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121.
正Brackish and saline lakes are common in the arid zones of the Earth.They are unique ecosystems with extremely high p H values and high mineralization levels(up to saturating concentrations).These lakes are inhabited by 相似文献
122.
Well-preserved specimens of Kepingophyllum aksuence Wu et Chow were collected from Early Permian strata in western Tarim Basin, Xinjiang. More than 100 serial thin sections were made for this study. Kepingophyllum aksuence displays a unique increase pattern. The bud appears in lonsdaleoid dissepiments between the corallites where the wall of parent corallite disappears and the area becomes aphroid. This increase pattern is different from other lateral increases of most colonial rugose corals, and therefore has taxonomic significance to differentiate Kepingophyllidae from other compound rugose corals. It is also discussed that Kepingophyllum aksuence has a high “reproductive integration”, which means a rapid growth of buds during the offsetting process. Kepingophyllum was possibly originated from Ivanovia and was also a probable ancestor of Wentzellophyllum, which is supported here by more or less the similarity of the blastogeny in different stages of three taxa. 相似文献
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124.
以采自中国海域12种石斑鱼标本为基础,分析了石斑鱼属(Epinephelus)鱼类的矢耳石形态特征,探讨了耳石形态在该属鱼种识别方面的应用。结果显示,12种鱼类矢耳石形态近似,耳石细长,呈三角形或梭形,由听沟开口处形成的前部凹刻"V"形或浅宽,形成显著或不显著的侧叶。12种鱼耳石长宽比1.76~2.41,矩形趋近率0.60~0.72,充实度17.24~36.58。耳石外部轮廓、边缘光滑度、听沟前部形态、凹刻类型等特征同是本属鱼种耳石形态识别的主要依据,基于傅里叶系数的聚类分析结果表明耳石形态种间分异较显著。结果表明,听沟同是石斑鱼属鱼类耳石形态分类的重要特征之一,根据耳石形态可以实现石斑鱼属鱼种的初步分类检索,耳石形态在鱼类系统分类上有良好的应用研究前景。 相似文献
125.
已知多丝藻科(索藻目,褐藻门)约有50种,我国仅仅报道2种。记述多丝科的美丝藻属Compsonema、小孢藻属Microsponigum和原水云属Protectocarpus等3个中国新记录属,以及球状美丝藻Compsonema coniferum、多线美丝藻C.myrionematoides、匍匐美丝藻C.serpens、放射百丝藻Hecatonema diffusum、繁育百丝藻H.distromatica、初级百丝藻H.primarium、球形小孢藻Microspongium globosum、考氏多丝藻Myrionema corunnae、原水云Protectocarpus speciosus等9种中国新记录种。研究的标本采集于中国海区,保存在中国科学院海洋研究所海洋生物标本馆(AST)。 相似文献
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127.
近2~3年来,陕西省考古研究院科研人员再次对蓝田县的新街遗址进行了抢救性发掘,经过清理整理,发现于新街遗址灰坑、探沟和探方中的全新世鸟类骨骼共70件.鸟类化石均为分散保存骨骼,但此次发现的鸟类骨骼保存不仅数量多,而且形态也较完好,是国内全新世鸟类化石发现记录所罕见的.本文记述了对这批鸟类化石开展形态解剖学的鉴定,并系统完成分类学研究的成果,新街遗址中总计鸟类所属8目、8科、8属,共9种,其中以水生鸟类居多.此外,根据鸟类的生存习性及鸟类骨骼上残存的人工痕迹,还针对新街遗址全新世时期的环境和古人类的生活行为进行了全方位多角度的分析和推理,为新街遗址在传统考古学研究的基础上提供了全新的科学信息和有益的补充. 相似文献
128.
WANG Chunguang HUANG Jiaqi XIANG Peng WANG Yanguo XU Zhenzu GUO Donghui LIN Mao 《海洋学报(英文版)》2014,33(6):95-102
Fifty-seven stations(48 grid stations and nine stratified stations) were sampled across the study region(67.000°–88.394°N, 152.500°–178.643°W) during the 4th Chinese National Arctic Research Expedition(CHINARE 4) from July to August 2010 by the icebreaker R/V Xuelong. A total of 24 species of Hydromedusae were identified from 130 zooplankton samples, of which seven species belonged to Automedusa, eight species to Anthomedusae, four species to Leptomedudae, and three species to Siphonophora. Catablema multicirratum Kishinouye, 1910, Bougainvillia bitentaculata Uchida, 1925, and Euphysa japonica(Maas, 1909) were recorded for the first time in the Arctic sea. In the present paper, 18 species of Hydromedusae were described and illustrated, of which three species were described for the first time in the Arctic sea, and 15 species were described for the first time in China. 相似文献
129.
《青岛海洋大学学报(英文版)》2014,(2):283-289
Acila divaricata (Hinds, 1843) and A. mirabilis (Adams and Reeve, 1850) are common benthic bivalves in China. A number of researchers have proposed that the latter species is a junior synonym of the former species. Because of morphological similarities, it is difficult to distinguish these two species based on visual examination only. For better understanding of their taxon-omy, the mitochondrial CO1 gene fragments of five individuals of A. divaricata from the East China Sea and six individuals of A. mirabilis from the Yellow Sea were sequenced in this study. The phylogenetic relationships of the obtained COI sequences, together with nineteen sequences of three species of the genus Nucula, were analyzed. The pairwise intra- and inter-specific distances for the CO1 sequences ranged from 0.002 to 0.017 and from 0.128 to 0.134, respectively, and no overlap was found. Phylogenetically, A. divaricata and A. mirabilis form distinct clades and cluster into a sister to all other Nucula species. The results indicated that A. di-varicata and A. mirabilis are two distinct species. The differences in the morphology and distribution between the two species were briefly discussed. 相似文献
130.
Acila divaricata (Hinds, 1843) and A. mirabilis (Adams and Reeve, 1850) are common benthic bivalves in China. A number of researchers have proposed that the latter species is a junior synonym of the former species. Because of morphological similarities, it is difficult to distinguish these two species based on visual examination only. For better understanding of their taxonomy, the mitochondrial COI gene fragments of five individuals of A. divaricata from the East China Sea and six individuals of A. mirabilis from the Yellow Sea were sequenced in this study. The phylogenetic relationships of the obtained COI sequences, together with nineteen sequences of three species of the genus Nucula, were analyzed. The pairwise intra- and inter-specific distances for the COI sequences ranged from 0.002 to 0.017 and from 0.128 to 0.134, respectively, and no overlap was found. Phylogenetically, A. divaricata and A. mirabilis form distinct clades and cluster into a sister to all other Nucula species. The results indicated that A. divaricata and A. mirabilis are two distinct species. The differences in the morphology and distribution between the two species were briefly discussed. 相似文献