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1.
The distinct characters of the flower of Plagiostachys elliptica, S. Q. Tong et Y. M. Xia are: (1) each flower possesses two large lateral staminodes, which are adnate to the lip (labellum) to form a deeply 3 lobed labellum;(2) connective extends into a curved, beak like conspicuous appendage (anther crest) and envelops the upper part of style. In the Zingiberaceae, these characters are only present in the genus Zingiber.Furthermore, in Sect. Pleuranthesis of Zingiber the spike also arises from side of the leafy stem. Pollen grains of the species are with cerebelloid sculpture,that is the character of the Subtype Cerebelloid areolate in Zingiberaceae, and are similar to those sculpture and morphology of Sect. Zingiber of the genus Zingiber and differ from those of Plagiostachys, of which pollen grains are with longer spines and belong to the Group long spinate of Subtype spinate. The endotesta of seeds in this species is composed of one layer of brick shaped parenchymatous cells, which is similar to the parenchymatous endotesta of Zingiber seeds and obviously differs from that of seeds of Plagiostachys, which consists of one layer of sclereids. Therefore,Plagiostachys elliptica S. Q. Tong et Y. M. Xia should be transferred from Plagiostachys to the genus Zingiber, and a new combination——Zingiber ellipticum (S. Q. Tong et Y. M. Xia) Q. G. Wu et T. L. Wu is made in this paper.  相似文献   

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Some critical comments are made on the “Eight-Classs System” of the classification of angiosperms recently proposed by Wu et al., which the aut hors claimed to be a “polyphyletic-polytopic” system. This system is established based on the hypothesis that there have existed eight principal lineages of angiosperms by the end of the Early Cretaceous. However, this hypothesis has not been supported by any neobotanical and paleobotanical evidence. There lationship among the eight lineages and their relationship with the common ances tor of angiosperms are not clearly clarified in the system. Having failed to follow the principle of common ancestry in the reconstruction of angiosperm phylogeny and having misinterpreted the concepts of monophyly and polyphyly, the “Eight-Class System” of the classification of angiosperms is considered to be an artificial one.  相似文献   

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Twenty-seven species of the genus Coleophora Hübner (Lepidoptera, Coleophoridae) are recognized in the Korean peninsula, including seven species that are new to Korea: C. albicans Zeller, C. falkovitshella Vives, C. honshuella Baldizzone & Oku, C. japonicella Oku, C. kononenkoi Baldizzone & Savenkov, C. rectimarginalis Li, and C. vestianella (Linnaeus). For all known species, bibliographies, collecting localities, distribution, biological information, and some taxonomic notes are provided, with illustrations of the male or the female genitalia.  相似文献   

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Pollen grains from 15 species (18 taxa) of the genus Filipendula were examined with light and scanning electron microscopy. It was revealed that the pollen grains are isopolar, tricolporate, with scabrate or scabrate-microechinate surface. The pollen morphology was compared with the conventional classification systems of the genus by different authors, and supported Shimizu's system (1961), in which the genus was divided into three subgenera. The monotypic subgen. Hypogyna is characterized by pollen lacking fastigium and thickened costae colpi. The other monotypic subgen. Filipendula differs from others by pollen having larger grain, larger pore size, longitudinally elliptic fastigium and thickened costae colpi. The largest subgen. Ulmaria is distinguished by pollen having rounded or latitudinally elliptic fastigium and thickened costae colpi. Sectional classification was not supported by the pollen morphology due to insufficient variability. Key words Filipendula, palynology, systematics.  相似文献   

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As a genus, Aleuritopteris was first founded by Fée upon Pteris farinosa Forsk. in 1852. The genus had been ever since, however, practically forgotten, because it did not receive a general recognition among the fern students, who considered it either as Cheilanthes (Baker. 1897, Diels, 1900, C. Christensen 1905), or placed it in Pellaea (Hooker. 1858, Hope et Wright 1903). Ching (1941) first reinstated the status of Aleuritopteris and later followed by Copeland (1947), Panigrahi (1961, 1962.) and Pichi-Sermolli (1975). In recent years, however, some pteridologists (Nayar, 1962, K. Iwatsuki and others) are still against it as a distinct genus. Our recent study of the rich material on hand has shown Aleuritopteris to be a distinct genus, according to both the morphological characteristics and geographical distribution. We further propose the possibly evolutionary relationships of Aleuritopteris with other related genera of the Cheilanthoid ferns, as indicated by the above scheme. The genus is now represcented by a little more than 30 species, of which 25 areknown in China, among which 8 species and 3 varieties are diescribed for the first time.  相似文献   

