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A world revision of Strobilomyia gen.n.: the anthomyiid seed pests of conifers (Diptera: Anthomyiidae) 总被引:1,自引:0,他引:1
VERNER MICHELSEN 《Systematic Entomology》1988,13(3):271-314
Abstract. The world species of anthomyiid cone and seed pests are revised. A new genus, Strobilomyia gen.n., is erected for the eighteen species, including seven new to science, presently recognized. Author's views on homologies in the male and female terminalia of Anthomyiidae and other Diptera Cyclorrhapha are amplified as background for the terminology employed. The monophyly and systematic position of Strobilomyia are discussed with reassessions of related genera: Lasiomma Stein, Chirosia Rondani, Egle Robineau-Desvoidy and Acklandia Hennig. Zoogeographic aspects, especially vicariance across the Beringia, are analysed from a partial hypothesis of phylogenetic relationships among the species of Strobilomyia in conjunction with paleo-environmental data. New generic synonyms are: Macrophorbia Malloch, Crinurina Karl, Si-nohylemya Hsue (all =Lasiomma); Acrostilpna Ringdahl, Shakshainia Suwa, Meliniella Suwa (all =Chirosia). The species recognized in Strobilomyia (with geographic range and host trees in parentheses) are: anthracina (Czerny) (Palearctic, Picea); neanthracina sp.n. (Nearctic, Picea and ITsuga); appalachensis sp.n. (E. Nearctic); melania (Ackland) (Europe, Larix); sibirica sp.n. (N.E. Europe, Siberia, Larix); viaria (Huckett) (E. Palearctic, Nearctic, Larix); infrequens (Ackland) (Palearctic, Larix); luteoforceps (Fan & Fang) (E. Palearctic, Larix); baicalensis (Elberg) (E. Palearctic, Larix); laricicola (Karl) (Palearctic, Larix); laricis sp.n. (Nearctic, Larix); macalpinei sp.n. (W. Canada, Larix); carbonaria (Ringdahl) (C. Europe, E. Nearctic, Abies); svenssoni sp.n. (N. Europe, Mongolia); suwai sp.n. (Japan); todocola (Suwa) (Japan, Abies); abietis (Huckett) (Nearctic, Abies); and oriens (Suwa) (E. Palearctic, Abies). 相似文献
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Moult of some palaearctic migrant passerines was studied at a wintering site in northern Ghana, West Africa. We present data on moult pattern and estimated moult duration for a sample of species. Savi's Warbler Locustella luscinioides , Woodchat Shrike Lanius senator and probably Grasshopper Warbler Locustella naevia deviated from the ordinary descendent moult sequence. Different measures of moult speed (moult speed of retrapped individuals, growth of individual feathers, wing raggedness and first date of completion of moult) showed unexpectedly rapid moult among individuals of several species, notably the Great Reed Warbler Acrocephalus arundinaceus and the Sedge Warbler A. schoenobaenus. The rapid moult might be an adaptation to a limited period of abundant food which comes to an end at the beginning of the dry season. 相似文献
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Fifteen years of climate change manipulations alter soil microbial communities in a subarctic heath ecosystem 总被引:2,自引:0,他引:2
Soil microbial biomass in arctic heaths has been shown to be largely unaffected by treatments simulating climate change with temperature, nutrient and light manipulations. Here, we demonstrate that more than 10 years is needed for development of significant responses, and that changes in microbial biomass are accompanied with strong alterations in microbial community composition. In contrast to slight or nonsignificant responses after 5, 6 and 10 treatment years, 15 years of inorganic NPK fertilizer addition to a subarctic heath had strong effects on the microbial community and, as observed for the first time, warming and shading also led to significant responses, often in opposite direction to the fertilization responses. The effects were clearer in the top 5 cm soil than at the 5–10 cm depth. Fertilization increased microbial biomass C and more than doubled microbial biomass P compared to the non-fertilized plots. However, it only increased microbial biomass N at the 5–10 cm depth. Fertilization increased fungal biomass and the relative abundance of phospholipid fatty acid (PLFA) markers of gram-positive bacteria. Warming and shading decreased the relative abundance of fungal PLFAs, and shading also altered the composition of the bacterial community. The long time lag in responses may be associated with indirect effects of the gradual changes in the plant biomass and community composition. The contrasting responses to warming and fertilization treatments show that results from fertilizer addition may not be similar to the effects of increased nutrient mineralization and availability following climatic warming. 相似文献
