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1.
(1) The systematic positions of Clematis potaninii Maxim., C . heynei Rau, C. trichotoma Nakai, C. apiculata Hook. f. & Thoms, C. theobromina Dunn, C. sigensis Engler,C. hedysarifolia DC., and C. dissecta Baker, and the specific status of C. trifida Hook, C.pimpinellifolia Hook., C. oligophylla Hook., and Clematopsis lineariloba Hutch. are discussed; (2) New classifications for Clematis parviloba Gardn. & Champ., C. puberula Hook. f. & Thoms., and sect. Naraveliopsis Hand.-Mazz. are provided; (3) Clematis subsect. Potaninianae M. Johnson, C. heynei M. Johnson, C. petelotii Gagnep. and some other names are reduced to synonymy; (4) Two subsections, 4 series, 4 species, and 4 varieties are described as new; (5)Four new ranks and 4 new combinations are made.  相似文献   

2.
(1) Clematis taiwaniana Hayata, C. grata Wall. var. ryukiuensis Tamura, C . sikkimensis (Hook. f. & Thoms. ) Drumm. ex Burkill, C. connata DC. var. bipinnata M. Y. Fang, C. kilungensis W. T. Wang & M. Y. Fang etc. are reduced to synonymy. (2) New classifications for sect. Tubulosae Decne., C. siamensis Drumm. & Craib and C. connata DC. are proposed. (3) 3 series, 3 species and 4 varieties are described as new. (4) 6 new combinations and 3 newranks are made.  相似文献   

3.
(1) The evolutionary trends of sepals and stamens of the genus Clematis are discussed; (2) New classifications for sect. Cheiropsis DC. and sect. Aspidanthera Spach are proposed; (3) One subsection, 13 series, 5 species and 4 varieties are described as new; (4) Six new ranks and2 new combinations are made.  相似文献   

4.
Clematis sect. Clematis is revised in this paper. Seventy-three species and 45 varieties are recognized. They are keyed, described, and illustrated in some cases, and are classified into five subsections. Brief taxonomic history and geographical distribution of the section are given, and the relationships of its subsections and with its close allies of the C. vitalba evolutionary stock of the subgenus Clematis are discussed. Main taxonomic changes are made as follows: (1) C. lancifolia Bur. & Franch., C. songarica Bunge, C. ispahanica Boiss., C. delavayi Franch. and C. phlebantha Williams, which have been previously regarded to be close to C. fruticosa Turcz. and its allies, and placed in sect. Fruticella Tamura by Tamura and some other authors, are here transferred to subsect. Angustifoliae Tamura according to the floral structure. (2) The existence of intermediate forms between the C. vitalba group and the C. flammula group indicates that these two groups are closely related to each other and should not be treated as two sections or even two subgenera. They are treated as two subsections within sect. Clematis . Two series, six species, and one variety are described as new, and five new ranks are made.   相似文献   

5.
In 1929, V. F. Brotherus published eight species and one form of Chinese Brachytheciaceae based on Handel-Mazzetti's collections from Hunan, Guizhou and Yunnan provinces of China during 1914~1918. The holotypes of all the taxa mentioned above were studied by the present authors. Three names are newly reduced to synonyms: Brachythecium subcurvatulum≡ Brachythecium velutinum ; Rhynchostegium gracilescens≡ Eu-rhynchium savatieri and Rhynchostegium obsoletinerve≡Herzogiella turfacea.  相似文献   

6.
The genus Byssosphaeria from China was briefly reviewed based on specimen examinations and literature work. Taxonomic and nomenclatural problems are discussed. Among the previously recorded taxa of the genus, a new combination, Byssosphaeria hainanensis, is made and a new Chinese record, B. alnea, is reported. A key to the known species of the genus in China is provided.  相似文献   

