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1.
We investigated the lemma micromorphology of 17, primarily Siberian, species of Stipa using scanning electron microscopy (SEM). All the species had variants of the micromorphology considered typical for Stipa but each had a unique combination of characteristics, enabling its identification solely on the basis of its lemma micromorphology. Phenetic analysis revealed little correlation between the observed variation and the current sectional treatment of the species. The data support exclusion of Stipa borysthenica from Stipa pennata. A key to the species is provided.  相似文献   

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A comparison of the morphology and of the venom alkaloids of the Australian Monomorium rothsteini complex was undertaken. These ants were collected in Australia from western New South Wales, northern Queensland, and northern Northern Territory. Additionally, samples from the M. sordidum complex and M. carinatum complex were examined. Thirteen previously described trans‐2,5‐dialkylpyrrolidines were detected in these ants, along with the novel trans‐2‐ethyl‐5‐[(Z)‐tridec‐4‐enyl]pyrrolidine ( 6 ), whose structure was confirmed by synthesis. The extent of variation and the correlation observed in the morphology and venom chemistry in M. rothsteini samples is very strongly indicative of multiple species in this complex. The presence and location of the C?C bond in 6 reinforces the remarkable structural similarity of the 2‐ethylpyrrolidines in these Monomorium species to the 2‐methylpiperidines in the venoms of many Solenopsis species, and may represent convergent evolution of biosynthetic processes in different genera of solenopsidine ants.  相似文献   

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Three species are often accepted in Taeniatherum Nevski. Analysis of morphological characters show that indistinct limits occur between them. All taxa are found to be diploid (2n=14), with the same karyotype, but artificial hybridization shows genetical barrier to exist. For these reasons subspecific level is chosen for the taxa, viz. T. caput-medusae (L.) Nevski ssp. caput-medusae, T. caput-medusae ssp. crinitum (Schreb.) Melderis and T. caput-medusae ssp. asperum (Simk.) Melderis. Map showing known distribution of the subspecies is presented.  相似文献   

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在标本观察和野外调查的基础上,对细莴苣属Stenoseris植物进行了分类学修订,共确认了3种.有3个名称,即Stenoseris leptanthaShih,S.taliensis(Franch.)Shih和S.tenuisShih处理为新异名.此外,重新编制了细莴苣属分种检索表,并较为详细地记录了每种的分布地点.  相似文献   

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Wallemia sebi is a xerophilic food- and air-borne fungus. The name has been used for strains that prevail in cold, temperate and tropical climates. In this study, multi-locus phylogenetic analyses, using the internal transcribed spacer (ITS) regions, DNA replication licensing factor (MCM7), pre-rRNA processing protein (TSR1), RNA polymerase II largest subunit (RPB1), RNA polymerase II second largest subunit (RPB2) and a new marker 3´-phosphoadenosine-5´-phosphatase (HAL2), confirmed the previous hypothesis that W. sebi presents a complex of at least four species. Here, we confirm and apply the phylogenetic analyses based species hypotheses from a companion study to guide phenotypic assessment of W. sebi like strains from a wide range of substrates, climates and continents allowed the recognition of W. sebi sensu stricto and three new species described as W. mellicola, W. Canadensis, and W. tropicalis. The species differ in their conidial size, xerotolerance, halotolerance, chaotolerance, growth temperature regimes, extracellular enzyme activity profiles, and secondary metabolite patterns. A key to all currently accepted Wallemia species is provided that allow their identification on the basis of physiological, micromorphological and culture characters.  相似文献   

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披碱草属(Elymus L.)两个物种之订正   总被引:3,自引:0,他引:3  
披碱草属Elymus L.是小麦族Triticeae Dumort.中最大的属,全世界共有150多个种,广泛分布于 温带地区。我国约有80余种(包括鹅观草属Roegneria C.Koch),是披碱草属的重要分布区和多样性分 化中心。由于披碱草属植物种类繁多、分布广泛、生境多样以及形态变异较为复杂,导致该属在分类上 存在许多问题。同时,由于地域的局限和地区间交流的缺乏,致使同一种披碱草属植物被不同的学者多 次发表及同物异名现象的出现。本文对E.antiquus和E.burchan-buddae这两个曾多次被订名的披碱草 属物种进行了分类订正。  相似文献   

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广东竹亚科新组合及新异名   总被引:2,自引:0,他引:2  
报道了广东竹亚科13新组合,1新名称和3新异名,其中筋竹属3新组合1新名称,牡竹属4新组合,青篱竹属5组合1新异名,箬竹属2新异名及方竹属1新组合.  相似文献   

