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11.
Two new species of micropterigids, Vietomartyria nankunshana Hirowatari & Hashimoto sp. nov. and V. nanlingana Hirowatari & Jinbo sp. nov., are described from Nankunshan and Nanling (Guangdong, China), respectively. The genus Vietomartyria Hashimoto & Mey, 2000, which was originally established as a monotypic genus, is redefined based on the following autapomorphies shared by the three species: (i) the long basal stalk of each flagellomere; (ii) the many (>100) minute serrate projections near the gonopore of aedeagus; and (iii) the gonopore situated dorsally near the apex.  相似文献   
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SYNOPSIS. The reorganization in resting cysts which produce a single emerging individual was followed in 5 species of Colpodidae forming a possible evolutionary series with increasing numbers of kineties. Stomatogenesis in Colpoda maupasi and C. inflata was studied for the first time; that in C. steinii, C. cucullus and Tillina magna was reinvestigated with new observations. In all, the oral primordium is double and originates from segments of certain somatic kineties, constant for each species. The larger mouthparts in the larger ciliates are produced from a correspondingly greater number of kineties. Morphogenetic and evolutionary implications of this series of observations are discussed.  相似文献   
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A key is provided to both sexes of the four species of Pontomyia; cottoni Womersley, natans Edwards, oceana Tokunaga, pacifica Tokunaga. This genus is widespread in the western Pacific Ocean. Adult females are vermiform. Adult males have normal halteres but reduced wings; they are unusual among Chironomidae in having bare, not plumose antennae.  相似文献   
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Forest inventories from the intact rainforests of the Amazon indicate increasing rates of carbon gain over the past three decades. However, such estimates have been questioned because of the poor spatial representation of the sampling plots and the incomplete understanding of purported mechanisms behind the increases in biomass. Ecosystem models, when used in conjunction with satellite data, are useful in examining the carbon budgets in regions where the observations of carbon flows are sparse. The purpose of this study is to explain observed trends in normalized difference vegetation index (NDVI) using climate observations and ecosystem models of varying complexity in the western Amazon basin for the period of 1984–2002. We first investigated trends in NDVI and found a positive trend during the study period, but the positive trend in NDVI was observed only in the months from August to December. Then, trends in various climate parameters were calculated, and of the climate variables considered, only shortwave radiation was found to have a corresponding significant positive trend. To compare the impact of each climate component, as well as increasing carbon dioxide (CO2) concentrations, on evergreen forests in the Amazon, we ran three ecosystem models (CASA, Biome‐BGC, and LPJ), and calculated monthly net primary production by changing a climate component selected from the available climate datasets. As expected, CO2 fertilization effects showed positive trends throughout the year and cannot explain the positive trend in NDVI, which was observed only for the months of August to December. Through these simulations, we demonstrated that the positive trend in shortwave radiation can explain the positive trend in NDVI observed for the period from August to December. We conclude that the positive trend in shortwave radiation is the most likely driver of the increasing trend in NDVI and the corresponding observed increases in forest biomass.  相似文献   
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Two new species of Petunia (Solanaceae) from southern Brazil   总被引:1,自引:0,他引:1  
Two new species of Petunia Jussieu from Santa Catarina and Rio Grande do Sul states in Brazil are described and compared with the other seven specieS. A key and synopsis of all the species of Petunia are provided  相似文献   
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Of fragments involving a partial removal of the original adoral zone of membranelles (AZM), the monomacro-nucleate ones become reorganized monostomes resulting from a simple fusion of the remnant AZM to the oral primordium induced, and the binucleate ones become dividers by initiation of the oral primordium posteriorly from the posterior terminal of the remnant AZM. The cirral primordium in any fragment arises alongside its corresponding oral area. Weisz's idea of the dominance and inhibition of the original oral system extending over the oral primordium site is applicable in stomatogenesis of the present species. This application is found also in cirral formation.
In fragments from early stage dividers, a formed oral primordium is easily absorbed by influence of the intact original AZM. This event also occurs after complete removal of the AZM. Such results led to the hypothesis that the oral primordium in the normal divider may be formed under some stoma-togenic activation of the AZM followed by escape from inhibition also arising from the same source. Irrevocable furrow formation and irreversibility of the oral primordium in stomatogenesis occur in later stages of division. Nevertheless division in these stages is blocked when certain operations are performed, forming monsters possessing the AZM of the opisthe translocated to the side opposite to that of the proter. In other monsters obtained from a fusion of the AZM of the proter to that of the opisthe, division occurs belatedly, prior to which secondary oral and cirral primordia are produced.  相似文献   
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蝉作为中药材,在中国已有悠久的应用历史。中国国内市场流通的蝉蜕基源动物常见为10种。在种类部分提供了各分类阶元的鉴别特征。绘制了蝉蜕的触角和前足的特征图。  相似文献   
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