7.
Clematis sect. Atragene is revised in this paper based on the examination of a large number of herbarium specimens, extensive field observations, and morphometric analyses. Brief taxonomic history and geographical distribution of the section are given, the relationships among the species are discussed, and the evolutionary trends of some characters in the section are evaluated. The staminodes of the plants in this section may have evolved from the outer stamens with petaloid filaments and gradually disappearing anthers. Subsequently, they may have evolved in two different ways. One possibility is that the staminodes elongate and become lanceolate, as long as sepals, and their apices turn into attenuate. The other is that the staminodes are spathulate, but not elongating, as long as stamens, and their apices turn into retuse from obtuse and rounded. The evolutionary trend of sepals may be from thin to thick in texture, and the veins from non-prominent to prominent. As a result, five new series are established and nine species, two subspecies and nine varieties (including three new ranks) are recognized in this section. An identification key is provided, and each taxon is described and illustrated. Clematis sibirica and Clematis ochotensis are treated as subspecies of Clematis alpina due to their subtle differences and lack of, or few, overlapping distributions. Clematis fusijamana and Clematisfauriei are recognized as varieties of C. alpina ssp. ochotensis for the continuous variation of the velutinous strips on the sepal margins. Clematis iliensis is treated as variety of C. alpina ssp. sibirica for the continuous variation of leaf division types. Extensive variations in sepal color and basal caruncle size support degrading Clematis chiisanensis as a variety of Clematis koreana. The North American ser. Occientales may be primitive, whereas ser. Macropetalae may be the most advanced taxon in this section. Ser. Alpinae and ser. Koreanae are closely related to each other. However, the systematic position of ser.  相似文献   

8.
Background: Various rare and endangered temperate ferns are being threatened by their recent population decline, but there is limited understanding of the causes behind it.

Aims: This study attempted to identify the possible drivers of regional population decline and extinction in the globally distributed woodland fern Polystichum braunii.

Methods: A comparison was undertaken of the climatic, edaphic and phytosociological characteristics of sites with increasing, decreasing or recently extinct populations in Germany.

Results: A significantly higher frequency of episodes of low relative air humidity (<60%) was found at sites with decreasing or extinct populations compared to habitats with population increases. Sites with decreasing or extinct populations were also characterised as having less summer precipitation (<500 mm year?1) and a shorter duration of snow cover (<110 days year?1) than sites with increasing populations. The latter had significantly higher moss cover (56% of the forest floor), but less cover by a tree litter layer (23%) compared to decreasing (36% and 38%) or recently extinct populations (22% and 52%). All increasing populations were located in intact TiliaAcer ravine forests, while those suffering population decline were mostly located in Fagus-dominated forests.

Conclusions: It was concluded that the probable causes of the recent decline in German P. braunii populations are reduced air humidity levels, decreasing snow duration or a shift from moss-covered to tree litter-covered forest floors due to climate warming or altered forest management.  相似文献   

9.
A strict consensus tree based on chloroplast and nuclear sequences (rbcL, matK, trnL, FLint2) from 46 Amorphophallus species, two Pseudodracontium species and six outgroups is used to develop a hypothesis for the evolution of ornamentation and ectexine ultrastructure in the pollen of Amorphophallus. There are four main clades: an exclusively African, largely psilate clade (‘African clade’), an Asian, largely psilate clade (‘Asian psilate clade’) and an Asian, largely striate clade consisting of a mainly continental SE Asian clade (‘continental SE Asian striate clade’) and one centred in Malesia (‘Malesian striate clade’). Ultrastructure provides a valuable contribution towards understanding pollen ornamentation in Amorphophallus. Pollen with a thin psilate ectexine without dark granules might be plesiomorphic in Amorphophallus. Then the diverse striate type would be derived. Within both striate clades, reversals to the psilate type occur. Striate pollen with psilate caps, which is nested in the continental SE Asian striate clade, is a synapomorphy of Pseudodracontium. The fossulate type is also diverse, and its distribution in the tree indicates a polyphyletic origin. Areolate, echinate and verrucate ornamentation, occur in single species in the tree, but are found also in species not included in the molecular analysis. All three are heterogeneous and probably polyphyletic too. Reticulate, scabrate and striate/scabrate ornamentation are autapomorphies, of which the reticulate type and the striate/scabrate type may derive from psilate and striate ornamentation, respectively. Of the four main clades, the Asian psilate and African clade seem to be basal, while both striate clades might have evolved from the Asian psilate clade via a species like A. rhizomatosus. Dark granules evolved more than once, which might explain their diverse size, shape and distribution.  相似文献   

10.
11.
Myrmecia dispar (Clark) is found in the drier inland areas of New South Wales and southern Queensland in Australia. Its nests, which are situated adjacent to trees, have a distinctive structure of simple architecture. The composition of the colonies varies seasonally with little or no brood production during the colder months. Colony founding probably takes place in March, April, and/or May. Several myrmecophiles are found in nests ofM. dispar, and some of these are present in relatively large numbers.  相似文献   

