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1.
- 1 The stripe‐backed weasel Mustela strigidorsa is one of the rarest and least‐known mustelids in the world. Its phylogenetic relationships with other Mustela species remain controversial, though several unique morphological features distinguish it from congeners.
- 2 It probably lives mainly in evergreen forests in hills and mountains, but has also been recorded from plains forest, dense scrub, secondary forest, grassland and farmland. Known sites range in altitude from 90 m to 2500 m. Data are insufficient to distinguish between habitat and altitudes which support populations, and those where only dispersing animals may occur.
- 3 It has been confirmed from many localities in north‐east India, north and central Myanmar, south China, north Thailand, north and central Laos, and north and central Vietnam. Given the limited survey effort, the number of recent records shows that the species is not as rare as hitherto believed. Neither specific nor urgent conservation needs are apparent.
2.
ROYA KARAMIAN MASSOUD RANJBAR 《Botanical journal of the Linnean Society. Linnean Society of London》2005,147(3):363-368
Astragalus rahiminejadii , a new species endemic to Iran, is described and illustrated. This species, which belongs to section Astragalus , is confined to the western part of Iran (Prov. Kermanshah) and is known only from a single population. Seed testa morphology as viewed under the scanning electron microscope is discussed and photomicrographs are provided. In addition, the geographical distribution and ecology of the species belonging to this section are discussed. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 363–368. 相似文献
3.
L. A. Kutikova 《Hydrobiologia》1980,73(1-3):215-220
An attempt is undertaken to determine criteria and limits of taxonomic rank in the genus Notholca proceeding from the standpoint of level-values of the characters evolution. Level-values of characters were established using Vavilov's principle of homologic series of hereditary variability. As a result of taxonomic revision such terms as group of species, species and subspecies are recommended. Analysis of the scheme of relations between representatives of the genus and data on their ranges gives a clue to relations between phylogeny and geographic distribution of the group over the vast territory of the Asian continent which may have been its centre of speciation. 相似文献
4.
LUCIA HELENA SOARES-SILVA VIDAL DE FREITAS MANSANO 《Botanical journal of the Linnean Society. Linnean Society of London》2004,146(1):103-106
A new species Exostyles godoyensis Soares-Silva & Mansano (Leguminosae, Papilionoideae, Swartzieae), endemic to Paraná state in southern Brazil, is described and illustrated. The new species is distinct from all the other species of Exostyles in having a leaf with up to five leaflets, while the other species have at least seven leaflets per leaf. The new species is distinct from Exostyles amazonica Yakovlev in its longer stamen filaments and ovary stipe and from E. glabra Vogel and E. venusta Schott by its shorter anthers. In addition to these morphological characters E. godoyensis has a disjunct geographical distribution. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 103–106. 相似文献
5.
卷柏科仅含一属,全球分布,具有宽幅生态适应性,属于维管植物基部类群石松类植物,现生约700种。卷柏科起源于泥盆纪,化石记录遍布自石炭纪至今的各地质时期。目前,现代卷柏属亚属的分类方案基本稳定,但对于化石卷柏的亚属分类、以及地质历史时期的时空分布问题还缺乏相关研究。本文全面总结了卷柏科化石记录的时代和地理分布,并结合分子系统学探讨其地理分布格局的演化,为该科植物的分类与进化研究提供参考。根据现有研究基础,结合最新的卷柏科系统分类研究成果和化石记录,本文对该类群化石的系统分类进行归纳和厘定,并对化石类群的卷柏亚属Selaginella、Hexaphyllum亚属及rhizophoric clade物种的分化和地理分布格局的形成进行了讨论。本文认为,卷柏科起源于古生代的欧美植物区,不晚于二叠纪,其后伴随着泛大陆解体扩散至华夏植物区及冈瓦纳植物区。化石亚属Hexaphyllum是rhizophoric clade的基部类群,在石炭纪末灭绝。化石证据表明,从古生代末期起,rhizophoric clade已成为卷柏科的优势类群,并在中生代形成了全球分布的格局。 相似文献
6.
Friedrich Kiefer 《Hydrobiologia》1982,93(3):223-253
Revision of the Asiatic representatives of the genus Tropodiaptomus. Of the 20 names hitherto given for species or varieties, one is a nomen nudum, 9 forms are characterized insufficiently and, hence, their taxonomical position is still uncertain, 10 species are redescribed and illustrated, and 2 taxa have proved to be new to science. 相似文献
7.
