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芍药属牡丹组的分类历史和分类处理 总被引:95,自引:7,他引:95
芍药属Paeonia木本类群,即牡丹组sect.Moutan DC.,为中国特有;广泛栽培的牡丹也起源于
中国。遗憾的是我国学者对牡丹类群的分类一直未予重视,野生类群的标本也很少。90年代以来对该
类群的分类突然热起来,中外学者连续发表了多个新种、新亚种和新等级,但仍然没有一个全面的修订。
在美国地理学会基金资助下,我们几乎踏遇了该类群分布区的各个角落,拜访了所有模式产地(仅一个
例外),对64个居群进行了考察和取样。在性状分析的基础上检查了各个分类群的问题,考证了全部模
式,最后对该类群作出分类修订。本文是对分类历史的回顾,并表述了我们的分类处理:牡丹组共有8个种,其中3个种各包含两个亚种,另有两个杂种。 相似文献
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中国荩草属叶片表皮的微形态及其分类意义 总被引:2,自引:0,他引:2
本文报道荩草属及其邻近属共5属17种4变种的叶片表皮微形态研究,其中有些种类为首次报道。主要有以下几点: 1、荩草属叶片表皮微形态有5种类型,根据这几种类型结合小穗的外部形态,可在荩草属下分为两亚属及5个组。 2、荩草属及其哑铃形的硅细胞及三角形或圆屋顶形的气孔副卫细胞等近似须芒草属Andropogon Linn.应位于禾本科Gramineae蜀黍族Andropogoneae下,但硅细胞多为短哑铃形而且伴有其它各种类型,微毛的顶细胞远长于基细胞的独特性状,应独立成为荩草亚族Arthraxoninae Benth。 3、根据A.breviaristatus Hack.,A.quartiniana A. Rich.,A.pauciflorus Honda and A.hispidus(Thunb.)Makino 4者叶片表皮细胞类型完全相似特征,赞同P.C.van Weltzen意见,应作一种处理;根据国际命名法规优先律,应用A.hispidus (Thunb.) Makino。 4、海南荩草A. hainanensis Keng et S.L.Chen与茅坪荩草A. maopingensis S.L.Chen et Y.X.Jin应当独立成种.因其两种的叶片表皮细胞类型完全不同。 相似文献
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中国榆属花粉形态研究及其分类意义 总被引:3,自引:0,他引:3
用光学显微镜和扫描电镜观察了榆属(Ulmus L.)5个组中19个种的花粉形态,并对我国具有的4组15种进行了统计学观测,对个别种的花粉外壁作了透射电镜超微结构研究。该属花粉萌发孔为4—7个,因种而异,分别为4—5、4—6和4—7孔。不同孔数的花粉含量存在差异。花粉外壁纹饰可区分为疣状、条块状、脑纹状、粗拟网状和细拟网状等5种主要类型。外壁超微结构表明,该属花粉无典型柱状层的分化。并就一些属内有关的分类学问题进行了讨论。 相似文献
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关于双形藻属和韦氏藻属的分类位置问题 总被引:2,自引:0,他引:2
到目前为止,绿球藻目(Chlorococcales)的分类系统是相当混乱的。要整理这一目植物的分类系统,作者认为:首先要建立这一目的分类基础,同时,还要对于在分类系统上作为基本单位的属,尤其是在特征上不明确的,加以整理 相似文献
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本研究检视了采自中国沿海的银口天竺鲷属标本314尾, 形态学鉴定为8种: 斑鳍银口天竺鲷(Jaydia carinata (Cuvier, 1828 ))、细条银口天竺鲷(J. lineata (Temminck & Schlege, 1842))、新几内亚银口天竺鲷(J. novaeguineae (Valenciennes, 1832))、黑鳃银口天竺鲷(J. poeciloptera (Cuvier, 1828 ))、史密斯氏银口天竺鲷(J. smithi Kotthaus 1970)、横带银口天竺鲷(J. striata (Smith & Radcliffe, 1912 ))、印度洋银口天竺鲷(J. striatodes (Gon, 1997 ))和黑边银口天竺鲷(J. truncata (Bleeker, 1854 ))。结合GenBank中的同种序列, 对史密斯氏银口天竺鲷进行DNA条形码分析, 发现中国群体和地中海群体分为两个组群, 两者平均组间遗传距离为0.044, 表明其中存在隐存种。因该种模式产地为亚丁湾, 推测中国种群为隐存种Jaydia sp.。结合标本和文献考证, 我们认为中国已知有银口天竺鲷属鱼类9种, 未采集到的烟台银口天竺鲷J. tchefouensis (Fang, 1942 )可能为J. lineata次定同种异名。我们整理了各种的同种异名、形态特征和地理分布, 编制了检索表, 探讨了分类问题, 修订了错误。中国已记录物种J. ellioti、J. arafurae、J. albomarginata实际为J. truncata、J. poeciloptera和J. novaeguineae。 相似文献
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Marcelo R. Sánchez‐Villagra Hendrik Müller Christopher A. Sheil Torsten M. Scheyer Hiroshi Nagashima Shigeru Kuratani 《Journal of morphology》2009,270(11):1381-1399
We investigated the development of the whole skeleton of the soft‐shelled turtle Pelodiscus sinensis, with particular emphasis on the pattern and sequence of ossification. Ossification starts at late Tokita‐Kuratani stage (TK) 18 with the maxilla, followed by the dentary and prefrontal. The quadrate is the first endoskeletal ossification and appears at TK stage 22. All adult skull elements have started ossification by TK stage 25. Plastral bones are the first postcranial bones to ossify, whereas the nuchal is the first carapacial bone to ossify, appearing as two unstained anlagen. Extensive examination of ossification sequences among autopodial elements reveals much intraspecific variation. Patterns of ossification of cranial dermal elements are more variable than those of