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991.
Summary. Taxonomic update and geographic distribution of fleas of the genus Ctenophthalmus Kolenati 1856 in the Western Palearctic Region (Insecta: Siphonaptera: Ctenophthalmidae). Among fleas (Siphonaptera), the genus Ctenophthalmus is the one that comprises the largest number of taxa and is also characterized by a large geographical range. Here, we present a taxonomic revision of the Western Paleartic subgenera, groups, species and subspecies. We recognized a total of 143 taxa (57 species and 86 subspecies). These taxa are clustered into 23 groups of species, which fall into seven of the 16 subgenera of the genus Ctenophthalmus. According to Hopkins & Rothschild (1966), the subgenus Ctenophthalmus would only include the agyrtes group, itself divided into subgroups. We decided to raise these subgroups to group status to clarify taxonomic relationships within the subgenus Ctenophthalmus. Within this subgenus, the arvernus group is renamed baeticus, the fransmiti group is confirmed, and the egregius group is created. For each taxon, we provided information on geographical distribution, mammalian hosts, and host specificity. 相似文献
992.
The genus Thermistis Pascoe 1867 is revised. T. croceocincta conjunctesignata Rondon & Breuning 1971 is upgraded to a species and newly recorded from China and Myanmar. T. xanthomelas Holzschuh 2007 is newly recorded from Vietnam, Laos and Myanmar. T. sulphureonotata Pu 1984 is newly recorded from Vietnam and Laos. Three new species are described from China: T. hainanensis Lin & Yang n. sp. from Hainan Island, T. kaiyuni Chou & Kurihara n. sp. from Taiwan Island and T. cheni Lin & Chou n. sp. from Yunnan and Sichuan provinces. Photographs of habitus and terminalia and a key to the eleven valid species of Thermistis are presented. 相似文献
993.
LISE COMTE LAËTITIA BUISSON MARTIN DAUFRESNE GAËL GRENOUILLET 《Freshwater Biology》2013,58(4):625-639
1. Climate change could be one of the main threats faced by aquatic ecosystems and freshwater biodiversity. Improved understanding, monitoring and forecasting of its effects are thus crucial for researchers, policy makers and biodiversity managers. 2. Here, we provide a review and some meta‐analyses of the literature reporting both observed and predicted climate‐induced effects on the distribution of freshwater fish. After reviewing three decades of research, we summarise how methods in assessing the effects of climate change have evolved, and whether current knowledge is geographically or taxonomically biased. We conducted multispecies qualitative and quantitative analyses to find out whether the observed responses of freshwater fish to recent changes in climate are consistent with those predicted under future climate scenarios. 3. We highlight the fact that, in recent years, freshwater fish distributions have already been affected by contemporary climate change in ways consistent with anticipated responses under future climate change scenarios: the range of most cold‐water species could be reduced or shift to higher altitude or latitude, whereas that of cool‐ and warm‐water species could expand or contract. 4. Most evidence about the effects of climate change is underpinned by the large number of studies devoted to cold‐water fish species (mainly salmonids). Our knowledge is still incomplete, however, particularly due to taxonomic and geographic biases. 5. Observed and expected responses are well correlated among families, suggesting that model predictions are supported by empirical evidence. The observed effects are of greater magnitude and show higher variability than the predicted effects, however, indicating that other drivers of changes may be interacting with climate and seriously affecting freshwater fish. 6. Finally, we suggest avenues of research required to address current gaps in what we know about the climate‐induced effects on freshwater fish distribution, including (i) the need for more long‐term data analyses, (ii) the assessment of climate‐induced effects at higher levels of organisation (e.g. assemblages), (iii) methodological improvements (e.g. accounting for uncertainty among projections and species’ dispersal abilities, combining both distributional and empirical approaches and including multiple non‐climatic stressors) and (iv) systematic confrontation of observed versus predicted effects across multi‐species assemblages and at several levels of biological organisation (i.e. populations and assemblages). 相似文献
994.
995.
掌握种群动态以及迁徙习性对濒危候鸟的保护至关重要。2004~2005、2007~2008、2008~2009年的冬季(10月~次年4月),采用夜栖地直接计数法对云南省纳帕海湿地黑鹳(Ciconia nigra)的种群数量进行了监测。结果表明,在2004~2005、2007~2008、2008~2009年冬季,纳帕海湿地越冬黑鹳种群平均数量分别为39.6、128.6、181.8只,呈逐年增加的趋势;通常黑鹳10月下旬迁来,至次年3月中下旬迁离;纳帕海同时也是繁殖于蒙古国的黑鹳迁往印度越冬地的重要停歇地,过境时间集中在 11月中上旬。纳帕海湿地已经成为国内最为重要的黑鹳越冬地和迁徙停歇地,建议当地管理部门加强湿地管理,维持适当的浅水区域作为黑鹳的觅食地,另外需加强旅游管理,减少游客对黑鹳的干扰。 相似文献
996.
Capsule Timing of breeding influenced wing-length at fledging, and egg size may be an indicator of fledging weight and the amount of food received by chicks. Aims To investigate chick growth, temporal patterns of chick food provisioning and the importance of indices of parental condition or quality, egg size and hatching date, to predict nestling body mass and wing-length at fledging, and compare breeding and chick feeding characteristics between colonies in the northeast Atlantic. Methods A survey of Cory's Shearwater nests was carried out at Vila islet. A sample of 52 chicks, ringed and weighed at hatching, was selected to study chick growth and food provisioning. Results Hatching success (51%) was much lower than fledging success (87%). Both hatching date and egg size contributed to explain wing-length at fledging, but hatching date, which was negatively correlated with wing-length at fledging, had the most important contribution (22%). There was some indication that egg size may explain variation in fledging weight and the amount of food received by chicks. Food delivery and feeding frequency of chicks varied throughout the chick development stage and three phases were distinguished: (1) 0–29 days, the highest feeding frequency values and a linear increase in food delivery; (2) 30–69 days, an oscillation in food delivery and medium feeding frequencies; (3) 70–90+ days, a sharp decrease in both food delivery and feeding frequency. Conclusion Variation in food availability did not seem sufficient to override the overall importance of indices of parental quality in determining reproductive measures and chick provisioning. Breeding and feeding characteristics were similar between colonies in the northeast Atlantic, with variability in chick provisioning higher further south. 相似文献
997.
998.
Pretreatment of rice straw by using renewable cholinium amino acids ionic liquids ([Ch][AA] ILs)‐water mixtures and the subsequent enzymatic hydrolysis of the residues were conducted in the present work. Of the eight mixtures composed of ILs and water, most were found to be effective for rice straw pretreatment. After pretreatment with 50% ILs‐water mixtures, the enzymatic digestion of the lignocellulosic biomass was enhanced significantly, thus leading to satisfactory sugar yields of >80% for glucose and approximately 50% for xylose. To better understand the ILs pretreatment mechanism, confocal laser scanning microscopy combined with immunolabeling and transmission electron microscopy were used to visualize changes in the contents and distribution of two major components—lignin and xylan. The results coupled with changes in chemical structures (infrared spectra) of the substrates indicated occurrence of extensive delignification, especially in cell corner and compound middle lumen of cell walls, which made polysaccharides more accessible to enzymes. This pretreatment process is promising for large‐scale application because of the high sugar yields, easy handling, being environmentally benign and highly tolerant to moisture, and significantly reduced cost and energy consumption. Biotechnol. Bioeng. 2013; 110: 1895–1902. © 2013 Wiley Periodicals, Inc. 相似文献
999.
1000.