河北省苔类植物新纪录属的研究—I.耳叶苔属（Frullania Raddi） 总被引：1，自引：0，他引：1
在研究标本和文献的基础上,对河北省苔类植物新纪录属-耳叶苔属Frullania Raddi进行了首次报道,其中包括达乌里耳叶苔F.davurica、达乌里耳叶苔凹叶变种F.davuricavar.concava、石生耳叶苔F.inflata、盔瓣耳叶苔F.muscicola、陕西耳叶苔F.schensiana、塔拉大克耳叶苔F.taradakensis、远东耳叶苔F.fauriana和筒瓣耳叶苔F.diversitexta等7种1变种。本文对它们的生境和地理分布作了初步讨论,并编制了河北省耳叶苔属植物的分种检索表。 相似文献
8.
控制水稻胚乳淀粉合成代谢若干关键酶基因对花后高温的响应表达 总被引：1，自引：0，他引：1
以稻米品质温度敏感型的早籼稻品种嘉早935为材料,利用人工气候箱控温试验和实时荧光定量PCR技术,探讨了不同灌浆温度(日均温分别为22和32 ℃)处理下胚乳淀粉分支酶(SBE)、淀粉去分支酶(DBE)和淀粉合酶(SS)的10个同工型基因(sbe1、sbe3、sbe4、pul、isa1、isa2、isa3、Wx、sss1和sss2a)的相对表达量差异及动态变化特征.结果表明: 淀粉合成相关功能基因对水稻灌浆期高温胁迫的响应表达方式存在明显差异,而且因同工型的类型而不同.在高温处理下,sbe1和sbe3的相对表达量显著下降,二者属于SBE类基因中对高温胁迫较敏感的主要同工型;DBE基因中,pul属于高表达的同工型,而且其对高温胁迫响应比isa1、isa2和isa3敏感;在Wx、sss1和sss2a中,sss2a的相对表达量显著低于sss1和Wx, 但sss2a和sss1对高温胁迫响应比Wx敏感,因此二者可能也是高温胁迫对胚乳淀粉结构进行调控的重要位点,尤其在水稻灌浆的中后期发挥重要作用. 相似文献
9.
在研究标本和文献的基础上,对河北省苔类植物新纪录属--耳叶苔属Frullania Raddi进行了首次报道,其中包括达乌里耳叶苔F. davurica、达乌里耳叶苔凹叶变种F. davurica var. concava、石生耳叶苔F. inflata、盔瓣耳叶苔F. muscicola、陕西耳叶苔F. schensiana、塔拉大克耳叶苔F. taradakensis、远东耳叶苔F. fauriana和筒瓣耳叶苔F. diversitexta等7种1变种。本文对它们的生境和地理分布作了初步讨论,并编制了河北省耳叶苔属植物的分种检索表。 相似文献
10.
11.
滇金丝猴（Rhinopithecusbieti）现状及其保护对策研究 总被引：3，自引：0，他引：3
滇金丝猴（Ｒｈｉｎｏｐｉｔｈｅｃｕｓｂｉｅｔｉ）是我国特有的珍稀濒危动物,生活在海拔３８００～４３００ｍ的原始冷杉林中,但有时也会在４３００～４７００ｍ的低矮灌丛、草甸和流石滩上活动达数小时之久,甚至能跨越近千米的无林高海拔地带,因而它们是海拔分布最高的非人灵长类。松萝是它们的主要食物,取食松萝的时间占总取食时间的９１％。猴群活动范围可达近百平方公里。笔者在历时８年的野外考察中,已查明这一物种的全部现存自然种群只有１３个,分布在云南的德钦、兰坪、潍西、丽江和西藏的芒康这五县境内,其现存种群数量为１０００～１５００只;所有现存自然种群几乎均处在相互隔离的状态,群间已不可能进行基因交流,充分表明它们已到达灭绝边缘。然而其栖息地内的商业伐木规模仍在继续扩大,周围的人口压力正在不断增加,各猴群均面临不同程度的偷猎压力。这一现状委实令人担忧。如何拯救这一“国宝”应引起我国保护学家和各级政府有关职能部门的重视 相似文献
12.
菌食性管蓟马是土壤动物的重要组分, 它们在生物多样性保护与利用、植物保护、动物地理等领域具有重要的研究价值, 但在我国其分类和物种多样性研究仍有较大不足, 大尺度分布格局形成原因也不清楚。本文基于对我国大部分地区广泛的野外采集调查和国内外多家研究机构馆藏标本的检视, 整理了我国菌食性管蓟马物种名录和地理分布信息, 总结了我国菌食性管蓟马的分类研究现状与简史, 分析了菌食性管蓟马物种多样性的分布格局并探讨了该格局形成原因。目前我国记录菌食性管蓟马237种, 其中管蓟马亚科39属156种, 灵管蓟马亚科22属81种; 竹管蓟马属(Bamboosiella)、剪管蓟马属(Psalidothrips)、网管蓟马属(Apelaunothrips)和全管蓟马属(Holothrips)是物种较多的属, 包含物种数均超过10种; 中国特有73种; 广东、台湾、海南和云南是物种最丰富的省份, 均超过60种, 这些省份都具热带和亚热带气候特征, 适合其生存; 相对多度分析结果表明在热带和亚热带地区森林凋落物层菌食性管蓟马是土壤动物的常见类群; 气温、降水量、食物等是限制其分布的主要因素。本结果丰富了土壤生物多样性的研究内容, 为菌食性管蓟马多样性大尺度空间格局研究提供了数据支持。 相似文献
13.
