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1.
目的:进行鄂西南山区重楼属植物资源的调查、引种和资源鉴定,为重楼属植物资源开发提供依据。方法:采取文献调研与野外调查相结合的方法,初步明确该地区的资源现状;引种于适生环境后,参照《重楼属植物》的分类方法,以田间活体标本鉴定为主,以彩色图片鉴定为辅进行品种鉴定。结果:本区重楼属植物分属于中轴亚属和侧膜亚属2个亚属,5个种,7个变种,3个变型,共有15个变异类型,其中白花重楼的2个变型是《重楼属植物》中没有的;以往认为本区有分布的狭叶重楼变种的两个变型中狭叶变型没有收集到。  相似文献   

2.
本文是全文的第二篇。第一篇讨论了三个部分,即属的范畴、亚属分类和脊头金龟亚属。本篇包括第四部分,记述狭肋金龟亚属的17个种,其中有9个新种,3个新记录种,另3个种无标本。  相似文献   

3.
本文研究云南产鳞毛蕨属植物的属下分类并列出所有的种类。该属植物在云南现知至少有88种,属下可划分为3个亚属和12个组。为了使这些类群之间的特征轮廓清晰,本文提供了分亚属及分组的检索表。  相似文献   

4.
硬蜱属Ixodes自Latreille 1795年建立,至今已记录约250种,为硬蜱科中最大的一属。该属下分20亚属,其中以硬蜱亚属Ixodes(s.str.)种类最多,约占全属种类的1/3。硬蜱属的分布以非洲区、古北区和新北区的种类为多,澳大利亚区的种类较少,东洋区的种类亦不多,新热区的记录很少。  相似文献   

5.
多药马兜钤亚属是马兜铃属目前已知3个亚属中最小的一个亚属,约9种,其中8种产于热带 非洲,1种产于热带亚洲(马来西亚)。 本工作从经典分类学角度对该亚属的系统进行了探讨,首次利用花药数目及其排列方式将其划分为三个组,并对其中所含的种类进行了分类学处理,本文承认9种及3个新异名。  相似文献   

6.
高梁属中有重要的粮食作物和优良牧草,也有农业生产上的重要杂草。文章旨在进一步从分子水平阐明高梁属种间的系统进化关系,为有效利用种质资源进行分子育种改良作物品质提供理论依据,并明确检疫性杂草的分类地位。根据二色高粱(Sorghum bicolor)的Adh1全基因序列(GenBank登录号:AF050456)设计引物,扩增并测定黑高梁(S.almum)、假高梁(S.halepense)、丝克高粱(S.silk)和苏丹草(S.sudanense)共计8个植物材料约2000bp的Adh1基因部分序列,结合GenBank中其他24个Sorghum属的同源序列,以Cleistachne sorghoides的对应序列为外群,进行了高梁属的亲缘关系分析,用MP、ML和NJ法分别构建了分子进化树,得到了基本相同的拓扑结构。结果显示:(1)高梁属可明显分为三大支,一支是蒴柄高梁(Chaetosorghum)和异高梁(Heterosorghum)二个亚属,一支是优高梁亚属(Eusorghum),这两个分支包含2n=20、40,染色体较小的种类,另一分支包括拟高梁(Parasorghum)和有柄高梁(Stiposorghum)两个亚属,包含2n=10的种类和它们的多倍体近缘种,染色体相对较大;(2)S.almum的Adh1基因表现出明显的地理分化;(3)Parasorghum亚属的S.purpureosericeum和多色高粱(S.versicolor)、光高粱(S.nitidum)和S.leiocladum聚在一起,而该亚属中的S.matarankense、S.grande、S.timorense却与亚属Stiposorghum的种聚在一起,表现出更近的亲缘关系;(4)S.macrospermum和S.laxiflorum之间具有比其他高梁属种更近的亲缘关系。  相似文献   

