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1.
We report the relative abundance of inflorescence tissue feeders among three willow species (Salix integra, S. miyabeana and S. sachalinensis) with reference to the plant sexes. We found that (i) a total of 270 individuals belonging to six species and two orders were recorded from willow inflorescences; (ii) the abundance of Xanthia caterpillars differed across willow species and sexes; (iii) the abundance of weevil larvae differed across willow species; (iv) Gypsonoma bifasciata abundance was affected by sex and inflorescence size; and (v) Nemophora raddei was collected from a single female S. miyabeana tree. Although nitrogen content of inflorescences is not likely to affect the herbivory pattern of inflorescence tissue feeders, inflorescence size is likely to affect the abundance of Gypsonoma caterpillars.  相似文献   

2.
Ainsliaea asaroides Y. S. Ye, Jun Wang & H. G. Ye (Asteraceae), a new species from Guangdong, China, is described and illustrated. The new species resembles A. gracilis Franch. but can be distinguished by its sub‐leathery, cordate leaves, villose petiole, thyrsoid inflorescence and the number of florets. A key to allied species is provided.  相似文献   

3.
Two new species of Sloanea are described and illustrated: S. fasciculata D. Samp. & V. C. Souza and S. hatschbachii D. Samp. & V. C. Souza. Both species are endemic to the Atlantic Forest states of Espírito Santo and Paraná in Brazil. S. fasciculata is similar to S. hirsuta (Schott) Planch. ex Benth., but has a fasciculate inflorescence and deeply-divided stigma. S. hatschbachii is similar to S. lasiocoma K. Schum. with regard to the morphology of the leaves, flowers and inflorescence, which is a frondose-bracteate raceme, but can be differentiated by the size of the style, the extension of the connective, and the length of the sepals.  相似文献   

4.
5.
A new species of the genus Colocasiomyia de Meijere (Diptera: Drosophilidae) was discovered from inflorescences of Steudnera colocasiifolia K. Koch (Araceae) in Yunnan, China. The new species is described as Colocasiomyia steudnerae Takenaka and Toda, sp. nov., and we investigated the reproductive ecology of both the fly and the plant species. This fly species reproduces in the inflorescences/infructescences of the plant, and depends almost throughout its entire life cycle on the host plant. The fly species is the most abundant flower visitor for S. colocasiifolia and behaves intimately with the flowering events, suggesting that it is the unique and most efficient pollinator for the host plant. Bagging (insect‐exclusion) treatment of inflorescences resulted in no fruits. These findings strongly suggest that intimate pollination mutualism has evolved between the fly and the host plant, as are known in other Colocasiomyia flies and Araceae plants. One notable feature of this system is that the new species almost monopolizes the host‐plant inflorescence as a visitor, without any cohabiting Colocasiomyia species. In comparison to other cases where two Colocasiomyia species share the same inflorescence and infructescence of Araceae host plants for reproduction by separating their breeding niches microallopatrically between the staminate (upper male‐flower) and the pistillate (lower female‐flower) regions on the spadix, C. steudnerae exhibits a mixture of stamenicolous and pistillicolous breeding habits.  相似文献   

6.
A new species, Leucas pachmarhiensis (Lamiaceae), is described and illustrated from the Pachmarhi Biosphere Reserve, Hoshangabad district, Madhya Pradesh, India with conservation status assessed as ‘Critically Endangered’. This novelity is endemic to central India and belongs to Leucas sect. Plagiostoma. It differs from other species of this section by its height up to 120 cm, and inflorescence positioned at multiple nodes. Detailed notes on its conservation status and ecology are provided.  相似文献   

7.
John J. Pipoly 《Brittonia》1999,51(2):128-133
Herbarium studies leading to a treatment of the Myrsinaceae for the Flora of Central French Guiana resulted in the discovery of two heretofore undescribed species,Cybianthus prevostiae andStylogyne incognita. The species are described and illustrated, and hypotheses regarding phylogenetic relationships with their respective congeners are provided.Cybianthus prevostiae is unusual among members ofCybianthus subgen.Weigeltia owing to its monoaxial habit and ellipsoid pistil, and deeply cupuliform calyx.Stylogyne incognita, a taxon often confused withS. micrantha, is most closely related toS. sordida but is separated from it by the corymbose inflorescence, entire leaves, longer petioles, and membranaceous perianth.  相似文献   

