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1.
《Journal of bryology》2013,35(1):56-68
Abstract

A new species of Pseudocrossidium R.S.Williams, P. exiguum M.J.Cano &; J.A.Jiménez, is described from South America (Argentina, Brazil and Peru). The species is distinguished morphologically by its lingulate to oblong-ovate leaves, leaf marginal cells not or scarcely differentiated from inner, costa ending below apex or percurrent, and semicircular to elliptical in cross-section with two guide cells, scarcely differentiated perichaetial leaves and peristome of short and straight teeth. Drawings and light microscope photographs of the new species are provided. The principal distinctive characters that separate it from the nearest species of Pseudocrossidium and related genera are discussed.  相似文献   

2.
A new species of Plagiomnium (Mniaceae), P. guizhouense Y.-J.Yi & S.He from Guizhou, China is described and illustrated. The new species is similar to P. affine in having spinosely serrate leaf margins with teeth consisting of up to 4 or more cells, a broadly elliptic leaf shape, and a decurrent leaf base, but is distinguished from the latter species by having a cuspidate leaf apex, broader marginal differentiation with borders consisting of 4–5 rows of linear, thick-walled cells, strongly ciliate marginal teeth that are sometimes branched and up to 7 cells long in upper fertile stem leaves and perichaetial leaves, and a much shorter leaf costa that ends just above mid-leaf in the lower leaves.  相似文献   

3.
Carex yandangshanica C. Z. Zheng & X. F. Jin, a new species of Carex sect. Rhomboidales Kükenth. from Zhejiang, China, is described and illustrated. The new species is similar to C. thibetica Franch. and C. brevicuspis C. B. Clarke, but differs from the former by having trabeculate leaves, pistillate spikes with 6–10 staminate flowers or without staminate flower at the apex, and achenes at apex contracted into a slightly curved beak, and from the latter by having lateral culms, trabeculate leaves, and elliptic, rubiginous and awned pistillate scales. SEM microphotographs of perigynia and achenes are provided for the new species and related taxa.  相似文献   

4.
Two new species, Syzygium humbertii Byng and S. mortonianum Byng, are described from Madagascar. When compared with other Madagascan Syzygium, S. humbertii Byng is characterised by sessile to subsessile leaves, orbicular to oval blades with usually cordate bases and rounded apices, and an obconic hypanthium. Syzygium mortonianum Byng is characterised by relatively long leaves that are typically wrinkled when dried, widely spaced venation, long petioles, and particularly dense capitate inflorescences with many flowers. Both new species are threatened with extinction and known from few contemporary collections.  相似文献   

5.
Primula jiugongshanensis J. W. Shao, a new species from Mt Jiugongshan in Hubei Province, China, is described and illustrated. This species is a biennial glabrous herb with pinnately compound leaves, and affiliated to P. sect. Ranunculoides C. M. Hu. It is distinguished from other species of the section by outer simple leaves ovate, flowers distylous, corolla lobe apex conspicuously emarginate, and lack of bulblets. Molecular phylogenetic analysis of nrDNA internal transcribed spacer sequences (ITS) was conducted and the results also supported the recognition of P. jiugongshanensis as a new species. The species is known from only three separated unprotected populations and is categorized as ‘Endangered’ (EN).  相似文献   

6.
Manihot allemii M. J. Silva is described and illustrated as a new species, and its morphological affinities and conservation status is discussed. It is most similar to M. salicifolia Pohl in having a subshrubby and erect habit and in the general aspect of its unlobed leaves, but differs from it in having leaves that are conspicuously petiolate, an inflorescence that is a congested spike‐like thyrse, entire and diminute bracts and bracteoles subtending flowers of both sexes, pistillate calyx that is deeply lobed with oblong lobes, and staminate flowers with 8 or 10 stamens. Both species belong to a group of 14 species recognized by their possession of entire and unlobed leaves, which are the subject of taxonomic studies by the second author. Some notes on the leaf anatomy of species of Manihot that have entire and unlobed leaves are also presented.  相似文献   

7.
Turbinaria foliosasp. nov. is described on the basis of several collections made from Dhofar, Sultanate of Oman. The new species is known only from southern Oman, a region of the northern Arabian Sea that is strongly impacted by the upwelling from the summertime monsoon. It is distinguished from other species of the genus by the shape of the leaves and by their loose, non‐congested arrangement. Air vesicles, embedded in the leaves, may be present, but more often are absent. A census of the currently recognized species in the genus Turbinaria is provided. Reference is made to Sargassum turbinarioides and Sargassum turbinati‐folium. These species possess discrete blades and spherical vesicles and thus conform to Sargassum.  相似文献   

8.
Microstachys crassifolia, a new species from Chapada dos Veadeiros region in the State of Goias, central Brazil, is here described and illustrated. Its habit and general morphology resembles that of M. nana Silva & Esser, an endemic species from the State of Paraná, southern Brazil. Both species are hemicryptophytes from grasslands, with a well‐developed underground system, glabrous leaves and reddish inflorescences and fruits, but M. crassifolia has fleshy leaves without glands while M. nana has membranaceous leaves with pateliform, submarginal glands.  相似文献   

