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1.
记述了采自中国西藏的拟遁蛛属1新种:张氏拟遁蛛,新种Pseudopoda zhangi sp.nov.。张氏拟遁蛛,新种Pseudopoda zhangi sp.nov.(图1~5)正模♂,副模1♀,西藏墨脱县背崩乡(29°13′N,95°18′E,海拔2253m),2003-08-08,张锋采;副模2♀♀,西藏墨脱县背崩乡,2003-08-13,张锋采。词源:以采集人的姓氏命名。  相似文献   

2.
中遁蛛属1新种记述(蜘蛛目:巨蟹蛛科)   总被引:3,自引:0,他引:3  
记述产于我国南方的中遁蛛属1新种,滇中遁蛛Sinopoda yunnanensis sp.nov。  相似文献   

3.
本文记述隅蛛属一新种和漏斗蛛属两新种:刺隅蛛,新种Tegenaria aculeata sp.nov.三角漏斗蛛,新种Agelena triangulata sp.nov.,小斑漏斗蛛,新种Agelena micropunetulata sp.nov.。  相似文献   

4.
中国猫蛛属三新种(蜘蛛目,猫蛛科)   总被引:1,自引:0,他引:1  
记述了中国湖南省猫蛛科Oxyopidae猫蛛属Oxyopes 3新种:环缘猫蛛Oxyopes annularis sp.nov.,弓缘猫蛛Oxy-opes arcuatus sp.nov.和带缘猫蛛Oxyopes balteiformis sp.nov.3新种的主要鉴别特征。环缘猫蛛,新种Oxyopes annularis sp.nov.与条纹猫蛛Oxyopes striagntus Song,1991相似,但新种腹部细长,末端特别尖细;外雌器角质化后缘拱起较宽长,呈半圆形,其前缘正中尚有两个小疣突,后者角质化后缘拱起较窄短,呈蛇头状,正中没有成对小疣突。弓形猫蛛,新种Oxyopes arcuatus sp.nov.与尖峰猫蛛Oxyopes jianfeng Song,1991相似,但新种外雌器角质化后缘弯曲呈弓形,近乎半圆,后者条状,近乎平直,仅两侧端稍有弯曲;纳精囊较大,交媾管远端细,弯曲呈圆圈,近端变粗呈漏斗形,后者交媾管粗细均匀,远端平直折向近端。不呈漏斗状。带缘猫蛛,新种Oxyopes balteiformis sp.nov.与细纹猫蛛Oxyopes macilentus L.Koch,1878相似,但新种外雌器角质化后缘呈横向带状,较宽,正中无任何突起结构,后者角质化后缘腹面正中有一个三角形突起,背面观在阴门正中有一个“T”形脊。  相似文献   

5.
记述采自我国江苏省栖霞山和浙江省西天目山蚁微蛛属2新种:胫突蚁微蛛,新种Solenysa pronlrudens sp.nov.和圆斑蚁微蛛, 新种Solenyas circUlaris sp.nov.  相似文献   

6.
记述了分布于江西和海南的拟平腹蛛科2新种:庐山斯托蛛,新种(图1~12)Storenomorpha lushanensis Yu & Chen sp.nov.和海南斯托蛛,新种(图13~24)Storenomorpha hainanensis Jin&Chen sp.nov.。  相似文献   

7.
记述了花冠蛛属Coronilla 2新种,即莽山花冠蛛Coronilla mangshan sp.nov.和炎陵花冠蛛Coronilla yanling sp.nov。  相似文献   

8.
我国南方巨蟹蛛属六新种(蜘蛛目:巨蟹蛛科)   总被引:4,自引:0,他引:4  
本文记述了湖南省、广西壮族自治区、云南省和江西省产的巨蟹蛛属蜘蛛六新种,并绘制有外雌器和触肢器结构图。模式标本保存在湖南省生物研究所。种名:铃形巨蟹蛛新种Hete-ropoda campanacea sp.nov.;鳞片巨蟹蛛,新种Heteropoda squamaceasp.nov.;庐山巨蟹蛛,新种Heteropoda lushanensissp.nov.;细刺巨蟹蛛,新种Heteropoda spiculatasp.nov.;城步巨蟹蛛,新种Heteropoda chengbuensis sp.nov.;锯齿巨蟹蛛,新种Heteropoda serratasp.nov.  相似文献   

