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1.
This paper deals with some species of Lunathyrium Koidz. in N. E. Asia; including the eastern mountainous district of N. E. China;  Far East Region of U. S. S. R.; Korea and Japan.  相似文献   

2.
eterachopsis was proposed by the senior author as an independent genus of the family Aspleniaceae in 1940 with 2 species.  Since then much study on its morpho- logy,  anatomy,  gametophyte and palynology has been carried out by Nayar,  Bir,  Chan- dra & Nayar and Chang et al.,  and they are of the opinion that the genus like Ceterach, is a comparatively primitive element in the family Aspleniaceae.  The queer zigzag pa- tern of cutting of lanceolate fronds appears extraordinary in the family Aspleniaceae, and also suggests its antiquity in evolution. So far only 3 species  (C.  dalhousiae,  C. paucivenosa and C. magnifica) are recognized,  the former from W. Himalayas,  also known from Africa,  while the latter two from W. S. China (Yunnan).  However,  in the past forty years the Chinese botanists have discovered 2 more species as new in N. W. Yunnan,  thus bringing the total known species of the genus up to 5.  The present paper is a brief summary on the genus Ceterachopsis,  which will be published in detail in the Flora Sinica vol. 4.       Pteridologists are also divided in their views regarding the generic status of Cete- rachopsis with 5 well-defined species in Yunnan and the East Himalayas.  We prefer to mintain it as a genus separate from Asplenium on account of its distinct morpholo- gical features.  It is to be hoped that more species may come to light in the mountainsin N. W. Yunnan through further exploration now under way.  相似文献   

3.
 One new species of the genus Mecodium, M. paramnioides H. G.Zhou et W. M. Chu, is described from Guangxi, China.  相似文献   

4.
 Nine new species and twelve new varieties of Athyriaceae from the Hengduan Mountains, China, are described.  相似文献   

5.
发现滇桂三相蕨Ataxipteris dianguiensis W. M. Chu & H. G. Zhou和多形叉蕨Tecataria polymorpha (Wall. ex Hook.) Copel.为海南新分布, 并为滇桂三相蕨指定了后选模式,讨论了燕尾叉蕨T. simonsii (Baker) Ching和中型叉蕨T. media Ching的异同,澄清了三叉蕨T. subtriphylla (Hook. & Arn.) Copel.和多形叉蕨的形态变异,把云南产狭基叉蕨T. polymorpha var. subcuneata Ching & Chu H. Wang处理为多形叉蕨的异名。至此,海南产叉蕨科植物为8属20种。  相似文献   

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9.
Polystichum adungense ching et Fraser-Jenkins is described as new from N. Bur- ma and S. W. China  相似文献   

10.
山东鳞毛蕨属一新种   总被引:1,自引:0,他引:1  
  相似文献   

11.
 讨论了长距美冠兰Eulophia dabia及其近缘种的分类与命名问题。Eulophia dabia的基名Bletia Dabia乃是D.Don(1825)合法发表的最早名称,尽管D.Don的“Dabia”很可能是在袭用Hamilton的“dubia”时拼写上的笔误。为了避免进一步的混乱,明智的做法是接受Don拼写的加词,而避开其语源上的麻烦。在分类方面,可以接受Hooker(1890)将Eulophia campestris Lindl.、E.rupestris Lindl、E.ramentacea Lindl.与Bletia Dabia D.Don:予以合并的观点,以及Deva&Naithani(1986)将Eulophia hormusjii Duthie并入 E.dabia的做法。此外,本文还将Eulophia turkestanica (Litw.)Schltr.和E. faberi Rolfe也归并入 Eulophiadabia。因此,长距美冠兰是一个广布种,白土库曼东部经塔吉克、阿富汗东部、巴基斯坦、克什米尔地区,印度北部、尼泊尔、锡金、不丹、缅甸北部直到中国(云南西南部、四川中部到东部、贵州西南部和江苏),海拔在400~2300 m之间。  相似文献   

12.
The genus Cephalotaxus contains a small number of species. It is adequately appreciated as a newly discovered cancerresistant medicament for the alkaloids obtai- ned from its branches leaves and barks are of curative effect.      This paper deals with the classificatory revision based on the morphological featu- res,  with the reference to the anatomical characters of leaves,  types of alkaloids and pollen morphology observed.  Two new combinations are proposed,  and 4 species and varieties are reduced in the paper. The genus Cephalotaxus is thus suggested to consist of 2 sections and 9 species.  The trees occur in East Asia and the north of Indo-China, with 88% found in China where is the distribution centre and refuge of the genus. The genus in discussion is of unique morphological features which are distinctly dif- ferent from these of Amentotaxus,  Cephalotaxaceae,  containing a single genus of Ce- phalotaxus,  is closely related to Taxaceae,  and therefore the Cephalotaxaceae is best placed in the Taxinieae of Coniferales.  相似文献   