9.
The genus Dendromyza (Amphorogynaceae) comprises approximately 21 species with a distribution from the Malay Archipelago to southern Australia. Two new hemiparasitic species in this genus: D. hiepkoana from Irian Jaya and D. staufferi from Papua New Guinea are here described, illustrated and compared. Dendromyza hiepkoiana is similar to members of the genus Phacellaria (Benth.) where the leaves are very small and bract‐like, but differs in its separate stigmas and chambered fruits that possess a crown of fibers on the endocarp. Dendromyza staufferi is allied to D. reinwardtiana (Bl. ex Korth.) Danser but differs from this species by broader, ovate rather than narrower, spathulate leaves and sessile inflorescences. Dendromyza staufferi also has an ovoid rather than elliptical endocarp and the crown of fibres at the apex of the endocarp are pilose. Due to their hemiparasitic nature and aerial habitat, species of Dendromyza are generally considered to be vulnerable in terms of conservation status. Based on the information available to us, however, the species described here are categorised as locally common or near threatened.  相似文献   

10.
Summary In order to study the foliar endophytes from teak (Tectona grandis L.) and rain tree (Samanea saman Merr.) growing in the campus of Chulalongkorn University, healthy leaves were collected at two-monthly intervals during January to December. The number of genera and species, together with their colonization frequency (CF%) in mature teak and rain tree leaves were greater than those in the young leaves. More endophytic isolates in the leaves of both trees were recovered during the rainy season. The fungal genera found in both young and mature teak leaves were Alternaria, Colletotrichum, Nigrospora, Phomopsis and mycelia sterilia. Phomopsis was the dominant genus in both young (newly emerged) and mature leaves. Fusarium, Penicillium, Schizophyllum commune and members of the Xylariaceae were found only in mature leaves. For the rain tree leaves, species of Phomopsis and mycelia sterilia were found in both young newly emerged and mature leaves. Colletotrichum and Penicillium were found only in mature leaves, whereas Nigrospora was found only in young newly emerged leaves. In this study, Phomopsis was the dominant genus in the leaves of both tree species. A total of 37 isolates of endophytic fungi isolated from teak and rain tree leaves were tested for the production of antimicrobial activities. Out of these, 18 isolates could produce inhibitory substances effective against Bacillus subtilis, Staphylococcus aureus and Escherichia coli and 3 isolates inhibited growth of Candida albicans in vitro.  相似文献   

11.
A new Sciadopitys-like conifer is described on the basis of compression fossils of shoots and leaves found at the Smokey Tower locality in western Alberta. The specimens consist of long, strap-like leaves attached in apparent whorls and subtended by groups of scale leaves. Other scale leaves are borne in loose spirals on the shoots between whorls. These specimens represent the first record of Sciadopitys-like foliage from western North America. Comparisons are made with extant and extinct species of the genus Sciadopitys (Siebold and Zuccarini, 1841) and with the widely distributed fossil genus Sciadopitytes (Goeppert and Menge, 1883).  相似文献   

12.
Cephalaria kleinii Ranjbar & Z. Ranjbar sp. nova from Iran is described and illustrated. It is confined to Mazandaran province in northern Iran. The new species is closely related to C. kotschyi Boiss. & Hohen., but differs from it by its abaxial leaves colour, its basal leaves shape, dissection and petiole length, by the shape of apices of lateral and terminal segments of the cauline leaves, by the shape of apices of lateral and terminal segments of the upper leaves and by peduncle length. Furthermore, C. axillaris is resurrected and lectotypes are designated for C. axillaris and C. kotschyi for the first time.  相似文献   

13.
A new species, Ranunculus giordanoi, belonging to the R. auricomus complex is described from Latium, central Apennines (Italy). It grows in damp meadows on Monti della Laga (National Park of Gran Sasso and Monti della Laga), the largest sandstone massif of central Italy. The new species differs from the closely related R. silanus, endemic to Sila (Calabria, southern Apennines), by leaf aperture, shape of the basal leaves, entire or sometimes deeply lobed cauline leaves, gynoclinium without intervallum and longer carpellophores.  相似文献   

14.
Summary Near-isogenic cultivars of Hordeum vulgare which differ for the Mlp gene for resistance to Erysiphe graminis f.sp. hordei were inoculated with race 3 of this pathogen and in vitro translation products of mRNA populations compared by 2-dimensional gel electrophoresis and fluorography. This revealed the presence of new mRNA species in infected leaves compared to non-inoculated controls. These new mRNA species were more abundant in resistant leaves than susceptible leaves. A cDNA library was prepared from poly(A)+RNA isolated from infected leaves carrying the Mlp gene for resistance (cvMlp). The library was screened by differential hybridization using [32P]-labelled cDNA prepared from poly(A)+RNA of both control and infected leaves. Six cDNA clones showing greater hybridization to cDNA prepared from infected leaves were selected. These six cDNA clones hybridized to DNA isolated from barley leaves but not to DNA from conidia of the fungus. In Northern blot analysis of RNA from infected leaves the six cDNA clones each hybridized to mRNA species of different size. Translation products for three of the cDNA clones corresponded to infection-related translation products identified on 2-dimensional fluorograms. The cDNA clones were used to study the kinetics of host mRNA induction during infection of the near-isogenic cultivars of barley. The host mRNA species corresponding to the cDNA clones were induced prior to 24 h after inoculation during the primary penetration processes. In addition the mRNAs corresponding to four of the cDNA clones increased to greater amounts in cvMlp than in the near-isogenic susceptible cultivar (cvmlp) over a 2-d period following inoculation. These results suggest that the Mlp gene has a regulatory role in host gene expression resulting in enhanced expression of several host mRNA species following infection by the powdery mildew fungus.  相似文献   

