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41.
利用采自我国近海的105尾标本,分析了细条天竺鲷、宽条天竺鲷、黑鳃天竺鲷、黑边天竺鲷、垂带天竺鲷、四线天竺鲷、半线天竺鲷、斑鳍天竺鲷等8种天竺鲷属鱼类的矢耳石形态特征。8种鱼类矢耳石前部均较尖,后部略圆钝,背部呈折线状,腹部呈圆弧形,背部中央有缺刻,听沟宽阔;8种鱼耳石长宽比的比值为1.35~1.63,矩形趋近率为0.67~0.77,充实度为14.77~24.99。以上述三种形态学参数为基础进行聚类分析,可将8种鱼类分为3组:细条天竺鲷、宽条天竺鲷、黑边天竺鲷、黑鳃天竺鲷为一组;垂带天竺鲷、四线天竺鲷、半线天竺鲷为一组;斑鳍天竺鲷为一组。耳石听沟边缘走向、宽度以及耳石外部边缘光滑度等轮廓特征在8种天竺鲷属鱼类间呈显著的种间差异。以这些形态特征为基础,编制了8种天竺鲷属鱼类的检索表,检索表表现的种间分类关系特征与聚类分析结果基本一致。  相似文献   
42.
利用平板涂布法从南海海绵生物样品中分离海绵共栖细菌,以枯草芽孢杆菌、金黄色葡萄球菌、大肠杆菌及酿酒酵母作为实验用指示菌对海绵共栖细菌进行了抗菌活性筛选。利用气相质谱联用仪(GC-MS)建立了群体感应信号分子酰基高丝氨酸内酯类化合物(AHLs)的检测方法,分析了活性菌株粗提液中信号分子的产生及种类。同时采用16S rDNA同源性和系统发育分析对活性菌株进行种属鉴定和系统发生学研究。结果表明,在分离到的94株海绵共栖细菌中18株(占19.1%)细菌具有抗菌活性。通过GC-MS检测确定大多数活性菌株都含有AHLs,因此提出了海绵共栖细菌抗菌活性与群体感应之间可能存在必然联系的推测。通过细菌分类鉴定,结果显示具有抗菌活性的细菌大部分属于芽孢杆菌属(Bacillus)。  相似文献   
43.
The morphology and infraciliature of a new marine colepid ciliate, Apocoleps magnus gen. nov., spec. nov., are described based on living observations and silver impregnations. The new genus Apocoleps is characterized by having 8 (vs. 6 in most other related genera) armour tiers, spines at both ends of the cell, 3 adoral organelles and plates with 4 reniform uni-windows. Apocoleps magnus spec. nov. is defined by the following features: body elongated and slightly curved, about 100–120μm× 35–45 μm in vivo; an...  相似文献   
44.
Nine species of Prionospio complex are recorded from China’s waters, including one new species and six newly recorded species. Prionospio (Prionospio) pacifica sp. nov., is characterized by having first and forth pairs of branchiae pinnate, second and third pairs of apinnate, ventral crest on Setiger 9 and dorsal crests on Setigers 10—25. Apoprionospio kirrae (Wilson, 1990), Prionospio (Aquilaspio) convexa Imajima, 1990, Prionospio (Minuspio) multibranchiata Berkeley, 1927, Prionospio (Prionospio) bocki Sderstrm, 1920, Prionospio (Prionospio) dubia Maciolek, 1985 and Prionospio (Prionospio) paradisea Imajima, 1990 are recorded for the first time from China’s waters.  相似文献   
45.
为探究热带西太平洋海山生物多样性,2016年利用"发现"号遥控无人潜水器(ROV)对西太平洋马里亚纳海沟附近的M2海山进行了采样调查,其中获得了3个深水金相柳珊瑚样本。通过光学显微镜和扫描电镜观察,鉴定其为黑发金相柳珊瑚Metallogorgia melanotrichos(WrightStuder,1889)和长刺金相柳珊瑚Metallogorgia macrospina Kükenthal,1919。这两种金相柳珊瑚均为该区域的新记录种,对其作了详细的形态描述,并依据特征性状对该属所有物种作了分类检索。  相似文献   
46.
邢亦谦  邢军武 《海洋科学》2019,43(5):97-102
以纠正碱蓬属Suaeda盐生植物研究中广泛存在的分类错误为目的,针对碱蓬属研究中因缺乏正确的种属鉴定与使用错误种名等导致无法确定研究对象是何植物,使研究结果丧失确定性和科学价值的问题,通过对相关错误文献的梳理,对包括《中国高等植物图鉴》在内的有关碱蓬属植物研究文献进行了初步分析,指出了有关碱蓬属植物研究中的同物异名、同名异物以及中文名与拉丁名错乱等问题并予以纠正。对提高碱蓬属植物研究的科学性与可靠性具有重要参考价值。  相似文献   
47.