endochondral elements, and dermal elements ossify before endochondral ones. Differences in ossification sequences with Apalone spinifera include: in Pelodiscus sinensis the jugal develops relatively early and before the frontal, whereas it appears later in A. spinifera; the frontal appears shortly before the parietal in A. spinifera whereas in P. sinensis the parietal appears several stages before the frontal. Chelydrids exhibit an early development of the postorbital bone and the palatal elements as compared to trionychids. Integration of the onset of ossification data into an analysis of the sequence of skeletal ossification in cryptodirans using the event‐pairing and Parsimov methods reveals heterochronies, some of which reflect the hypothesized phylogeny considered taxa. A functional interpretation of heterochronies is speculative. In the chondrocranium there is no contact between the nasal capsules and planum supraseptale via the sphenethmoid commissurae. The pattern of chondrification of forelimb and hind limb elements is consistent with a primary axis and digital arch. There is no evidence of anterior condensations distal to the radius and tibia. A pattern of quasi‐ simultaneity is seen in the chondrogenesis of the forelimb and the hind limb. J. Morphol. 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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Sang-Oun Jungt Young-Mi Lee Yuri Kartavtsev In-Seok Park Dong Soo Kim Jae-Seong Lee 《DNA sequence》2006,17(6):471-483
We isolated Korean soft-shelled turtle, Pelodiscus sinensis, mitochondrial DNA by long-polymerase chain reaction (long-PCR) with conserved primers and sequenced this mitochondrial genome (mitogenome) with primer walking using flanking sequences. The P. sinensis mitochondrial DNA has 17,042 bp and its structural organization is conserved compared to those of other reptiles and mammals. To unveil the phylogenetic relationship of the turtles, we used the NJ, MP, and ML analysis methods after inferring those sequences from the mitochondrial 16S rRNA gene. We also compared two P. sinensis variants from Korea and China using the mitochondrial genome. In this study, we report the basic characteristics of the P. sinensis mitochondrial genome, including structural organization and base composition of the rRNAs, tRNAs and protein-coding genes, as well as characteristics of tRNAs. These features are applicable for the study of phylogenetic relationships in turtles. 相似文献
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Heiko Stuckas Uwe Fritz 《Journal of Zoological Systematics and Evolutionary Research》2011,49(4):335-339
Recent studies identified several distinct genetic lineages within the softshell turtle genus Pelodiscus that could represent valid species. Traditionally, Pelodiscus was regarded to comprise only a single species (P. sinensis). These softshell turtles are economically the most important chelonians of the world, with hundreds of millions of specimens traded as food every year. Moreover, Pelodiscus is used as a model organism for embryological and physiological studies, making correct species identification of paramount interest for disciplines beyond taxonomy. However, the understanding of the diversity of Pelodiscus was seriously hampered by the unclear taxonomic allocation of the oldest