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In his important contribution to the literature on gymnosperm phylogeny, “Basic Features of Gymnosperm Systematics and Phylogeny as Evidenced by the Fossil Record,” Meyen (1984) uses the classical comparative method of the morphologist and the “congregational” method, i.e., grouping by common characters, of the taxonomist. The latter may have led him to categorize some taxa on the basis of superficially similar, non-homologous characters because he used no apparently objective method to distinguish homoplasy. For this and other reasons, Meyen’s hypothesis of evolutionary relationship among gymnosperms cannot, at present, be accepted as any nearer the truth than several competing proposals. The major innovation of Meyen’s proposed phylogeny is the recognition of the clade, Ginkgoopsida, coordinate with Cycadopsida and Pinopsida. Ginkgoopsida encompasses Calamopityaceae, Callistophytales, Glossopteridales, Peltaspermales, Caytoniales, and Ginkgoales, among others. These taxa are considered to be related because, in Meyen’s view, they share the common character of primary platyspermy — i.e., the presumed platyspermic seed-type of the basal group, Calamopityaceae, is considered to have evolved directly from the pteridophytic condition of an ancestral form. This basis for Ginkgoopsida is weakened by the facts that no seeds have been discovered in organic connection with any calamopityacean and, except for the poorly-preserved seed-like structure,Spermolithus, all seeds that occur earlier in the geologic record than fossils of the Calamopityaceae are radiospermic. It is possible, therefore, that even if the platyspermic seed,Lyrasperma, found in association with the calamopityacean,Stenomyelon, were borne by that plant, it is secondarily platyspermic, having evolved from a radiospermic ancestor. The foundation upon which Ginkgoopsida was erected seems, therefore, to be rather tenuous. Other characters used by Meyen, both reproductive and vegetative are discussed. Some which he considers significant, are interpreted to be unimportant in denoting phylogeny, while others are interpreted to support alternative hypotheses. Meyen proposes that the Ginkgoopsida evolved from archaeopterid progymnosperms. This viewpoint seems to be based largely on his erroneous belief thatArchaeopteris was probably a seed plant that bore compound leaves. There is no definitive evidence that supports the view thatArchaeopteris bore seeds. On the other hand, there is strong evidence to support the contention thatArchaeopteris produced simple leaves (Carluccio et al., 1966; Beck, 1971), not compound leaves. Meyen’s phylogenetic proposal is based on data that can be and, in part, have been differently interpreted by others. Consequently, it deserves the careful and critical evaluation of all students of gymnosperm phylogeny.  相似文献   

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In this paper, we analyzed the phylogeny of the section Bulbocodii (genus Narcissus; Amarillydaceae) using the matK and trnL-F fragments of cpDNA in order to review the validity of the recognized taxa. Our results indicate that Narcissus obesus should be considered a valid species, and that N. blancoi is a distinct taxon. In addition, seven previously recognized species, N. juressianus, N. subnivalis, N. graellsii, N. conspicuus, N. citrinus, N. nivalis, and N. quintanilhae, should be assigned to an infraspecific rank under N. bulbocodium, as they are not valid species. In addition, we analyzed the distribution of the three morphological characters widely used in the systematics of this section and found that their variation does not agree with the phylogenetic results, rendering these characters limited taxonomical utility. This result suggests that the section Bulbocodii shows high morphological lability, which can explain the proliferation of nominal species.  相似文献   

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The genus Lasinus Sharp, 1874 of the Pselaphodes complex of genera (Pselaphitae: Tyrini: Tyrina) is revised. The three so far known species, Lasinus mandarinus Raffray, 1890, Lasinus monticola Sawada, 1961 and Lasinus spinosus Sharp, 1874 are redescribed. Eight new species, Lasinus sinicus sp. n. from China, Lasinus mikado sp. n., Lasinus yamamotoi sp. n., Lasinus inexpectatus sp. n., Lasinus yakushimanus sp. n., Lasinus amamianus sp. n., Lasinus saoriae sp. n., and Lasinus okinawanus sp. n. from Japan, are described. And all species are illustrated. Lectotypes are designated for Lasinus mandarinus and Lasinus spinosus. An identification key to species of the genus Lasinus is provided.  相似文献   

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A checklist of 30 species ofEndotricha Zeller in China is presented in this paper. Six species (E. dumalis sp. nov., E. lunulata sp. nov. E. medogana sp. nov., E. nigra sp. nov., E. purpurata sp. nov. and E. simipunicea sp. nov.) are new to science and three (E. admirabilis Kirpichnikova, E. fuscobasalis Ragonot and E. valentis Kirpichnikova) are recorded for the first time in China. The adult features and genital structures of the new species are illustrated and a key to the Chinese species is given.  相似文献   

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The practicability of Vaughan Martini and Martini's Taxonomic Key for the Genus Saccharomyces for the separation of S. bayanus from other Saccharomyces sensu stricto species was studied. It was concluded that the ability to grow in vitamin free medium was not a suitable character for this purpose. A new wild S. bayanus strain, isolated from exudate of Carpinus betulus was also included in this study. This appears to be the third documented strain of that species isolated outside of an artificial fermentation environment.  相似文献   

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Summary According to the hypothesis of Eccles and Libet, the small intensely fluorescent cells (S.I.F. cells) in the sympathetic ganglion would represent an essential element in the inhibition of the principal neuron. As a contribution to the study of this important problem, we have investigated serial sections in superior cervical (S.C.G.) and celiac (C.G.) ganglia of the cat, a species that has not been extensively studied up to now, both by fluorescence and electron microscopy. We have shown that the S.I.F. cells are three times fewer in the cat S.C.G. than in the rat S.C.G. There are five times more S.I.F. cells in the C.G. of the cat than in the S.C.G. of the same species. Moreover we have described two types of S.I.F. cells.Type I is composed of cells characterized by highly polymorphous large dense-cored vesicles. These cells lack processes and are grouped in clusters centered on fenestrated capillaries. They could be endocrine function cells. Type II is formed of isolated cells which exibit long processes and establish synaptic junctions with the dendrites of the principal neurons. In this case, the dense-cored vesicles are very regular and much smaller. These cells could be equivalent to interneurons. Type I very strongly predominates in the S.C.G. and C.G. of the cat where it represents more than 90% of the S.I.F. cell total observed by fluorescence microscopy. A priori such a quantitative and qualitative heterogeneity hardly consistent with Eccles and Libet's hypothesis based on the existence of dopaminergic interneurons only, allows the question to be raised as to the functional significance of the S.I.F. cells in ganglion physiology. The notion of modulation of ganglionic transmission does not seem to be quiered by these new data but could be founded on different forms of action embodied in the broader conception of the neuromodulation phenomenon.  相似文献   

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