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Sugar beet leaf homogenate contains Mg2+-stimulated ATPase activity with the highest specific activity in the 25,000–30,000 ×g-fraction. This fraction also has (Na++ K+)-activated ATPase activity. Both activities have two pH optima, one stable at pH 7.9 and one variable at lower pH. When optimal conditions of Na+ and K+ were tested with 64 combinations of these ions, at least two mountains of activity were revealed. The (Na++ K+)-ATPase had a high specificity for ATP. It had lost about 50% of its original activity after 56 days of storage at ?85°C. The activity drop was most pronounced at high ionic concentrations in the test medium. The (Na++ K+)-ATPase shows four peaks of activity when tested at constant ionic strength. The idea is put forward that the four peaks reflect two ATPases, one in the tonoplast and one in the plasmalemma, which undergo conformational changes in relation to the ionic milieu. 相似文献
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Spatial and temporal variation in the biomass and nutrient status of epilithic algae in Lake Erken, Sweden 总被引:3,自引:0,他引:3
MARIA KAHLERT ERS T. HASSELROT HELMUT HILLEBRAND & KURT PETTERSSON 《Freshwater Biology》2002,47(7):1191-1215
1. The aim of this study was to estimate patchiness in biomass and in the internal nutrient status of benthic algae on hard substrata (epilithon) in Lake Erken, Sweden, over different levels of distance, depth and time. Knowledge of the sources and scale of patchiness should enable more precise estimation of epilithic biomass and nutrient status for the entire lake. We focused on the horizontal scale, about which little is known. 2. We sampled epilithon by SCUBA diving and used a hierarchical sampling design with different horizontal scales (cm, dm, 10 m, km) which were nested in two temporal scales (within and between seasons). We also compared two successive years and three sampling depths (0, 1 and 4 m). Biomass was measured as particulate carbon and chlorophyll a (Chl a) and internal nutrient status as carbon : nitrogen : phosphorus (C : N : P) ratios and as specific alkaline phosphatase activity (APA). 3. Horizontal variation accounted for 60–80 and 7–70% of the total variation in biomass and in nutrient status, respectively, at all depths and during both years. Both small and large scales accounted for significant variation. We also found variation with time and depth. Biomass increased in autumn after a summer minimum, and the within‐season variation was very high. The lowest biomass was found at 0 m depth. Both N and P limitation occurred, being higher in 1996 than in 1997 and decreased with depth. 4. As a consequence, any sampling design must address variation with distance, depth and time when estimating biomass or nutrient limitation of benthic algae for an entire lake. Based on this analysis, we calculated an optimal sampling design for detecting change in the epilithic biomass of Lake Erken between different sampling days. It is important to repeat the sampling as often as possible, but also the large scales (10 m and km) and the dm scale should be replicated. Using our calculations as an example, and after a pilot study, an optimal sampling design can be computed for various objectives and for any lake. 5. Short‐term impact of the wind, light and nutrient limitation, and grazing, might be important in regulating the biomass and nutrient status of epilithic algae in Lake Erken. Patchiness in the nutrient status of algae was not coupled to the patchiness of biomass, indicating that internal nutrients and biomass were regulated by different factors. 相似文献
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Phenotypic variation and fluctuating asymmetry in sexually dimorphic feather ornaments in relation to sex and mating system 总被引:2,自引:0,他引:2
JOSÉ JAVIER CUERVO ERS PAPE MØLLER 《Biological journal of the Linnean Society. Linnean Society of London》1999,68(4):505-529
Secondary sexual characters have been hypothesized to demonstrate increased phenotypic variation between and within individuals as compared to ordinary morphological traits. We tested whether this was the case by studying phenotypic variation, expressed as the coefficient of variation (CV), and developmental instability, measured as fluctuating asymmetry (FA), in ornamental and non-ornamental traits of 70 bird species with feather ornamentation while controlling for similarity among species due to common descent. Secondary sexual characters differed from ordinary morphological traits by showing large phenotypic CV and FA. This difference can be explained by the different mode of selection operating on each kind of trait: a history of intense directional (ornaments) and stabilizing selection (non-ornaments). Phenotypic variation is reduced in the sex with more intense sexual selection (males), but does not differ among species with different mating systems. The strength of stabilizing selection arising from natural selection is associated with decreased CV (wing CV is smaller than tarsus or tail CVs). We found evidence of FA being reduced in ornamental feathers strongly affected by aerodynamics (tail feathers) compared to other ornaments, but only in females. In conclusion, CV and FA were not related, suggesting mat phenotypic plasticity and developmental instability are independent components of phenotypic variation. 相似文献
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