available species name, Trionyx (Aspidonectes) sinensis Wiegmann, 1834 . To clarify its identity, we reconstructed two mitochondrial DNA fragments of 1013 bp (cytb) and 468 bp (ND4) length of one of the two surviving syntypes and designate this specimen as lectotype (ZMB 38, Museum für Naturkunde Berlin). The sequences obtained from the lectotype represent a previously unknown lineage. Using the phylogenetic placement of all lineages and uncorrected p distances of the mitochondrial cytb gene as a yardstick, we suggest that the observed sequence variation is consistent with the existence of at least four distinct species within Pelodiscus. The name P. sinensis should be restricted to turtles harbouring the mitochondrial lineages B, C, D and the lineage of the lectotype. More divergent lineages are to be identified with P. axenaria, P. maackii and P. parviformis, which are recognized as valid species. 相似文献
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维生素C和E混合饲喂对中华鳖幼鳖抗酸应激能力的影响 总被引:8,自引:0,他引:8
来自甲鱼养殖场的60只中华鳖(Pelodiscus sinensis)幼鳖驯养3周后,实验设5组:对照组、处理Ⅰ、Ⅱ、Ⅲ和Ⅳ组。各组设2个平行,依次在饵料中混合添加维生素C(Vc)和E(VE)为0和0、250和50、2500和50、250和250、2500和250mg/kg,喂食4周后,每组取半数幼鳖经酸应激处理24h。取幼鳖血液,用镜检法测定血细胞的吞噬率,透射比浊法测定血清溶菌活力、杀菌活力以及补体C3和C4含量。①经酸应激与未经酸应激处理相比:对照组血细胞吞噬率显著降低,而处理Ⅰ-Ⅳ组无显著变化;对照组和处理Ⅰ组血清溶菌活力和补体C3含量显著下降,而处理Ⅱ-Ⅳ组无显著变化;血清杀菌活力均有显著下降(对照组、处理Ⅰ和Ⅲ组极显著,处理Ⅱ组和Ⅳ组显著);对照组、处理Ⅰ和Ⅲ组血清补体C4显著下降,而处理Ⅱ和Ⅴ组无显著变化。②经酸应激处理,血细胞吞噬率、血清溶菌活力、杀菌活力和补体C3含量,处理Ⅰ~Ⅳ组的均显著高于对照组,处理Ⅳ组显著高于其他4组;血清杀菌活力,处理Ⅱ组又高于处理Ⅰ和Ⅲ组;血清补体C4,对照组显著低于处理Ⅰ-Ⅳ组,而处理Ⅰ-Ⅳ组间无显著相异。Vc和VE混合饲喂对酸应激后中华鳖血细胞吞噬率、血清溶菌活力、杀菌活力和补体C3含量有显著协同促进作用,对血清补体C4的合成无协同作用。说明Vc和VE混合饲喂能显著增强中华鳖抗酸应激能力,缓解或部分缓解酸应激造成的不利影响。 相似文献
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中华鳖线粒体基因组序列分析 总被引:11,自引:0,他引:11
参照近源物种线粒体基因组序列,设计17对特异引物,采用PCR产物直接测序法测得中华鳖线粒体基因组全序列.初步分析其基因组特点和各基因的定位,用pDRAW32软件预测12种限制性酶对其的酶切图谱.结果表明,中华鳖线粒体基因组全长17364bp,核苷酸组成为35.23%A、27.26%T、25.73%C、11.78%G,包括13个蛋白质编码基因、2个rRNA基因、22个tRNA基因和1个非编码控制区.基于线粒体基因组编码的13个蛋白质的氨基酸序列,用NJ法和MP法构建系统进化树,分析6种龟鳖类动物之间的亲缘关系,与传统的系统分类基本一致,初步确定淡水龟科与海龟科的亲缘关系比与龟科的亲缘关系要近. 相似文献
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The molecular evaluation of morphologically based species delimitations of many herpetofauna has improved the understanding of evolutionary processes and the rigor of conservation efforts. Previous evidence for a deep lineage divide between south-eastern + northern subspecies of the softshell turtle Apalone spinifera ( A. s. aspera + A. s. hartwegi + A. s. spinifera ) and western subspecies ( A. s. pallida + A. s. emoryi + A. s. guadalupensis ) was re-examined with a broader sampling using mitochondrial and nuclear markers. The south-eastern + northern clade and the western clade maintained mitochondrial reciprocal monophyly. We molecularly confirmed a geographical boundary between these two clades in Oklahoma, and developed a phylogeographical hypothesis that invokes stream capture. We evaluated whether these mitochondrial lineages represent distinct species by surveying these clades for divergence at the nuclear intron R35 and two nuclear genes, Cmos and recombination activating gene 1 (RAG-1). The nuclear loci showed no phylogenetic resolution and only the nuclear intron exhibited significant nearest neighbour statistics. Taken together, the nuclear data suggest that taxonomic elevation of the two mitochondrial clades would be currently unjustified. 相似文献