13.
 The fern genus Diplaziopsis C. Chr. of Index Filicum has long been considered as a monotypic one, with the sole species, D. javanica (B1.) C. Chr. from tropical Asia.  In 1906, H. Christ described a second species, Allantodia cavaleriana Christ (=D. cavale- riana C. Chr.) from Kweichow, West China, but this was since not fully recognized by fern students in general, being often considered as a variety of the first species.  This is certainly a mistake, as is shown by ample herbarium specimens today.  In the recent work on the genus, the writer has found among the herbarium material two additional new species from China, thus bringing the genus up to four species in Asia, mainly from China, where, as it is, the genus has its center of development from the long past.      Phylogenetically, Diplaziopsis C. Chr. represents one of the offshoots from the great stock of diplazioid ferns, of which the genus Diplazium Sw. constitutes the main body of the group and from which our genus differs chiefly in its leaves of a thin texture with reticulated venation, but not so much in its type of indusium as it has generally been emphasized by most botanists in the past, for, as it is, the type of indusium in Di- plaziopsis also prevails in many species of Diplazium, for which C. B. Clarke (Trans. Linn. Soc. ser. 2, Bot. I:495, 1880) created, but really superfluously, a subgenus Pseudal- lantodia, about which the writer will dwell in another paper in the near future.  Suffice it to say here that the indusium in Diplaziopsis as revealed by the species treated here is, indeed, typical of diplazioid ferns, only often, as it happens, with  its  adaxial  edge pressed so tight under the expanding sorus that it is unable to open freely along its upper free edge and, as a result, its thin vaulted back bursts open from the pressure of the ex- panding sorus underneath.      As a result of the present study, following four species of the genus have been re- cognized.      Diplaziopsis javanica (B1.) C. Chr. Ind. Fil. (1905) 227.      Wide spread in tropical Asia, northwardly to Bakbo and the southern part of Yun- nan, China.      D. cavaleriana (Christ) C. Chr. Ind. Fil. Suppl. I (1913) 25.      Ranges from West China through northern part of Fukien of East China to Japan.      D. intermedia Ching, sp. nov.      Endemic in West China:  Mt. Omei, Szechuan, and Kweichow.      D. hainanensis Ching, sp. nov.      In conclusion, it may be pointed out that with the modern plant taxonomy pursued in a more efficient manner than in the past, and especially by the introduction of the cytotaxonomic methods, the so-called “monotypic genera”, as conceived by the orthodox systematists, will continue to prove, to a great extent, to be lack of  enough  scientific ground.  The fact that the “monotypic genus” of Diplaziopsis C. Chr. is now found to be a genus of four well-defined species is once again an instance to illustrate the pointat issue.  相似文献   

14.
报道了发现于新疆布尔津的一个中国新记录种——卵形薹草Carex leporina L.,提供了其形态描述和线描图。该种因具有雌雄顺序的小穗和鳞片状的苞片而与卵果薹草C. maackii Maxim.近缘,但花序较短、小穗较少而与后者不同。这两种植物隶属于薹草属二柱薹草亚属卵形薹草组subgen. Vignea sect. Ovales。  相似文献   

15.
 橐吾属Ligularia Cass.是菊科千里光族款冬亚族的一个大属。在款冬亚族中本属与大吾风草属 Farfugium Lindl.亲缘关系最近,但进化程度较高。本属包括6组,11系129种。所有种类均分布在 亚洲,仅2种扩散至欧洲。在东亚地区有119种,占该属总种数的96%。高度集中在横断山区的有4组、 6系67种,其中61种为特有种,占该属总组数的66%,总系数的54.5%,总种数的52%。这个事实 表明了横断山区是该属的多度中心和多样化中心。通过性状分析,伞房组伞房系Sect.Corymbosae, Ser.Calthifoliae叶肾形,具掌状叶脉,头状花序大而少,排列呈伞房状,总苞半球形,被认为是该属的 原始类群。原始种齿叶橐吾L. dentata和鹿蹄橐吾L.hodgsonii的分布区从我国四川东部经过湖北、湖 南、安徽、福建等省至日本。这个分布格局与近缘属大吴风草属Farfugium一致。     根据共同起源原理,这两个属的祖先极有可能就发生在这一地区。因此我们推测东亚地区从中国四 川东部至日本这一地区是本属的发源地,然而根据地质历史和现代分布,作者认为中国中部(包括四川 东部)是本属的初始起源地。该属起源后,基本上沿亚洲南缘的山地扩散,少数种类向东北至亚洲东北部。本属起源时间至少不晚于中白垩纪。  相似文献   