9.
首次记述了云南伪遁蛛Pseudopoda yunnanensis(Yang & Hu,2001)的雌蛛,重新绘制了雄蛛触肢器的结构图,并给出了雌雄个体外形图和触肢器、外雌器的数码照片.  相似文献   

10.
我国熊蛛属2新种(蜘蛛目:狼蛛科)   总被引:1,自引:0,他引:1  
报道采自湖南省的熊蛛2新种,分别是:湖南熊蛛Arctosa hunanensis sp.nov.和紫云熊蛛Arctosa ziyunensis sp.nov.。  相似文献   

11.
Research on the influence of sea level variations on the benthic faunas have been carried out in the Upper Ordovician of Sardinia. Study of the depositional facies and sequence analysis of the upper part (Lower Ashgill) of the Portixeddu Formation led to the identification of the sedimentary environments. Cystoids and crinoids are associated to bryozoans and brachiopods in most levels. The numerical analysis of associations and megaguilds shows that crinoids and cystoids have a higher frequency in the proximal and median facies of the upper offshore. The columnal association characterized by Conspectocrinus celticus and the coronoid Mespilocystites tregarvanicus has been discovered in the upper part of the formation. This material and complementary samples from Upper Ordovician of Sardinia and Kabylia (Algeria) bring additional data on the systematic and show the wide distribution of this fauna outside of the Ibero-armorican domain. The distribution of this echinoderm association supports a palaeogeographical position of the Ibero-armorican domain and Sardinia within the north gondwanan margin during the Lower Palaeozoic.  相似文献   

12.
BACKGROUND AND AIMS: The two closely related subtribes Bifrenariinae Dressler and Maxillariinae Benth. are easily distinguished on morphological grounds. Recently, however, molecular techniques have supported the inclusion of Bifrenariinae within a more broadly defined Maxillariinae. The present paper describes the diverse labellar micromorphology found amongst representatives of Bifrenariinae (Bifrenaria Lindl., Rudolfiella Hoehne, Teuscheria Garay and Xylobium Lindl.) and compares it with that found in Maxillaria Pabst & Dungs and Mormolyca Fenzl (Maxillariinae). METHODS: The labella of 35 specimens representing 22 species of Bifrenariinae were examined by means of light microscopy and scanning electron microscopy and their micromorphology compared with that of Maxillaria sensu stricto and Mormolyca spp. The labellar epidermis of representatives of Bifrenaria, Xylobium and Mormolyca was tested for protein, starch and lipids in order to ascertain whether this tissue is involved in the rewarding of pollinators. KEY RESULTS AND CONCLUSIONS: The labella of Bifrenaria spp. and Mormolyca spp. are densely pubescent but those of Xylobium, Teuscheria and Rudolfiella are generally papillose. However, whereas the trichomes of Bifrenaria and Mormolyca are unicellular, those found in the other three genera are multicellular. Hitherto, no unicellular trichomes have been described for Maxillaria, although the labella of a number of species secrete a viscid substance or bear moniliform, pseudopollen-producing hairs. Moniliform hairs and secretory material also occur in certain species of Xylobium and Teuscheria and these genera, together with Maxillaria, are thought to be pollinated by stingless bees (Meliponini). Differences in the labellar micromorphology of Bifrenaria and Mormolyca are perhaps related to Euglossine- and/ or bumble bee-mediated pollination and pseudocopulation, respectively. Although Xylobium and Teuscheria share a number of labellar features with Maxillaria sensu stricto, this does not necessarily reflect taxonomic relationships but may be indicative of convergence in response to similar pollinator pressures.  相似文献   

13.
Phospholipid (PL) and fatty acid composition of chloroplasts of pine needles ( Pinus sylvestris L.) and apple bark tissue ( Malus sylvestris Mill. cv. Golden Delicious) was determined in a series of experiments in which growth temperature and daylength were changed. Trees were exposed to 0 and 20°C and to daylength conditions of 9 and 14 h. All 16 possible combinations were investigated by transfer of the trees from the original condition to each of the other conditions. There was no direct relation between cold hardiness and PL composition in apple bark and pine chloroplasts, when temperature and/or daylength were changed. PL composition seemed to be strongly determined by the sequence of the imposed sets of daylength and temperature. The effect of these environmental factors on PL composition strongly differed from that for cold hardiness. The correlation between the levels of PL (and phosphatidylcholine) and cold hardiness, as reported in the literature, was also evident in this experiment, when treatments, presenting the normal seasonal order, were compared. It seems that the yearly cycle of temperature and daylength is important in determining the PL composition of apple bark and pine chloroplasts.  相似文献   

