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941.
MICHAEL STAAB ANDREAS SCHULDT THORSTEN ASSMANN ALEXANDRA‐MARIA KLEIN 《Ecological Entomology》2014,39(5):637-647
1. Epigeic ants are functionally important arthropods in tropical and subtropical forests, particularly by acting as predators. High predation pressure has been hypothesised to be a mechanism facilitating high diversity across trophic levels. 2. In this study, standardised pitfall traps were used in a highly diverse subtropical forest to test if and how ant species richness is related to tree species richness and a comprehensive set of other environmental variables such as successional age, soil properties or elevation. 3. A total of 13 441 ant individuals belonging to 3839 species occurrences and 71 species were collected, of which 26 species were exclusive predators and 45 species were omnivores. 4. Occurrence and species richness of total and omnivore ants were positively related to soil pH. Predator ant occurrence was unrelated to all environmental variables tested. 5. The species richness of predator ants increased with tree species richness but decreased with leaf functional diversity and shrub cover. Elevation negatively influenced only total ant species richness. 6. The evenness of predators increased with tree species richness, while the evenness of all ants decreased with shrub cover. Omnivore ant evenness decreased with tree evenness, but increased with successional age. 7. The results highlight the value of diverse forests in maintaining species richness and community evenness of a functionally important predator group. Moreover, the results stress the importance of analysing trophic groups separately when investigating biodiversity effects. 相似文献
942.
943.
Abstract The tribe Trypetimorphini, the genus Ommatissus , and its two subgenera and eleven species are redescribed or described as new. Evidence for the monophyly of both the genus and of the tribe to which it belongs is examined; it is concluded that while the genus is monophyletic, the monophyly of the tribe is in doubt. Keys for the separation of the three genera of the tribe and for all of the known species of Ommatissus are presented. A new subgenus of Ommatissus is described: O.(Opatissus) , with the type-species O.vietnamicus . Four new species are described: Ommatissus magribus from Morocco, O.kamerunus from Cameroon, O.natalensis from South Africa and O.vietnamicus from Vietnam. The 'Dubas bug', Ommatissus lybicus Bergevin, formerly regarded as a variety of O.binotatus Fieber, is raised to full species status. Trichoduchus is synonymized with Trypetimorpha resulting in the new combinations Trypetimorpha biermani Dammerman, T.china Wu and T.japonicus Ishihara. Trichoduchus japonicus Fennah is synonymized with Trypetimorpha japonicus Ishihara. 相似文献
944.
ALAN W. MEEROW MICHAEL GIDEON DAVID N. KUHN RAYMOND J. SCHNELL 《Molecular ecology resources》2005,5(2):410-412
Ten microsatellite loci isolated from Iris hexagona are described. All these loci are polymorphic, with three to 13 alleles across 24 individuals from a single natural population. Heterozygosity ranged from 0.125 to 0.870. Three loci depart significantly from Hardy–Weinberg equilibrium in our test population. The test population shows significant heterozygote deficiency in these and two other loci. Three loci exhibit significant linkage disequilibrium. These loci will be utilized to investigate patterns of genetic variation in the species throughout the Florida peninsula. 相似文献
945.
946.
947.
948.
R. MICHAEL C. EAGAR 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1974,7(3):219-238
In the British Pennines, from the middle of the lenisulcata Zone to the lower part of the communis Zone (Upper Carboniferous, lower Westphalian A), nine horizons, of which six are new or newly described, yield elongate specimens of the bivalve Carbonicola with evidence of former steep, near vertical burrowing in sediments of low organic carbon content. The faunas, of the groups of C. bellula (Bolton) sensu lato and of elongate C. aff. communis Davies & Trueman, were evidently invaders of the Pennine prodelta. They grade with established faunas of prolific highly variable Carbonicola found typically in richly carbonaceous shales and characterised by shallow burrowing, greater size, increased prcportionate shell height and length of anterior end, and probably increased obesity. Parallels exist with work on Anthraconaia. Anthraconauta . and the ecology of recent Unionacea. Results also bear on the palaeoecological ranges of Curvirimula and Naiadites . 相似文献
949.
950.
Seeds irradiated with red light and then re-dried will respondto this light treatment on subsequent rehydration in the dark.If such high-Pfr seeds are irradiated in the dry state withfar-red light immediately before rehydration the percentagegermination is significantly reduced in the case of Plantagomajor and Sinapis arvensis but increased in Bromus steriliswhere Pfr inhibits germination. This effect of far-red lightcan be reversed by red light despite the fact that red lightalone has no effect on dry seed. This is due to the interconversionof Pfr and the red light absorbing phytochrome intermediatecomplex meta-Fa. If there is a delay between far-red irradiationand rehydration of Sinapis seeds, the inhibitory effect of thefar-red irradiation becomes progressively less the longer thedelay. This reduction in effectiveness of far-red is interpretedin terms of a dark reversal of meta-Fa to Pfr with a half-lifeof about 46 h. The reappearance of Pfr is either veryslow or docs not occur in dehydrated Plantago seeds, as far-redtight given 96 h prior to hydration is just as inhibitory asfar-red light given immediately before hydration. Meta-Fa doesappear to revert to Pfr in darkness in Bromus seeds, but onlyvery slowly. The rapid increase in effectiveness of red irradiationduring rehydration of high-Pfr Plantago seeds suggests that,in this species, the pre-treatment used in preparation of high-Pfrseeds may increase the receptivity or amount of the Pfr reactionpartner. Key words: Phytochrome intermediates, Seeds, Germination 相似文献