7.
曾蕾  闫瑞亚  张梅  许为斌  张林静  于胜祥 《广西植物》2016,36(10):1245-1252
棒凤仙亚属代表着凤仙花属最先分化出的一支,以多年生草本,多于5朵花的总状花序,侧生萼片4枚,3沟花粉,心皮四室且每室具1枚种子,果实棒锤状,种子椭圆形以及三沟花粉其极面观为三角形而区别于其它种类。该亚属主要分布于中国南部,少数种类辐射分布至华中和中南半岛地区。已有报道证实花粉的形态特征对凤仙花属植物的属下分类具有重要意义,但对棒凤仙亚属的种类少有涉及。为了进一步探讨该亚属花粉的形态特征及其分类学价值,该研究应用扫描电镜技术对国产棒凤仙亚属植物的14种以及凤仙花亚属的窄萼凤仙花的花粉进行了观察。结果表明:棒凤仙亚属的花粉以单粒存在,具3条萌发沟,辐射对称,极面观为三角形或三角状圆形,花粉粒外壁具均匀的网状纹饰,网脊平滑或具波状边缘,网眼中具不同密度的颗粒状突起。棒凤仙亚属的花粉形态与水角属的花粉形态相似,表现出了其原始性;其花粉形态特征与花部形态性状等相关性差,对该亚属的组级分类意义较小,但对于该亚属的种间界定具有重要意义;而其花粉的极面观形状、赤道面观形状以及网状纹饰等变异相对稳定,对于界定该亚属具有重要的分类学价值。  相似文献   

8.
根据ITS序列证据重建防己科蝙蝠葛族的系统发育   总被引:10,自引:4,他引:6  
研究了国产防己科蝙蝠葛族tirb.Menispermeae9属20种和外类群青牛胆族trib.Tinosporeae 2属3种植物完整的ITS(包括5.8S rDNA)序列。trib.Menispermeae的ITS长527~601 bp,排序后长667bp。当gap处理为missing时具281个有信息位点。PAUP软件分析结果表明:①trib.Menispermeae是一个单系类群,该分支得到hootstrap l00%的支持;②确定了存疑种Pachygone valida的系统学位置,该种是Coc—culus属的成员;③Sinomenium和Menispermum两属有很近的系统学关系,组成族内稳定的一支,它们的ITS序列同源性极高,ITS1比族内其它属长41~73bp;④Stephania和Cyclea也是系统发育关系很近的两个类群。前者具两个主要分支,其IIS1、ITS2的G+C含量差异较大,在种类组成上,该两大支与传统上Stephania属内处理的2个亚属——千金藤亚属subgen.Stephania和山乌龟亚属subgen.Tuberiphania基本一致;Cyclea属内种间的ITS序列差异小,同源性极高。  相似文献   

9.
叶片恙螨属于恙螨科Trombiculidae的叶片恙螨属Trombiculindus。该属的特征是很明显的,盾片的后侧毛不同于前侧毛,系叶片状或鳞片状。背毛全部叶片状或鳞片状,腹毛全部或部分叶片状或全部毛状。叶片恙螨是从恙螨属Trombicula里的某些种类演化而来的。在演化过程中,某些种类,例如居中恙螨Trombicula intermedia的盾片后侧毛和背毛逐步改变成扁平而窄的柳叶状,两侧锯齿较长。由于这些毛演化程度的不同,该属里的种类分化为二个亚属:(1)羽叶恙螨亚属Plumosicola,(2)叶片恙螨亚属Trombi-culindus。同时也分化而形成了许多种类。到目前为止全世界已知的种类共有11种,主要分布在东南亚地区:6种在印度、1种在马来亚、2种在缅甸(其中1种也在我国)、1种在日本和1种在苏联。  相似文献   

10.
缺齿鼩鼱属Chodsigoa由Kastschenko于1907年作为长尾鼩鼱属Soriculus的一个亚属而建立。Thomas于1908年将其提升为属。该属种类主要分布于中国。其属级分类单元争议很大,一些学者认为是独立属,一些学者认为是长尾鼩鼱属的亚属。属下分类方面,不同学者的分类意见也有所不同。其中,Hutterer(2005)将其作为独立属并包括8个种的观点逐步得到大多数人的认可。造成意见分歧的主要原因是以往的系统学研究主要是以形态学研究为主,分子系统学研究较少。  相似文献   