14.
The postthaw motility and fertility of buffalo and cattle semen is reduced when they are cryopreserved for artificial insemination. In the present study, an attempt was made to characterize the cryogenic changes in proteases and antiprotease activities (APA) of buffalo and cattle semen because these proteolysis regulators have been reported to be associated with sperm motility and fertility. Buffalo sperm demonstrated at least two major proteases of 45 and 42 kDa and three minor proteases of 95, 52, and 33 kDa. Similarly, cattle sperm demonstrated three major proteases of 62, 45, and 42 kDa and two minor proteases of 85 and 78 kDa. Buffalo seminal plasma demonstrated at least three major proteases of 78, 68, and 62 kDa and one minor protease of 98 kDa and cattle seminal plasma demonstrated one major protease of 68 kDa and two minor proteases of 78 and 75 kDa. Except for the 45 kDa protease, most of the previously mentioned proteases were found to be metalloproteinases. Compared with fresh sperm, cryopreserved buffalo and cattle sperm demonstrated a major protease band of 52/49 kDa and the activity of this protease reduced progressively with the duration of cryopreservation. On the contrary, compared with the fresh seminal plasma, cryopreserved buffalo and cattle semen extenders displayed the presence of a new protease band of 45 kDa and demonstrated that this protease activity was leaked from buffalo and cattle cryopreserved spermatozoa. Buffalo and cattle seminal plasmas displayed at least two major APA of 86 and 26 kDa. Compared with buffalo, cattle seminal plasma demonstrated significantly greater APA. Thus, the present study demonstrated the presence of an array of proteases and APA in buffalo and cattle semen and the activities of which changed during cryopreservation. The leakage of the specific protease activity and changes in the proteases and APA might be attributed to reduced motility and fertility of cryopreserved semen in these species.  相似文献   

15.
Abstract

An introduction to the nomenclature and concept of “Romanowsky stains” is followed by a brief account of the dyes involved and especially the crucial role of azure B and of the impurity of most commercial dye lots. Technical features of standardized and traditional Romanowsky stains are outlined, e.g., number and ratio of the acidic and basic dyes used, solvent effects, staining times, and fixation effects. The peculiar advantages of Romanowsky staining are noted, namely, the polychromasia achieved in a technically simple manner with the potential for stain intensification of “the color purple.” Accounts are provided of a variety of physicochemically relevant topics, namely, acidic and basic dyeing, peculiarities of acidic and basic dye mixtures, consequences of differential staining rates of different cell and tissue components and of different dyes, the chemical significance of “the color purple,” the substrate selectivity for purple color formation and its intensification in situ due to a template effect, effects of resin embedding and prior fixation. Based on these physicochemical phenomena, mechanisms for the various Romanowsky staining applications are outlined including for blood, marrow and cytological smears; G-bands of chromosomes; microorganisms and other single-cell entities; and paraffin and resin tissue sections. The common factors involved in these specific mechanisms are pulled together to generate a “universal” generic mechanism for these stains. Certain generic problems of Romanowsky stains are discussed including the instability of solutions of acidic dye–basic dye mixtures, the inherent heterogeneity of polychrome methylene blue, and the resulting problems of standardization. Finally, a rational trouble-shooting scheme is appended.  相似文献   

16.
17.
Restoration and management of riparian ecosystems: a catchment perspective   总被引:10,自引:0,他引:10  
1. We propose that strategies for the management of riparian ecosystems should incorporate concepts of landscape ecology and contemporary principles of restoration and conservation. A detailed understanding of the temporal and spatial dynamics of the catchment landscape (e.g. changes in the connectivity and functions of channel, riparian and terrestrial components) is critical. 2. This perspective is based upon previous definitions of riparian ecosystems, consideration of functional attributes at different spatial scales and retrospective analyses of anthropogenic influences on river catchments. 3. Restoration strategies must derive from a concise definition of the processes to be restored and conserved, recognition of social values and commitments, quantification of ecological circumstances and the quality of background information and determination of alternatives. 4. The basic components of an effective restoration project include: clear objectives (ecological and physical), baseline data and historical information (e.g. the hydrogeomorphic setting and the disturbance regime), a project design that recognizes functional attributes of biotic refugia, a comparison of plans and outcomes with reference ecosystems; a commitment to long-term planning, implementation and monitoring and, finally, a willingness to learn from both successes and failures. 5. Particularly important is a thorough understanding of past natural disturbances and human-induced changes on riparian functions and attributes, obtained by a historical reconstruction of the catchment.  相似文献   