太白山北坡成土因素及不同土壤垂直带谱的比较   总被引:1,自引:2,他引:1  
雷梅  陈同斌  冯立  常庆瑞  阎湘 《地理研究》2001,20(5):583-592
在系统地考察太白山北坡地质、地貌、气候和植被等成土因素的基础上,总结和回顾了用土壤发生分类和土壤系统分类两种分类体系划定的太白山北坡土壤垂直带谱。根据最新的土壤系统分类,太白山北坡的土壤垂直带谱是:暗瘠寒冻雏形土(3500~3767m)———暗沃寒冻雏形土(3300~3500m)———酸性湿润雏形土(2500~3300m)———简育湿润淋溶土(1400~2500m)———简育干润淋溶土(<1400m)。分析、比较表明:两种体系有密切联系,均以成土因素为依据,建立在土壤发生学理论之上;与土壤地理发生分类相比,土壤系统分类用可以度量的诊断层和诊断特性进行土壤分类,不仅能够反映出山地土壤成土因素的垂直变化趋势,而且避免了太白山北坡土壤类型鉴定上的许多歧义。  相似文献   
48.
Inoceramid bivalves of the upper Albian and lower Cenomanian of the United States Western Interior are revised, Eleven species-level taxa and three genera are described. Two new species, Gnesioceramus mowriensis, characterizing the Mowry Shale of the early, but not the earliest, Cenomanian, and Posidonioceramus merewetheri, of the lower Cenomanian, and on new genus, Posidonioceramus, are recognised. The Western Interior inoceramid species from this interval are strongly endemic and are not good tools for long-distance correlations, although they are very effective in regional dating.In terms of the inoceramid biostratigraphy, middle and upper parts of the upper Albian can be referred to the Gnesioceramus Biozone, represented by G. comancheanus (Cragin) and G. bellvuensis (Reeside). These taxa are endemic to the Western Interior and some adjacent areas (Gulf Coast; Greenland?), but are closely allied to the cosmopolitan species, Gnesioceramus anglicus (Woods). At approximately the Albian-Cenomanian boundary, the endemic clade of ‘Inoceramus’ nahwisi appears, now referred to the newly erected Posidonioceramus, resulting in a distinct P. nahwisi biozone. This zone corresponds to the lower part of the ammonite Neogastroplites’ stratigraphic range. Gnesioceramids re-appear in the early Cenomanian. Close to base of the Cenomanian, for the first in the Western Interior, the genus Inoceramus, represented by Inoceramus irenensis Warren and Stelck, 1958, apparently immigrated into the Western Interior Basin.The Western Interior inoceramids do not allow for direct correlation to chronostratigraphic standard subdivision. The Albian-Cenomanian boundary, as earlier recognized on geochronologic correlations and confirmed, to some extent, based on ammonites, may approximately be located close to the appearance level of the genus Posidonioceramus.  相似文献   
49.
Abstract. Hydrothermal vent ecosystems have been extensively investigated during the last 20 years; shallow water hot springs (typically found below 50 m depth) have also been studied, and from these ecosystems many thermophilic and hyperthermophilic organisms were isolated and described.
The submarine caves of Cape Palinuro were discovered long ago, but only during the last decades were geological and biological investigations carried out, yielding a large number of reports on this fascinating environment. During the last two years, several samples of water, mud, and/or bacterial mat were collected within the "Grotta Azzurra", and enrichment experiments were performed using peptone, starch, glucose or pullulan as main organic nutrients. Many heterotrophic strains were isolated and most of them grew optimally between 37 and 43 ° C with the addition of 0-2 % NaCl. Growth was usually observed between 10 and 50 ° C the range of growth pH was 4 to 9, and NaCl concentrations up to 10–12 % were tolerated in most cases.
The analysis of 16S rDNA performed with the most representative isolates showed a close phylogenetic relationship with the genera Bacillus, Vibrio, Citrobacter and Escherichia. Moreover, an isolate showing morphological and physiological similarities with the genus Enterococcus was characterised and taxonomically described based on the 16S rDNA sequence.  相似文献   
50.
<正>A new dinosaur Chuxiongosaurus lufengensis gen.et sp.nov.is erected based on a nearly complete skull.The taxon is characterized by the lacrimal perpendicular to the ventral margin of the upper jaw,which is similar to that of Thecodontosaurus;a depression present on the dorsal profile of the snout behind the naris;the rostral profile of the maxilla slopes continuously towards the rostral tip;and the presence of 25 dentary teeth.It also displays prosauropod characters such as a relatively long skull,the slope of the maxillary rostral profile,and teeth that do not have basically constricted crowns.The new specimen is more basal than Anchisaurus and represents the first basal sauropod dinosaur from the Early Jurassic of China.  相似文献   
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