11.
Liu S  Liu Y  Guo P  Sun Z  Murphy RW  Fan Z  Fu J  Zhang Y 《Zoological science》2012,29(9):610-622
The systematics of Oriental voles remains controversial despite numerous previous studies. In this study, we explore the systematics of all species of Oriental voles, except Eothenomys wardi, using a combination of DNA sequences and morphological data. Our molecular phylogeny, based on two mitochondrial genes (COI and cyt b), resolves the Oriental voles as a monophyletic group with strong support. Four distinct lineages are resolved: Eothenomys, Anteliomys, Caryomys, and the new subgenus Ermites. Based on morphology, we consider Caryomys and Eothenomys to be valid genera. Eothenomys, Anteliomys, and Ermites are subgenera of Eothenomys. The molecular phylogeny resolves subgenera Anteliomys and Ermites as sister taxa. Subgenus Eothenomys is sister to the clade Anteliomys + Ermites. Caryomys is the sister group to genus Eothenomys. Further, the subspecies E. custos hintoni and E. chinensis tarquinius do not cluster with E. custos custos and E. chinensis chinensis, respectively, and the former two taxa are elevated to species level and assigned to the new subgenus Ermites.  相似文献   

12.
绒鼠类系统学研究(啮齿目:仓鼠科:田鼠亚科)   总被引:1,自引:0,他引:1  
在系统综述的基础上对绒鼠属Eothenomys的分类进行了探讨,认为Eothenomys属的典型特征应力;下颌骨臼齿咀嚼面左右两侧的三角形齿环均不呈交错排列,而是两两相对,彼此相融合;二倍染色体数2m=56,全部常染色体均为端部着丝粒(T),东方绒鼠亚属Antheliomys5种中,至少玉龙绒鼠E.proditor不属于此属不能排除恢复Antheliomys属级分类地位的可能性,同意将Caryomys独立为绒Ping属;将Craseomys shanseius Thomas,1908(=E.shanseius)订正为棕背Ping的山西亚种C.r.shanseius。台湾绒鼠Eothenomys kanoi Tokuda,1937的染色体特征与Clethrionomys属相似,不应收入绒鼠属,其分类地位待定。Clethrionomys属和Eothenomys属化石种均最早出现于早更新世,目前还不能断定此二属究竟谁起源于谁,也许它们共同起源于第三者。  相似文献   

13.
绒属Caryomys原为Thomas(1911)命名的Microtus属中的一个新亚属,Hinton(1923)将它升格为独立属,但很快又于1926年否定了此属的存在,从此各国学者或认为它是属Clethrlonomys的同物异名,或认为它是绒鼠属Eothenomys的亚属,近70年间再无人承认此属名。本文通过对Campmys所包含的inez和eva两种的形态学及染色体核型进行研究,并与绒鼠属Eothenomys和属Clethrionomys代表种类的相关特征进行了比较分析,结果表明,inez和eva除在形态上与绒鼠属及属种类有一些明显差异外,在染色体核型上也有显著不同,主要表现在:inez及eva的染色体数目2n=54,且在常染色体中,其最大的一对染色体均为亚端部着丝粒染色体;而绒鼠属和属的染色体数目则为2n=56,且在常染色体中无此对端部着丝粒染色体。为此,作者认为应恢复Caryomxs属的分类地位。  相似文献   

14.
Oriental voles of the genus Eothenomys are predominantly distributed along the Southeastern shoulder of the Qinghai-Tibetan Plateau. Based on phylogenetic analyses of the mitochondrial cytochrome b gene (1143 bp) obtained from 23 specimens (eight species) of Oriental voles collected from this area, together with nucleotide sequences from six specimens (two species) of Japanese red-backed voles (Eothenomys andersoni and Eothenomys smithii) and five species of the closely related genus Clethrionomys, we revised the systematic status of Eothenomys. We also tested if vicariance could explain the observed high species diversity in this area by correlating estimated divergence times to species distribution patterns and corresponding paleo-geographic events. Our results suggest that: (1) the eight species of Oriental voles form a monophyletic group with two distinct clades, and that these two clades should be considered as valid subgenera--Eothenomys and Anteliomys; (2) Eothenomys eleusis and Eothenomys miletus are not independent species; (3) Japanese red-backed voles are more closely related to the genus Clethrionomys than to continental Asian Eothenomys taxa; and (4) the genus Clethrionomys, as presently defined, is paraphyletic. In addition, the process of speciation of Oriental voles appears to be related to the Trans-Himalayan formation via three recent uplift events of the Qinghai-Tibetan Plateau within the last 3.6 million years, as well as to the effects of the mid-Quaternary ice age.  相似文献   