18.
Coevolutionary interactions are thought to play a crucial role in diversification of hosts and parasitoids. Furthermore, resource availability has been shown to be a fundamental driver of species diversity. Yet, we still do not have a clear understanding of how resource availability mediates the diversity generated by coevolution between hosts and parasitoids over time. We used experiments with bacteria and bacteriophage to test how resources affect variation in the competitive ability of resistant hosts and temporal patterns of diversity in the host and parasitoid as a result of antagonistic coevolution. Bacteria and bacteriophage coevolved for over 150 bacterial generations under high and low-resource conditions. We measured relative competitive ability of the resistant hosts and phenotypic diversity of hosts and parasitoids after the initial invasion of resistant mutants and again at the end of the experiment. Variation in relative competitive ability of the hosts was both time- and environment-dependent. The diversity of resistant hosts, and the abundance of host-range mutants attacking these phenotypes, differed among environments and changed over time, but the direction of these changes differed between the host and parasitoid. Our results demonstrate that patterns of fitness and diversity resulting from coevolutionary interactions can be highly dynamic.  相似文献   

19.
The stone fruit genus Prunus, within the family Rosaceae, comprises more than 230 species, some of which have great importance or value as ornamental or fruit crops. Prunus are affected by numerous viruses and viroids linked to the vegetative propagation practices in many of the cultivated species. To date, 44 viruses and three viroids have been described in the 9 main cultivated Prunus species. Seven of these viruses and one viroid have been identified in Prunus hosts within the last 5 years. This work addresses recent advances and prospects in the study of viruses and viroids affecting Prunus species, mostly concerning the detection and characterisation of the agents involved, pathogenesis analysis and the search for new control tools. New sequencing technologies are quickly reshaping the way we can identify and characterise new plant viruses and isolates. Specific efforts aimed at virus identification or data mining of high‐throughput sequencing data generated for plant genomics‐oriented purposes can efficiently reveal the presence of known or novel viruses. These technologies have also been used to gain a deeper knowledge of the pathogenesis mechanisms at the gene and miRNA expression level that underlie the interactions between Prunus spp. and their main viruses and viroids. New biotechnological control tools include the transfer of resistance by grafting, the use of new sources of resistance and the development of gene silencing strategies using genetic transformation. In addition, the application of next generation sequencing and genome editing techniques will contribute to improving our knowledge of virus–host interactions and the mechanisms of resistance. This should be of great interest in the search to obtain new Prunus cultivars capable of dealing both with known viruses and viroids and with those that are yet to be discovered in the uncertain scenario of climate change.  相似文献   

20.
Zinc and manganese loading into developing wheat grain is little understood at present. The objective of this work was to investigate factors that may affect the rate of transport of Zn and Mn into developing wheat grain of cultured ears. Ears 18-22 days post-anthesis were cultured in solutions containing labelled Zn and Mn. The effect of additions of Cu, Fe, citrate, malate and EDTA to the culture solution was observed. The effect of humidity and awn removal as well as the sucrose status of the ears on Zn and Mn transport was also investigated. The effect of high concentration of Zn and Mn on [14C]-sucrose transport was determined. High humidity almost completely blocked transport of Zn and Mn into the grain. Awn removal reduced the transport of Zn and Mn to the lemma but not the grain. When the ears were depleted of sucrose (by maintaining them in the dark prior to labelling) transport of Zn and Mn to the grain was reduced compared to ears cultured with sucrose. The presence of Cu reduced the loading of Zn into the grain. There was little effect of Cu on Mn transport or Fe on either Zn or Mn transport. High concentrations of Zn and Mn in the culture solution did not affect [14C]-sucrose loading into the grain but loading of Zn and Mn was limited at high concentrations suggesting membrane saturation. This study demonstrates that sucrose status and humidity clearly influence the transport of Zn and Mn into the grain, and that other ions may influence Zn and Mn transport.  相似文献   

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