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赖草属植物的分类现状及主要存在的问题   总被引:1,自引:0,他引:1  
赖草属(Leymus Hochst.)为禾本科(Poaceae)小麦族(Triticeae)中的一个有重要经济价值的属,属内多数种类是优良牧草,有些种类具有耐寒、耐旱、耐碱等特性,是农业良种繁育、畜牧业牧草改良利用的重要基因资源。该属在分类学上是一个疑难属,在属的界限、属下组系的划分,以及类群间演化关系上问题较多。对赖草属分类学问题进行了综述,为赖草属植物资源的开发利用和保护提供资料。  相似文献   

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WEBB, M. E. & ALMEIDA, M. T., 1990. Micromorphology of the leaf epidermis in taxa of the Agropyron-Elymus complex (Poaceae). A comparative analysis by scanning electron microscopy was carried out on both leaf epidermes (adaxial and abaxial) of Elymus pychnanthus (Godr.) Meld, and Agropyron glaucum Roemer & Schultes.
The adaxial epidermes of E.pychnanthus and A. glaucum are similar in the position and the shape of the long cells, silica bodies and costal and papillate prickles. They differ in the higher number of silica cells in E. pychnanthus and in the presence of intercostal hooks in A. glaucum.
The abaxial epidermes of both species are similar in the shape of interstomatal cells, silica bodies and papillate prickles. They differ in the distribution of the stomata and in the contact zones of the long cells. Elymus pychnanthus and A. glaucum differ also in the trichomes situated along the margins of the leaf blade.
These micromorphological differences, especially those of the abaxial epidermis, are useful taxonomic features.  相似文献   

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据有关模式和产地标本的研究,结合野外调查、叶表皮微形态观察结果,对小叶子(Cotoneaster microphyllus Wall.ex Lindl.)进行了分类学修订,将分属3系(Series Procumbens Klotz;Series Alpigeni和Series Marginati  相似文献   

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基于文献考证和标本研究,将宁德冬青(Ilex ningdeensis C. J. Tseng)修订为乌来冬青(I. uraiensis Yamamoto)的异名,并对南平冬青(I. nanpingensis G. S. He)的分类学地位进行讨论。  相似文献   

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小叶栒子的分类学研究   总被引:2,自引:0,他引:2  
据有关模式和产地标本的研究,结合野外调查、叶表皮微形态观察结果,对小叶栒子(Cotoneaster microphyllus Wall.ex Lindl.)进行了分类学修订,将分属 3系(Series Procumbens Klotz; Series Alpigeni和Series Marginati Klotz)的15个名称归并作小叶栒子的同物异名。  相似文献   

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凤丫蕨属(Coniogramme Fée)种间界限模糊,存在过渡类型,是蕨类植物中分类比较困难的类群之一。黑轴凤丫蕨(C.robusta(H.Christ) H.Christ)是凤丫蕨属植物中比较特殊的种类之一。本文在标本考证、野外考察和微形态研究的基础上对该种的分类进行了订正。将假黑轴凤丫蕨(C.pseudorobusta Ching et Shing)和新黑轴凤丫蕨(C.neorobusta Ching et Shing)归并到黑轴凤丫蕨。同时对该种下的两个变种黄轴凤丫蕨(C.robusta var. splendens Ching et Shing)和棕轴凤丫蕨(C.robusta var. rependula Ching et Shing)重新定义模式标本。  相似文献   

18.
The small annual genera Crithopsis, Heteranthelium, Henrardia and Amblyopyrum are revised, maps showing the distribution of the species are presented and the known chromosome numbers are confirmed. The phylogenetic relationships of each genus are discussed. Results of intergeneric hybridizations including the four genera are reported.  相似文献   

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中国大蒜芥属(十字花科)叶表皮微形态学研究   总被引:1,自引:0,他引:1  
利用光学显微镜观察了中国十字花科大蒜芥属9种1变种植物的叶表皮形态。结果表明:中国大蒜芥属植物叶上表皮细胞通常为多边形,垂周壁平直或弓形,少有稍浅波状,叶下表皮细胞为不规则形,垂周壁波状或深波状;气孔器类型均以不等细胞型为主,少有无规则型,偶有平列型。依据叶表皮特征,可将中国大蒜芥属划分为三种类型: (1)叶上表皮无气孔分布或偶见; (2)叶上表皮气孔常明显几个聚成一簇或排成短列,气孔密度小于叶下表皮; (3)叶上表皮气孔比较均匀分布,气孔密度与叶下表皮近相似。  相似文献   

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在电子扫描显微镜下观察了穆属(Eleusine Gaertn.)9种植物颖果的微形态特征.结果表明,穆属颖果有卵形、披针形和矩圆形3种腹面形状,压扁方式有背腹压扁及两侧压扁,腹面形态有平腹面和凹腹面两种,胚比为0.29~0.58,种脐比为0.10~0.24,颖果纹饰有2种,包括疣突状一级纹饰和疣突规则排列构成的复合网状...  相似文献   

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