12.
Many phylogeographic studies of terrestrial plant species on the Qinghai–Tibet Plateau (QTP) have been carried out to elucidate the range shifts in response to climatic oscillations in the Quaternary. However, patterns of range shifts for aquatic plants following the climate change on the QTP are poorly understood. Here, we studied the historical range shifts of the aquatic herb Ranunculus bungei Steud. on the QTP using four chloroplast (cpDNA) non-coding spacers. We revealed low within-population genetic diversity (HS = 0.052) and high interpopulation genetic differentiation (GST = 0.914; NST = 0.954). But the high population differentiation was not coupled with a distinct phylogeographic structure (NST > GST, P > 0.05). Phylogenetic analyses revealed two main cpDNA haplotype lineages and the split between these two lineages can be dated back to the late Tertiary (3.84–11.90 Ma). Two independent range expansions within the two intraspecific lineages at approximately 0.15–0.46 and 0.17–0.50 Ma were revealed. Our results suggested that R. bungei survived the Last Glacial Maximum and/or previous glacial periods on the QTP. Colonization or recolonization during the repeated range expansions may have replaced the early haplotypes and the pre-existing genetic structure and could explain the non-significant phylogeographical structure.  相似文献   

13.
Komala Z 《Folia biologica》2000,48(1-2):47-48
The seepage of water on the Gubernasówka clearing in the forest (alt. about 850 m) was investigated from the point of view of the occurrence of the Paramecium aurelia species complex and other zooplanktonic organisms. Though, none of the species of the complex was found, another morphological species of the Paramecium genus, i.e. Paramecium caudatum was registered.  相似文献   

14.
Notes on the Poaceae of the Robinson Crusoe (Juan Fernández) Islands, Chile, Brittonia 54: 154–163. 2001.—Poaceae in the Robinson Crusoe (=Juan Fernández) Islands number 53 species in 32 genera, of which 9% of the species are endemic, 9% indigenous, and 81% adventitious. The endemic taxa (and their conservation status) are:Agrostis masafuerana (rare),Chusquea fernandeziana (not endangered),Megalachne berteroana (not endangered),M. masafuerana (not endangered), andPodophorus bromoides (extinct).Megalachne andPodophorus are endemic genera. Comparisons with Poaceae in the Bonin and Volcano Islands, Canary Islands, Galápagos Islands, and Hawaiian Islands show different levels of endemism: number of endemic taxa, respectively, 5, 10, 12, 40; percent specific endemism, 8, 6, 21, 19. No endemic genera occur.Anthoxanthum odoratum, Avena barbata andHordeum murinum are noxious weeds in the Robinson Crusoe Islands. Many adventives are shared among floras of the archipelagos, with the highest ties of Robinson Crusoe being to the Canaries (53% of total Poaceae known in Juan Fernández) and the Hawaiian Islands (47%). Low levels of adventives occur within the Bonin (5%) and Galápagos (7%) Islands. In contrast, there are many endemic genera of Asteraceae in these same archipelagos: Bonin and Volcano Islands (1), Canary Islands (8), Galápagos Islands (5), and Hawaiian Islands (6); percent of specific endemism is also higher (20, 53, 54 and 56, respectively). Hypotheses for greater levels of endemics among oceanic island Asteraceae include more efficient dispersal mechanisms by wind and birds, animal pollination systems that result in greater degrees of geographic populational genetic isolation, and a vascular cambium that offers enhanced growth-form evolutionary opportunities.  相似文献   

15.
A new depsidone 1′-chloropannarin has been isolated from the lichen Argopsis friesiana Müll. Arg. and synthesized by chlorination of pannarin. A revised structure of pannarin, and notes on the chemical constitution of Argopsis friesiana Mill. Arg. A. megalospora Th. Fr., are given.  相似文献   

16.
红花铁线莲(Clematis coccinea)的组织培养   总被引:3,自引:0,他引:3  
红花铁线莲为毛茛科铁线莲属藤本植物、具有较高的观赏价值,也是极好的垂直绿化材料。但因其结实少,依靠种子繁殖很困难,而用其它方法繁殖,繁殖系数也很低。由于不能获得大量苗木,所以长期以来,红花铁线莲不能得到广泛栽培应用。随着组织培养技术的发展,通过植物组织离体培养来进行快速繁殖,目前在很多种园林植物上得到了应用。但红花铁线莲的组织培养,尚未见报道。本文简要报道了铁线莲茎、叶  相似文献   