Telmatochromis brachygnathus sp.n. is described from the southern and central parts of Lake Tanganyika. It can be distinguished from the similar T. temporalis mainly by its smaller mouth. Morphological distinct populations were found in both species. 相似文献
14.
Julie Watrin Anne-Marie Lézine Konrad Gajewski Annie Vincens 《Journal of Biogeography》2007,34(3):489-499
Aim To demonstrate that incorporating the bioclimatic range of possible contributor plants leads to improved accuracy in interpreting the palaeoclimatic record of taxonomically complex pollen types.
Location North Tropical Africa.
Methods The geographical ranges of selected African plants were extracted from the literature and geo-referenced. These plant ranges were compared with the pollen percentages obtained from a network of surface sediments. Climate-response surfaces were graphed for each pollen taxon and each corresponding plant species.
Results Several patterns can be identified, including taxa for which the pollen and plant distributions coincide, and others where the range limits diverge. Some pollen types display a reduced climate range compared with that of the corresponding plant species, due to low pollen production and/or dispersal. For other taxa, corresponding to high pollen producers such as pioneer taxa, pollen types display a larger climatic envelope than that of the corresponding plants. The number of species contained in a pollen taxon is an important factor, as the botanical species included in a taxon may have different geographical and climate distributions.
Main conclusions The comparison between pollen and plant distributions is an essential step towards more precise vegetation and climate reconstructions in Africa, as it identifies taxa that have a high correspondence between pollen and plant distribution patterns. Our method is a useful tool to reassess biome reconstructions in Africa and to characterize accurately the vegetation and climate conditions at a regional scale, from pollen data. 相似文献
Location North Tropical Africa.
Methods The geographical ranges of selected African plants were extracted from the literature and geo-referenced. These plant ranges were compared with the pollen percentages obtained from a network of surface sediments. Climate-response surfaces were graphed for each pollen taxon and each corresponding plant species.
Results Several patterns can be identified, including taxa for which the pollen and plant distributions coincide, and others where the range limits diverge. Some pollen types display a reduced climate range compared with that of the corresponding plant species, due to low pollen production and/or dispersal. For other taxa, corresponding to high pollen producers such as pioneer taxa, pollen types display a larger climatic envelope than that of the corresponding plants. The number of species contained in a pollen taxon is an important factor, as the botanical species included in a taxon may have different geographical and climate distributions.
Main conclusions The comparison between pollen and plant distributions is an essential step towards more precise vegetation and climate reconstructions in Africa, as it identifies taxa that have a high correspondence between pollen and plant distribution patterns. Our method is a useful tool to reassess biome reconstructions in Africa and to characterize accurately the vegetation and climate conditions at a regional scale, from pollen data. 相似文献
15.
There are at least 86 species of troglomorphic fishes belonging to 18 families. Some of those families are characterized by features that can be labeled as preadaptations to the hypogean life; others are not. The level of structural reduction in eye development and pigmentation is highly variable, even within some populations. Reduction in number and complexity of scales does occur but has yet to be fully documented. Reduction in the size and structure of the swim(gas)bladder may be another troglomorphic feature. There is considerable doubt on the taxonomic position of many species of troglomorphic fishes given that a number of them have been described solely on the basis of morphology while genetically they may be very closely correlated to genera different from those they have been assigned to. Geographically speaking there are no evident patterns since many of those species are not found in karstic areas but in phreatic waters. These fishes represent an excellent example of convergent evolution. 相似文献
16.
