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1.
《Geobios》2014,47(5):315-324
A new genus and species of male cones of coniferophyte from the Lower Permian (Artinskian and Kungurian) deposits of the Urals, Russia is described: Uralostrobus voltzioides Naugolnykh nov. gen., nov. sp. The cone shows characters typical of some representatives of conifers belonging to the order Voltziales: more or less isometrical bracts of rhombic shape, prolonged sporangia with attenuate apices, and bisaccate pollen of Illinites-type. General information on the associated female seed scales and vegetative leafy shoots is given as well. 相似文献
2.
Actinidia chlorotic ringspot‐associated virus: a novel emaravirus infecting kiwifruit plants 下载免费PDF全文
Yazhou Zheng Beatriz Navarro Guoping Wang Yanxiang Wang Zuokun Yang Wenxing Xu Chenxi Zhu Liping Wang Francesco Di Serio Ni Hong 《Molecular Plant Pathology》2017,18(4):569-581
By integrating next‐generation sequencing (NGS), bioinformatics, electron microscopy and conventional molecular biology tools, a new virus infecting kiwifruit vines has been identified and characterized. Being associated with double‐membrane‐bound bodies in infected tissues and having a genome composed of RNA segments, each one containing a single open reading frame in negative polarity, this virus shows the typical features of members of the genus Emaravirus. Five genomic RNA segments were identified. Additional molecular signatures in the viral RNAs and in the proteins they encode, together with data from phylogenetic analyses, support the proposal of creating a new species in the genus Emaravirus to classify the novel virus, which is tentatively named Actinidia chlorotic ringspot‐associated virus (AcCRaV). Bioassays showed that AcCRaV is mechanically transmissible to Nicotiana benthamiana plants which, in turn, may develop chlorotic spots and ringspots. Field surveys disclosed the presence of AcCRaV in four different species of kiwifruit vines in five different provinces of central and western China, and support the association of the novel virus with symptoms of leaf chlorotic ringspots in Actinidia. Data on the molecular features of small RNAs of 21–24 nucleotides, derived from AcCRaV RNAs targeted by host RNA silencing mechanisms, are also reported, and possible molecular pathways involved in their biogenesis are discussed. 相似文献
3.
4.
记述中国象蜡蝉科(半翅目:蜡蝉总科)1新属:滕象蜡蝉属 Dictyotenguna gen. n.,其模式种为周氏滕象蜡蝉 Dictyotenguna choui sp. nov..简要介绍了东洋界和东古北界象蜡蝉系统学发展概况。模式标本保存于中国科学院动物研究所国家动物博物馆。 相似文献
5.
采用硅胶柱色谱、凝胶柱色谱及其他分离手段从甘西鼠尾草中分离得到12个化合物,根据化合物理化性质和波谱数据分别鉴定为:丹参酮ⅡA(1)、丹参酮Ⅰ(2)、丹参内酯(3)、隐丹参酮(4)、丹参酸甲酯(5)、间羟基苯甲醛(6)、迷迭香酚(7)、异迷迭香酚(8)、紫丹参甲素(9)、紫丹参乙素(10)、二氢丹参酮Ⅰ(11)、丹参新醌甲(12)。其中化合物7、8为首次从该植物中分离得到,化合物6为首次从该属植物分离得到。 相似文献
6.
During a study carried out on the subfamily Exogoninae (Syllidae) from Australia, several specimens of a new genus and species were found in samples of dead coral substrate from Western Australia. They have long palps, fused except for a terminal notch, long median and two short lateral antennae, a single pair of short tentacular cirri, and short dorsal cirri, somewhat longer than the parapodial lobes. These characters resemble those of the genus Exogone Örsted, 1845. However, all these appendages are articulated. The chaetae are very similar to those of several species of Syllis Lamarck, 1818, having coarse spines on the margin of compound chaetal blades and truncated dorsal simple chaetae. Furthermore, the pharynx begins in chaetiger 3, posterior to the peristomium, as in many species of the genus Syllis; this condition does not occur in any described species of Exogone. The new genus is provisionally proposed to belong to the subfamily Syllinae, although it has some characters typical of the Exogoninae. Examination under the SEM shows another peculiar feature, the nuchal organs are distinctly laterally located. Within the Syllinae, only Paratyposyllis Hartmann-Schröder, 1962 has a single pair of tentacular cirri, but in that genus, the palps are only basally fused. 相似文献
7.
作者系统整理了中国五节根蚜亚科Fordinae标本,发现2新属:离倍蚜属DimelaphisZhang,gen.nov.和拟孕蚜属SicifordaZhng,gen.nov.;5新种:榆钱毛根蚜ChaetogeolcaulmidrupaZhang,sp.nov,钝镰离倍蚜D.obtusifalcataZhang,sp.nov,金黄五节根蚜FordaauralentaZhngetQiao,sp.nov,毛多五节很蚜F.multicomaZhng,sp.nov.及六节拟孕蚜S.sexiarticulataZhang,sp.nov.二新亚种:麦拟根蚜沾化亚种ParacletuscimicformiszhanhuanusZhng,ssp.nov。模式标本保存在中国科学院动物研究所。 相似文献
8.
记述了云南曲靖潇湘区关底组(志留系罗德洛统)真盔甲鱼类一新属、新种——长孔盾鱼(Dunyu longiforus gen.et sp.nov.),丰富了以梦幻鬼鱼为代表的潇湘脊椎动物群的组成.该新属具真盔甲鱼科的鉴别特征:后眶上管和中背管二者连续过渡,后端两侧辏合呈“U”字形,侧背管仅发出3条侧横管.新属内角缺如,这一特征过去在真盔甲鱼科中仅见于真盔甲鱼属.新属区别于真盔甲鱼属的主要特征有:角向后方延伸,呈棘状或叶状;头甲最宽处位于角末端之前,宽长比小于1.1;中背孔末端超越眶孔后缘连线.基于对秀山真盔甲鱼头甲标本的重新观察,将秀山真盔甲鱼归入盾鱼属.新种区别于秀山盾鱼(Dunyu xiushanensis)的特征有:个体较大,头甲长大于宽;角呈棘状;眶孔位置相对靠前,头甲眶前区与眶后区的长度之比小于0.75;多边形崮状瘤点,较大,长可超过2 mm. 相似文献
9.
Choristopsychidae, established by Martynov in 1937 with a single isolated forewing, is a little known extinct family in Mecoptera. Since then, no new members of this enigmatic family have been described. Based on 23 well-preserved specimens with complete body and wings from the Middle Jurassic of northeastern China, we report one new genus and three new species of Choristopsychidae, two new species of the genus Choristopsyche Martynov, 1937: Choristopsyche perfecta
sp. n. and Choristopsyche asticta
sp. n.; one new species of Paristopsyche
gen. n.: Paristopsyche angelineae
sp. n.; and re-describe Choristopsyche tenuinervis Martynov, 1937. In addition, we emend the diagnoses of Choristopsychidae and Choristopsyche. Analyzing the forewing length/width ratios of representative species in Mecoptera, we confirm that choristopsychids have the lowest ratio of forewing length/width, meaning broadest forewings. These findings, the first fossil choristopsychids with well-preserved body structure and the first record of Choristopsychidae in China, shed light on the morphology of these taxa and broaden their distribution from Tajikistan to China, while increasing the diversity of Mesozoic Mecoptera in China. 相似文献
10.
Abstract Two new species of the grasshopper family Catantopidae were discovered from the Mangshan National Natural Reserve at the southern tip of Hunan Province. One of them constitutes a new genus, Yiniu , which is close to Oxya Audinet-Serville. They are described as below. 相似文献