16.
兰科的兜被兰属约有12种,主要分布于亚洲的温带至亚热带山地,我国的四川和云南是其现代分布中心和分化中心。本文通过植物地理学、孢粉学和解剖学的研究,对该属进行分类学订正,确认中国产有12种,其中9种为我国特有,包括4个新种和1个新组合种。  相似文献   

17.
The Astilbe Buch.-Ham.  ex D. Don was founded in  1912.  There are now 18 species throughout the world. USSR, Thailand, Indonesia, Bhutan, Nepal d Kashan- mir each has only 1 species; Korea, Philippines and USA each has 2; India 3; Japan 6; and China 7 (including 3 endemics and 1 new variety). And northeast China, north China and northwest China each has 2;  central China and southwest China  each 4; eastern  China 5. Thus the distribution centre of this genus seems  to be in the region  covering Japan and eastern, central, and southwest China.       This genus is divided into two sections: Sect. Simplicifoliae Engl.  and Sect. Astilbe. Sect. Simplicifoliae may be considered as the primitive one because it has 5 ordinary petals. This section consists of about 10 species: 5 in  China (east China 4; southwest China 3; ce- ntral China, north China and northeast China each 2; Northwest China 1), 5 in Japan, 2 in Korea, 1 in Philippines and India each. According to the distribution of this section, the author suggests that the centre of origin of this genus be in the  forested  parts  from Japonthrough east China to southwest China.  相似文献   

18.
 This paper reports chromosome  number  and karyotype  analysis  of Cycas panzhihuaensis endemic to China.  The material was collected from Dukou, Si- chuan. It is a diploid species, with 2n=22=2m+4sm+4st+l2t. The karyotype of Cycas panzhihuaensis is different from that of the other species of the genus Cycas, which was known to be 2n=4m+8st+10t.  The former is a new karyotype in the genus.  The authors briefly discuss karyotype evolution of the genus Cycas in this papar.  相似文献   

19.
淫羊藿属的种数与60年前大不相同,现在已知约有50种。该属种类间断地分布于日本至北非 的阿尔及利亚之间的广大地区,这一分布格局表明了该属的古老性质。它们在欧亚大陆的分布极不均 匀,约有80%的种类产于中国中部至东南部,而且根据花瓣的演化分析结果表明,只有中国的淫羊藿属 植物具有连续不断的演化过程。由此可见,中国中部至东南部成为北半球淫羊藿属植物的汇集中心是 有充分根据的。淫羊藿属种类基本上是林地草本植物,常生于水青冈林下,为林下草本层的优势种,而 且该属的分布格局与第三纪植物属——水青冈属在欧亚大陆的分布格局极为相似,说明淫羊藿属植物 在早第三纪时期已广泛分布于北半球。中新世时期由于中亚地区气候变干,加之印度板块向欧亚大陆 俯冲并引起喜马拉雅山脉隆起,致使中亚地区进一步干旱,水青冈属和淫羊霍属植物随之消失,进而导致其东亚—地中海、西亚间断分布格局的形成。  相似文献   

20.
2022年,联合国政府间气候变化专门委员会(IPCC)的第六次评估报告《气候变化2022:影响、适应和脆弱性》和中国气象局《中国气候变化蓝皮书(2022)》对外发布。文章简要介绍了其中有关气候变化的生态影响及适应对策的评估结果,并参考其他文献,介绍了有关中国的相关研究进展。第六次评估报告和相关研究表明,全球气候变暖及其引发的生态影响是十分显著的,主要包括:物候提前,植物生长季延长;物种分布区向极地移动或向高海拔地区移动、树线升高;物种局地灭绝或栖息地退缩;疫病发生频次或强度升高、范围扩大。这些生态影响在不同地区、不同类群间存在一定差异。全球要进一步采取必要的适应和减缓措施,应对不断加剧的气候变化对人类及其赖以生存的生态系统所带来的破坏与挑战。第六次评估报告和相关研究对我国如何应对气候变化也具有重要启示作用。为制定和提出科学合理的气候变化应对和缓解对策,我国急需进一步加强气候变化生态学及对策研究。  相似文献   

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