The eel genus Histiobranchus Gill occurs benthopelagically over the continental rise and abyss of the World Ocean, primarily beneath temperate and subpolar surface waters. Its generic status within the subfamily Synaphobranchinae is confirmed by comparison of the structure and topography of its cephalic sensory system and skeletal features with Synaphobranchus. At least three species of Histiobranchus are recognized: H. bathybius (panoceanic), H. bruuni (Tasman Sea and waters south-east of New Zealand) and H. australis (two geographical forms; South Atlantic and south-western Indian Ocean, and South Indo-West Pacific Oceans). Collections totalling 319 specimens of H. bathybius from the eastern North Atlantic (1790–5440 m depth) yielded a size range of 99–1370 mm total length ( L T ), with no apparent sexual dimorphism. Length–frequency distributions indicate a mode of juvenile fish at around 100–200 mm L T and a further two around 600–700 and 1300–1400 mm L T among adults. Generally smaller fish occur in shallower regions, although the size range is broad over the whole depth range. No apparent trend occurs in the size distribution with latitude over the range 17–54) N. Females outnumber males (1 male : 1·7 females) and both sexes are largely distinguishable from 300 mm L T . Ripening eggs occur in females from both adult length modes, with running ripe and spent females of very different size indicating iteroparity. 相似文献
17.
Wild lentils are potential genetic resources for the cultivated lentil, Lens culinaris ssp. culinaris. Their actual value for crop improvement depends on their genetic relationships with the cultigen and their diversity for traits of economic importance. The current view on Lens taxonomy and the latest information on geographic distribution and ecology of the wild taxa are reviewed. The latter is essential for successful collection of wild lentils in their natural habitats. Intraspecific variation is extensively reviewed and evidence for cryptic speciation has been indicated. Crossability potential divides the genus into two groups: L. culinaris — L. odemensis and L. ervoides — L. nigricans. Crosses between members of different group fail because of hybrid embryo abortion. Using embryo culture, viable hybrids can be obtained between L. ervoides and members of the other group. Of the wild lentils, the putative ancestor of the cultigen, L. culinaris ssp. orientalis, is a member of the crop's primary gene pool, whereas L. odemensis and L. ervoides constitute the secondary gene pool. Morphological, physiological, and genetic attributes of ssp. orientalis have been used to assess the process of lentil domestication. It has been pointed out that elimination of seed dormancy was a necessary step for successful lentil cultivation, and that the dormancy-free type probably evolved in wild stands by the aid of selection pressure exerted by man. 相似文献
18.
Henrik Æ. Pedersen Santi Watthana Kanok‐Orn Srimuang 《Botanical journal of the Linnean Society. Linnean Society of London》2013,172(3):358-370
The systematically difficult genus Epipactis (Orchidaceae) is often subdivided into two sections: Epipactis and Arthrochilium. Until now, the latter has attracted much less taxonomic attention than the former, but here we reassess the alleged distinction of two rare and nationally endangered taxa from tropical Asia (E. flava, E. atromarginata), based on morphological examination of live plants in situ in northern Thailand and of herbarium specimens from the entire range of the complex (Thailand, Laos and Vietnam). As the variation in vegetative and floral dimensions, flower colour and labellum morphology broadly overlaps between the two taxa, we merge them under the oldest valid name at species level, E. flava. Geomorphological features of our three study sites in Thailand and high shared occurrence of previously confirmed rheophytes among the accompanying species indicate that E. flava is itself rheophytic (a very rare feature in the Orchidaceae). Possible adaptations of E. flava to its rheophytic lifestyle are discussed. Among these, the formation of pure stands through dense clonal growth involving a creeping rhizome places E. flava as a ‘mat‐rooted rheophytic landplant’ (sensu van Steenis). Combining taxonomic, distributional and ecological data, we discuss the occurrence of this stream‐inhabiting Epipactis in a conservation context. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 358–370. 相似文献
19.
南海东沙岛及太平岛鱼类种类组成和动物地理学特点 总被引：1，自引：0，他引：1
就笔者等在南海之东沙岛及太平岛两处海域所调查记录到的珊瑚礁鱼类,连同自1975年以来之文献与数据库的记录作综合整理.结果表明,东沙岛有73科652种,太平岛有56科466种,两岛合计共有76科759种.太平岛所记录的总鱼种数较东沙岛为少,主要原因纯系因太平岛之礁域面积较小,且调查次数甚少之故.根据各鱼种地理分布范围之分析,发现在此二岛所记录到的鱼种几乎全部都是印度-太平洋、印度-西太平洋及西太平洋等广泛分布的鱼种,目前只有黄头刻齿雀鲷(Chrysiptera chrysocephala)1种是只在南海发现之鱼种.由此可推测南海的鱼类相应与周边海域或珊瑚三角的鱼类相充分交流,并未有明显隔离或种化的现象.东沙岛及太平岛鱼类相之Sφrensen相似性系数值虽已达85.69％,但其中仍有240种是只分布在东沙岛及台湾(165种),或太平岛及台湾(75种),而未在另一岛屿发现之鱼种,且其中只在太平岛及东沙岛发现的21种及20种鱼中,大多为稀有种,非常不容易被调查到.故推测目前在此二岛所作的调查频度相当不足,如果调查能更密集更长期,则两岛的鱼相会更相似. 相似文献