15.
中国茶藨子属的研究   总被引:11,自引:0,他引:11  
通过对国产茶藨子属的形态、分类和地理分布的研究,笔者支持把该属置于虎耳草科的观点,不赞成把它分离作为独立的科。另外,认为Rehder系统中所划分的4个亚属较合理,故予以采纳,但笔者对其中的亚属、组和系的划分、各分类类目的内容、系统排列的顺序等诸方面都作了较大修订。从系统发育的观点出发,对亚属的排列次序则和Rehder系统有很大不同,而对组和系的范围及其系统位置也作了较大改动。中国茶藨子属植物初步确定为59种30变种,隶属于4亚属10组15系(包括5新系)。依据对茶藨子属分布区的分析,首次提出了东亚区是茶藨子属植物的现代分布中心,在东亚区中,中国-喜马拉雅森林植物亚区中的横断山脉地区和中国-日本森林植物亚区的西部是茶藨子属发生和发展的关键地区。  相似文献   

16.
The genus Uroleucon, and the related genus Macrosiphoniella, represent a large Tertiary radiation of aphids, with a total of about 300 species distributed throughout the world, primarily on host plant species in the family Asteraceae. A molecular phylogenetic study was conducted to identify major clades within Uroleucon and to address the cladistic validity of current subgeneric categories, the evolution of host plant associations, the age of origin, and intercontinental movements in this genus. The seventeen study species included members of the three major subgenera of Uroleucon, species from Europe and North America, one member of Macrosiphoniella, and two outgroups. Data consisted of DNA sequences for three mitochondrial regions and the nuclear gene EF1alpha, for a total of 4287 sites. Nodes supported strongly in both parsimony and maximum likelihood analyses suggest that: (1) Nearctic Uromelan are a monophyletic group branching near the base of the genus and not related to European Uromelan, (2) the New World subgenus Lambersius is possibly monophyletic but is not a tightly related group and is not closely related to other North American species, and (3) Nearctic members of subgenus Uroleucon are a closely related monophyletic group not allied with Nearctic Uromelan or Lambersius. Instead they represent a separate colonization by an Old World ancestor, as they are nested within a strongly supported clade containing European members of both subgenera Uroleucon and Uromelan. Neither of these subgenera is monophyletic. Molecular clock calculations, based on calibrations of mitochondrial divergences from other insects, suggest that Uroleucon + Macrosiphoniella is a relatively recent radiation, probably no more than 5–10 million years old. Although largely confined to Asteraceae, this clade did not radiate in parallel with its host plants. Rather, lateral movement between lineages of Asteraceae must have occurred repeatedly.  相似文献   

17.
森林田鼠族(Myodini)是䶄亚科(Arvicolinae)的重要类群,广泛分布于整个全北区及东洋区部分区域,该族目前存在的分类学问题是缺乏化石标本、短时间的物种分化、有限分子样本和部分类群采样困难等综合因素影响的结果。近年中国森林田鼠族的系统分类研究成果主要有:(1)绒鼠属(Eothenomys)的采样和系统发育研究基本涵盖了全部类群,发现1新亚属和4新种,分别为川西绒鼠亚属(Ermites)和石棉绒鼠(Eothenomys shimianensis)、金阳绒鼠(E.jinyangensis)、美姑绒鼠(E.meiguensis)、螺髻山绒鼠(E.luojishanensis),原来被普遍接受的黑腹绒鼠福建亚种(E.melanogaster colurnus)、中华绒鼠康定亚种(E.chinensis tarquinius)、西南绒鼠康定亚种(E.custos hintoni)被证实为3个独立有效种,滇绒鼠(E.eleusis)、丽江绒鼠(E.fidelis)的种级分类地位进一步得到确认;大绒鼠贡山亚种(E.miletus confinii)和黑腹绒鼠滇西亚种(E.melanogaster libonotus)实为克钦绒鼠(E.cachinus)的同物异名。(2)基于形态和分子系统发育的研究支持恢复东亚䶄属(Craseomys)的属级分类地位,同时解决了䶄属(Myodes)的非单系起源问题;研究进一步证实山西䶄(Craseomys shanseius)应为棕背䶄的山西亚种(Craseomys rufocanus shanseius)。(3)高山䶄属(Alticola)的平颅高山䶄亚属(Platycranius)分类地位受到分子系统发育研究结果质疑,该亚属的唯一物种平颅高山䶄(Alticola strelzowi)与高山䶄属指名亚属物种聚在同一枝;库蒙高山䶄(A.stracheyi)实为斯氏高山䶄(A.stoliczkanus)的同物异名。基于近年系统分类研究结果,目前中国森林田鼠族分布有5属共30种。  相似文献   