17.
对毛茛科铁线莲属Clematis L.的单性铁线莲组sect. Aspidanthera Spach s.l.进行了全面修订,确定此组共含72种和15变种,这些种被归类于6个亚组中,其中包括首次描述的1系、5种和2变种,以及做出的2新等级.对单性铁线莲组的分类学简史和地理分布做了介绍.写出了组、亚组、系的形态特征和地理分布,分亚组检索表及各亚组的分种检索表;以及各种植物的形态描述、地理分布、生长环境等,并附有多幅插图.在研究了此组全部种类的标本之后,观察到此组几个重要形态特征的演化趋势(1)萼片在数目上由4枚演变到8枚,在开展方向上由平展到直上展,在形状上由长圆形到狭条形,在长度上由比雄蕊稍长到2-4倍长于雄蕊,其卷叠式由镊合状到次生的覆瓦状;(2)花药药隔顶端由不具突起到具短或长的突起;(3)雌花退化雄蕊的数目由多数到定数、少数,以至完全消失;(4)花序自当年生枝的叶腋发生演变到与数叶同自老枝的一腋芽中发出.根据上述演化趋势推断本组各亚组间的亲缘关系如下subsect. Dioicae (34种,广布于北美洲和南美洲)的花构造(萼片4,镊合状排列,平展,通常呈长圆形,稍长于雄蕊或近等长,外面边缘被短绒毛;雄蕊花药呈长圆形,药隔顶端无突起;雌花具多数退化雄蕊;花序自当年生枝的叶腋发出)与具两性花的威灵仙组欧洲铁线莲亚组sect. Clematis subsect. Clematis 的花极为相似,区别主要在于本亚组的花为单性,由此判断subsect. Dioicae可能是单性铁线莲组sect. Aspidanthera的原始群,源出于欧洲铁线莲亚组.本组的第二亚组subsect. Lasianthae(2种,分布于北美西南部)与subsect. Dioicae 在亲缘关系上极为相近,区别只在于其花序或具花当年生枝与数叶一同由老枝的一个腋芽中发出,此亚组当是从subsect. Dioicae衍生出的一个小群.第三亚组subsect. Microphyllae(7种,特产澳大利亚)也与subsect. Dioicae相近缘,但此亚组的萼片变狭长,多呈条形或狭条形,常2-4倍长于多少变短的雄蕊,雌花的退化雄蕊数目变少,16-2枚,根据这些进化特征,推测此亚组也源出于subsect. Dioicae.第四亚组subsect. Aristatae (16种,分布于澳大利亚、新几内亚及邻近岛屿)与subsect. Microphyllae 在亲缘关系上相近,但本亚组的花药药隔顶端具短或长的突起而不同,根据此进化特征,推测本亚组系由后者演化而出.第五亚组subsect. Hexapetalae (11种,特产新西兰)的花构造与分布于澳大利亚的subsect. Microphyllae相似,但其萼片为覆瓦状排列,外面边缘不被短绒毛,在多数种多于4枚,为5-8枚而不同.据Godley 的研究,本亚组中的C. afoliata的花有4枚萼片,排成2轮,每轮的2枚萼片均为近镊合状排列;另外,在C. paniculata花的6枚萼片中,4枚为覆瓦状排列,其他2枚有时内向镊合状排列.从上述情况可见此亚组的萼片覆瓦状卷叠式可能是由镊合状卷叠式演变而来的一种次生现象,并由此推测,此亚组可能与subsect. Microphyllae相同,也源自美洲的subsect.Dioicae.最后一个亚组subsect. Insidiosae(2种,特产马达加斯加)的雌花萼片直上展,退化雄蕊完全消失,具有这些进化特征,当是单性铁线莲组的进化群,可能源出自具定数或少数退化雄蕊的subsect. Microphyllae.  相似文献   

18.
The genusGonocalyx, hitherto known from Hispaniola, Puerto Rico, Dominica, and Colombia is recorded from Central America. Two species are described from Costa Rica, one (G. costaricensis) is new to science. A key to the seven species of the genus is provided.  相似文献   

19.
20.
The motacú palm (Attalea phalerata) is widespread in Bolivia and is an economically valuable species as a source of vegetable oil. In Bolivia it is utilized as construction material, food, medicine, cosmetic, and edible oil. Oil extracted from the kernel (60–70% of dry weight) is high in lauric and myristic oils and compares favorably with other tropical oil crops. The palms reach reproductive maturity in 7–10 years and potential oil production from cultivated stands is 1.1-2.4 tons/ha/yr.  相似文献   

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