensive morphological character matrix. We scored 371 external and internal morphological characters from larvae, pupae and adults for 42 species, representing all infraorders selected from 42 families. Almost all characters were obtained from previous studies but required revision for this ordinal‐level study, with homology assessed beyond their original formulation and across all infraorders. We found significant support for many major clades (including the Diptera, Culicomorpha, Bibionomorpha, Brachycera, Eremoneura, Cyclorrhapha, Schizophora, Calyptratae and Oestroidea) and we summarize the character evidence for these groups. We found low levels of support for relationships between the infraorders of lower Diptera, lower Brachycera and major lineages of lower Cyclorrhapha, and this is consistent with findings from molecular studies. These poorly supported areas of the tree may be due to periods of rapid radiation that left few synapomorphies in surviving lineages.  相似文献   
26.
Ninety species of leaf beetles (Chrysomelidae, Coleoptera, Insecta) were recorded from die 'Evolution Canyon' microsite (sample area 7000 m2), Lower Nahal Oren, Mt Carmel, Israel. Species richness was significandy ( P =0.018) higher on the drier, climatically more fluctuating savanna-like, soudi-facing slope (SFS, 60 species, sample area 3000 m2) than on the cooler, wetter and climatically less variable north-facing slope (NFS, 44 species, sample area 3000 m2), as in other terrestrial taxa. More species were found common to the local xeric SFS at die Canyon and the regional southern desert areas (Judean and Negev Deserts), than to the NFS and Galilee Mountains, respectively, suggesting that local patterns mirror regional patterns. Interslope differences in microclimate variability range indicate that this factor might be determinant of interslope species richness differences. Most species were collected in the spring (April; 47%) and least in the autumn (September; 3%) over the collecting period from March 1995 to June 1997.  相似文献   
27.
28.
Abstract:  Remarkable new fossil taxa of Neuroptera from the laminated limestone of the Crato Formation, north-east Brazil, are described: Nuddsia longiantennata gen. et sp. nov. (Osmylidae, Gumillinae), the first fossil record of this family from South America, Parapalaeoleon magnus gen. et sp. nov. (Palaeoleontidae), and Triangulochrysopa formosa sp. nov. (Mesochrysopidae). A diagnosis of Gumillinae is provided; Epiosmylidae is considered to be a synonym of this subfamily. A revised diagnosis of Palaeoleontidae is provided, based on a new interpretation of venational characters evident on the exceptionally well-preserved specimen of P. magnus ; vein homologies are determined and the fusion of MP and CuA is discussed. The genus Triangulochrysopa has been known previously only from the Lower Cretaceous of Las Hoyas, Spain.  相似文献   
29.
SUMMARY. 1. The potential tor competition in the zooplankton of small Araucana Lake (Andes, Argentina) was tested experimentally.
2. Laboratory enrichment of lake water with nutrients resulted in an increased abundance of nannoplankton with the cyanobacteria Gloeocapsa minor predominating.
3. The dominant species of zooplankton showed contrasting responses to enrichment: the abundance of Bosmina longirostris increased, whereas that of Ceriodaphnia dubia decreased relative to the corresponding controls.
4. The clearance rates for various nannoplankton by these cladocerans were similar, resulting in high niche overlap as estimated by the Pianka index.
5. Life table experiments showed that when fed on a pure suspension of lake flagellates (103 cells ml−1) Ceriodaphnia had a significantly higher average intrinsic rate of natural increase ( r ) than on a suspension of Gloeocapsa (0.28 v . 0.146); in the case of Bosmina no significant differences for the two foods were found (0.182 and 0.141, respectively).
6. The contrasting responses of the animals to enrichment are explained by the differing suitability of particular nannoplankton species as food for different cladoceran species. The seasonal succession in the species composition and food quality of nannoplankton may be important for the coexistence of competing zooplankters in lakes.  相似文献   
30.
Nine microsatellite loci were isolated from the insect Dolichogenidea homoeosomae (Hymenoptera: Braconidae), an important parasitoid of the sunflower moth Homosoeosoma electellum (Lepidoptera: Pyralidae), and assayed for polymorphism. All nine loci were polymorphic within the five populations tested, with two to 14 alleles per locus. Expected and observed heterozygosities ranged from 0.39 to 0.90 and 0.25 to 0.72 respectively. These are the first microsatellite primers developed for D. homeosomae and will be useful for studies of population dynamics and connectivity.  相似文献   
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