18.
We inferred the phylogeny of 21 species and subspecies of ticks from the subfamilies Rhipicephalinae and Hyalomminae using cytochrome c oxidase subunit I (COI) and 12S rRNA mitochondrial gene sequences. Two members of the subfamily Haemaphysalinae were used for outgroup reference. The largest rhipicephaline genus, Rhipicephalus, was represented by ticks from six of the species groups, the second largest genus, Dermacentor, by species from two of three of its subgenera, and the genus Boophilus by 3 of its 5 species. We analyzed the 12S and COI sequences separately and together; statistically significant incongruence between the 12S rDNA and the COI sequences was not detected in the combined dataset using the incongruence length difference test. The combined dataset provided greater phylogenetic resolution than the individual datasets, and although the 12S rDNA data had only 25% of the parsimony-informative characters, it provided half of the total partitioned Bremer support for the combined dataset. We present the first hypothesis of phylogenetic relationships among some species groups of Rhipicephalus but our most controversial result was that the genus Rhipicephalus is apparently paraphyletic, unless species of Boophilus are included in it. The species of Rhipicephalus most closely related to Boophilus spp. were from the R. pravus and R. evertsi species groups, which may implicate an African origin for this important group of ticks.  相似文献   

19.
With about 350 species, Paspalum is one of the richest genera within the Poaceae. Its species inhabit ecologically diverse areas along the Americas and they are largely responsible for the biodiversity of grassland ecosystems in South America. Despite its size and relevance, no phylogeny of the genus as a whole is currently available and infrageneric relationships remain uncertain. Many Paspalum species consist of sexual-diploid and apomictic-polyploid cytotypes, and several have arisen through hybridization. In this paper we explore the phylogenetic structure of Paspalum using sequence data of four non-coding cpDNA fragments from a wide array of species which were combined with morphological data for a subset of diploid taxa. Our results confirmed the general monophyly of Paspalum if P. inaequivalve is excluded and the small genus Thrasyopsis is included. Only one of the four currently recognized subgenera was monophyletic but nested within the remainder of the genus. Some informal morphological groups were found to be polyphyletic. The placement of known allopolyploid groups is generally congruent with previously stated hypotheses although some species with shared genomic formulae formed paraphyletic arrangements. Other species formed a basal grade including mostly umbrophilous or hygrophilous species. It is hypothesized that the genus may have diversified as a consequence of the expansion of C4 grass-dominated grasslands in South America.  相似文献   

20.
Synopsis Current information on systematics and morphology of larvae and juveniles ofSebastes is reviewed, as are intrageneric relationships among the many species of the genus. Although some subgenera may remain after a cladistic analysis of the genus, others are probably artificial groupings of species that have convergent morphologies because of similar ecology. The relationships ofSebastes to other scorpaeniform fishes as well as the relationships of scorpaeniforms to other fishes are not resolved. Of the 102 species ofSebastes worldwide, 69 species have been illustrated as preflexion larvae, 35 as postflexion larvae and 65 as pelagic juveniles. Morphological characters of each of these stages were used to compare species, group them by similar appearances and then compare these groupings with existing subgenera. Some pigment patterns of preflexion larvae were rather consistent among species within certain subgenera but quite variable among species in other subgenera. Postflexion larvae fell into 11 groups based on pigment, head spines and body shape. These groups were not closely aligned with the subgeneric assignments of the component species. On the basis of pigment patterns of pelagic juveniles, six groups were evident, but the specific composition of these groups bore little resemblance to either the larval or subgeneric groups.  相似文献   

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