15.
Erysimum damirliense, a new species of Brassicaceae from Zanjan and Ardebil provinces (northwest Iran) is described and illustrated. The new species resembles E. uncinatifolium and E. elbrusense, but is easily recognized by its life form, basal leaf margin, indumentum of cauline leaves, number of flowers in the main raceme, fruit width and style length. Phylogenetic analysis of internal transcribed spacer (ITS) DNA sequences confirm that the new species is distinct from morphologically similar species.  相似文献   

16.
Leaves in most extant Ephedra ‐species represent only rudimentary scales without chlorophyll. Photosynthesis is completely restricted to green shoots. Only some species, e.g. Ephedra altissima, develop folious leaves even when being mature. Morphology and anatomy of cotyledons, primary leaves, and subsequent folious leaves of Ephedra altissima were examined particularly with special focus on their vasculature. The results show that the reduction of the leaves is achieved by an extreme reduction of the adaxial leaf surface. Most parts of the leaf surface are therefore developed by the abaxial side. Apart from a reduced lamina, a thick cuticle and sunken stomata are the only xerothermic adaptations in leaves of Ephedra altissima. A hypodermis and endodermis are also not developed. The anatomical results indicate that ancestors of modern Ephedra‐ species might have evolved in a more humid climate, contrasting to the arid habitats in which extant Ephedra‐ species are native today. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

17.
Ligularia dalaolingensis, a new species from Hubei and Hunan, China, is described and illustrated. It belongs to L. sect. Ligularia ser. Speciosae on the basis of its palmate leaf venation, racemose synflorescence and pappus which is slightly shorter than the tube of the tubular corolla. In the series, its closest relatives are assumed to be L. fischeri and L. stenocephala. From L. fischeri, L. dalaolingensis is readily distinguished by smaller basal leaves, shorter synflorescence, narrower involucres and fewer phyllaries and florets; from L. stenocephala, L. dalaolingensis differs by smaller basal leaves, shorter synflorescence as well as broader bracts. A diagnostic key to Chinese species of L. ser. Speciosae with broadly ovate, ovate or ovate‐lanceolate bracts is provided.  相似文献   

18.
《Journal of bryology》2013,35(4):677-680
Abstract

Renauldia paradoxica, a new Pterobryaceous moss from western Panama, differs from all other species of Renauldia by its long, narrowly acuminate leaves. This species fits somewhat uncomfortably in Renauldia and appears to occupy a position intermediate between Renauldia, Orthostichidium, and Pterobryopsis.  相似文献   

19.
Protoplasts have been isolated from three tuber-bearing Solanum species, S. hjertingii, S. polyadenium and S. capsicibaccatum, that are sexually incompatible with S. tuberosum, but possess potentially useful characters. For isolating protoplasts from leaves of in vitro shoot cultures of S. hjertingii and S. capsicibaccatum growth was improved by including silver thiosulfate in the medium. However, for S. polyadenium, leaves of pot-grown plants were the best source for protoplasts. Following protoplast division and culture, plants were regenerated from protoplasts of each of the species. The pattern of chromosome variation in regenerants was similar to that observed for other diploid and tetraploid Solanum species. The results indicate that it should be possible to introduce the potentially useful germplasm from these wild species into somatic hybrids with S. tuberosum by protoplast fusion.Abbreviations STS silver thiosulfate - BAP benzylaminopurine - GA3 gibberellic acid - NAA naphthalene acetic acid - IAA indole-3-acetic acid  相似文献   

20.
Two new species of Centaurea L. sect. Cynaroides Boiss. ex Walp. (Asteraceae), C. shahuensis Ranjbar and Negaresh and C. ravansarensis Ranjbar and Negaresh are described and illustrated from Kermanshah Province, west Iran. They are closely related to C. regia Boiss. subsp. regia. However, C. shahuensis differs from it by median stem leaves broadly oblanceolate or subpandurate, phyllaries densely lanate‐tomentose, appendages small, concealing a minor part of phyllaries, and also median appendage margin entire sometimes with 1–2 cilia, 1.2–3.0 mm long on each side. Centaurea ravansarensis is distinguished by upper stem leaves loosely arachnoid, phyllaries loosely floccose‐tomentose, inner appendages deep brown to blackish, and spine 4.5–6.0 mm long. Habitat, conservation status and the geographical distribution of the new species are given.  相似文献   

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