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Summary  Four new species of Asparagus (Asparagaceae) from the Flora Zambesiaca area are described and illustrated; the need for more collections is highlighted to assess their conservation status. Asparagus botswanicus Sebsebe is known from a single locality in Botswana; A. chimanimanensis Sebsebe occurs in Zimbabwe and Mozambique; A. richardsiae Sebsebe is known in Zambia and A. radiatus Sebsebe is from a small restricted area (Goba) in Mozambique and Umbeluzi Gorge in Swaziland.  相似文献   

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Kocyan A 《Annals of botany》2007,100(2):241-248
BACKGROUND AND AIMS: Individual flowers of the monocot Curculigo racemosa (Hypoxidaceae, Asparagales) are regularly polyandrous. To evaluate the significance of this almost unique character among Asparagales for flower evolution of asparagoid monocots, flowers of C. racemosa were studied comparatively. METHODS: Anthetic flowers as well as early floral developmental stages were studied by light and scanning electron microscopy. KEY RESULTS: Despite the polyandry, floral development is similar to that of other Asparagales with a developmental gradient from adaxial to abaxial. Stamens initiate simultaneously and the diameter of staminal primordia is about half of that in species with six anthers. The number of stamens is not fixed (12-26) and varies within the same inflorescence. Surprisingly, the gynoecium can be four- or six-locular, besides the normal trimerous state. CONCLUSIONS: The discovery of a polyandrous Curculigo reveals plasticity of stamen number at the base of Asparagales. Orchidaceae - sister to all other Asparagales - has a reduced stamen number (three, two or one), whereas in Hypoxidaceae - part of the next diverging clade - either the normal monocot stamen number (six), polyandry (this study) or the loss of three anthers (Pauridia) occurs. However, at present it is impossible to decide whether the flexibility in stamen number is autapomorphic for each group or whether it is a synapomorphy. The small size of stamen primordia of Curculigo is conspicuous. It allows more space for additional androecial primordia. Stamens are initiated as independent organs, and filaments are not in bundles, hence C. racemosa is not secondarily polyandrous as may be the case in the distantly related Gethyllis of asparagoid Amaryllidaceae. The increase in carpel number is a rare phenomenon in angiosperms. A possible explanation for the polyandry of C. racemosa is that it is a natural SUPERMAN-deficient mutant, which shows an increase of stamens, or ULTRAPETALA or CARPEL FACTORY mutants, which are polyandrous and changed in carpel number.  相似文献   

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Steyermark  Julian A. 《Brittonia》1975,27(3):251-262
Brittonia - Seven species ofJoosia are recognized, four of which are new:J. ulei,J. aequatoria,J. standleyana, andJ. macrocalyx. All of the species are confined to western South America from...  相似文献   

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Froesia venezuelensis, a new species from Venezuela, is described, and the two previously known species ofFroesia are revised.  相似文献   

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Andrew M. Torres 《Brittonia》1969,21(4):322-331
Philactis (Compositae-Heliantheae) is a genus of three species, all of limited distribution. A revision is presented, based upon herbarium specimens and field work. Cytological data are from bud material fixed in the field, and from root tips of seedlings. The basic chromosome number appears to be 14.P. nelsonii andP. liebmannii are tetraploid (2n = 56), andP. zinnioides is hexaploid (2n = 84).  相似文献   

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The genus Haniffia is revised, in comprises two species of which one is described as new: H. albiflora from Thailand. Both species are illustrated.  相似文献   

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Clibadium L. (Asteraceae, Heliantheae) is a genus of 29 species distributed throughout latin America, from Mexico to Peru, and in the West Indies, with high numbers of species in Costa Rica, Colombia, and Ecuador.Clibadium includes shrubs and small trees; usually with loosely aggregated capitula; herbaceous phyllaries arranged in 1–5 series; receptacles usually paleaceous throughout; corollas of pistillate florets 2–4-lobed; corollas of the staminate florets 4–5-lobed; purple to black anthers; and chromosome numbers alln=16. Two sections of species previously recognized are here considered as subgenera (subg.Paleata and subg.Clibadium) containing two and four sections, respectively.Clibadium subg.Paleata contains five species distributed in sects.Eggersia (3 spp.) andTrixidium (2 spp.), and subg.Clibadium has 24 species distributed among sects.Clibadium (6 spp.),Glomerata (9 spp.),Grandifolia (5 spp.), andOswalda (4 spp.).  相似文献   

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The number of species in Trivalvaria is reduced from eight to four. A new variety of T. macrophylla from North Sumatra is described. Two Polyalthia species, P. nemoralis and P. oligogyna, found in Laos, North Vietnam, and Hainan, are brought into the synonymy of Z dubia. The genus further ranges from NE India and the Andarnan Islands to Java and Borneo. It is distinguished from other Asian Annonaceae by the characteristic venation of the leaves, the imbricate sepals and petals, and the single basal ovule.  相似文献   

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Sageraea consists of 9 species, two of which are newly described: S. sarawakensis from Sarawak and S. zeylanica from Sri Lanka. Its distribution ranges from India to the Philippines and Indonesia. Sageraea is closely related to Stelechocarpus , with which it shares the imbricate aestivation of the sepals and petals. Further characteristics are the usually glabrous plants, the coriaceous leaves, the thick, fleshy stamens, and ovules or seeds in 2 series.  相似文献   

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Abstract

The endemic New Zealand genus Argyrophenga Doubleday is revised. The genus is shown to consist of three species, antipodum Doubleday, harrisi n.sp., and janitae n.sp. Wing pattern, wing coloration, and male genitalia of all species are described and illustrated. Keys to species are given for both sexes. Taxonomic conclusions are supported by biometric and distributional data. Flight behaviour is described. A brief comparison is made between Argyrophenga and the other endemic New Zealand satyrid genera.  相似文献   

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88 species and 20 subspecies ofCarex, altogether 94 taxa, occur in the area ofRechinger's Flora Iranica. Of these, 48 taxa, have an Euro-Siberian, 11 an Irano-Turanian and 35 a Central Asiatic distribution, the last including five species with connections to E. and tropical SE. Asia. The Saharo-Sindian element is missing. Endemic taxa are found in all groups. Eight taxa, endemic to the NW. Himalayas occur in the E. part of the area. The Euro-Siberian taxa are concentrated in the NW. of the area, but have connections to the east; similarly, Central-Asiatic taxa are concentrated in E. Afghanistan and N. Pakistan, but have connections to the west. Some Euro-Siberian taxa are widely distributed in the area, but avoid the most arid regions. The Irano-Turanian taxa are few and extend from Egypt through the area of Flora Iranica to Kazakhstan SSR and Central China.Dedicated to Hofrat Univ.-Prof. DrK. H. Rechinger on the occasion of his 80th birthday.  相似文献   

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Dicranopteron Schmitz is removed from the Metopininae and three new species are described. All species are represented by females only and come from Odontolermes and Macrotermes nests in the Orient. A key:to species) is provided. One species was observed ovipositing in the abdomens of the young stages of O. takensis.  相似文献   

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