8.
Svaťa M. Louda 《Oecologia》1982,55(2):185-191
Summary Predators on flower visitors, such as spiders, could influence plant reproduction by determining the balance between pollination and seed predation by insects. This study examines the net effect of predation by the inflorescence spider, Peucetia viridans (Hentz), for seed production by a native plant species on which it hunts. Both pollination and seed set of Haplopappus venetus (Asteraceae) were reduced on branches with spiders; however, the release of viable, undamaged seed was higher on inflorescence branches with spiders than on those without. Occurrence of P. viridans was associated with the flat-topped inflorescence branch structure characteristic of H. venetus rather than with the vertical structure of its congener, H. squarrosus. Thus, the interaction should be a reinforcing selective pressure on inflorescence branch morphology of H. venetus over time. Two factors providing constraints on the degree and rate of coevolution of the plant-spider interaction are suggested by the results: (1) the critical role of phenological synchrony and (2) the opposing requirements of interacting species and of subsequent life history stages within a species.  相似文献   

9.
Eriogonum soliceps, a new species of subg.Eucycla sect.Capitata, is described. It may be readily distinguished from all other taxa of the subgenus by its reduced inflorescence. From its presumed nearest relative,E. mancum, this new species differs in its solitary (vs. 2–5) involucre, presence of a peduncle but no scape, lack of bracts at the base of the involucre, and distinctly pustulose midribs of the mature flowers.  相似文献   

10.
Derris gamblei (Fabaceae), is described and illustrated as a new species from the Pudukkottai district of Tamil Nadu state, India. It resembles the Indian species Derris thothathrii, but differs by its short inflorescence, pseudoracemes, pubescence at dorsal apex of all petals, 2 ovules and narrow‐winged pods.  相似文献   

11.
Clusia blattophila (Clusiaceae) is described as a new species. It is distinguished from related species in C. sect. Oedematopus by e.g. the relatively large and reflexed petals and from other Clusia spp. by having fewer (6–16) stamens and only four petals. Unique traits are the almost sessile inflorescence and the presence of a secretory pit at the floral apex in staminate flowers. The species grows epilithically and is known only from the Nouragues inselberg, a massive granite outcrop in eastern French Guiana. The name refers to its cockroach pollinators.  相似文献   

12.
A species of Sartidia De Winter, first collected by P.J. Muller in 1972 in the Cythna Letty Nature Reserve in Mpumalanga, does not match existing material of Sartidia, a genus comprising four species. The new species, S. dewinteri J. Munday & L. Fish, is most similar to S. jucunda (Schweick.) De Winter but differs in the leaf sheath colour, lower leaf blade surface texture, spikelet length and upper glume length. It differs also from all other species in the genus in the shape and branching of the inflorescence, the relative length of the lateral awns to the median awn, lemma body surface texture, callus shape and hair arrangement, palea shape and distribution. Sartidia dewinteri differs anatomically from S. angolensis and S. vanderystii in that the stereome strands in the leaf blades project partly or almost completely into the first order vascular bundles rather than not at all, and from S. jucunda by having 3 rather than 5 first order vascular bundles in the leaf. Sartidia dewinteri is known only from ultramafic soils of the Barberton Greenstone Belt and is thus considered a serpentine endemic. The IUCN conservation status of S. dewinteri is considered to be Lower Risk — least concern, although some of its ultramafic habitat is under threat from afforestation and the after effects of mining.  相似文献   

13.
The new species Spiradiclis jingxiensis R. J. Wang is described here. It is similar to S. danxiashanensis with respect to its prostrate habit, small leaves, and terminal inflorescence with 1–3 salverform flowers, but is readily distinguished by pinkish flowers, and included stamens and stigmas in long‐ and short‐styled flowers. The conservation status of the new species was preliminarily assessed as ‘EN’ according to IUCN categories and criteria.  相似文献   

14.
The correlation between pollen-ovule (P/O) ratio and breeding system has generally been analysed with respect either to pollination efficiency, or in terms of sex allocation theory. Pollen/ovule ratios were measured in nine species of Araceae belonging to two genera with bisexual flowers (Anaphyllopsis, Monstera) and three genera with unisexual flowers (Dieffenbachia, Philodendron, Montrichardia). The family Araceae with its unique inflorescence morphology allows the analysis of variations of the P/O ratio with respect to two basal morpho-functional pollination units: the flower or the inflorescence. We found a relationship between the value of the P/O ratio and the breeding system that is partially different from Cruden's results (1977). Some facultative xenogamous species have a higher P/O than the obligatory xenogamous species. A link was found between the P/O and the type of inflorescence, the floral cycle, and the mode of growth.  相似文献   

15.
Strychnos jacarepiensis E. A. Manoel & E. F. Guim. is described and illustrated as a new species from Rio de Janeiro state, Brazil. It differs from S. gardneri by the terminal inflorescence and shorter corolla tube, and from S. brasiliensis by the connate and amplexicaul interpetiolar stipule, velutinous calyx lobes, villous filaments and discoid seeds.  相似文献   

16.
Traditionally, annual colonising species are expected to have high rates of self‐fertilisation, although recent theoretical and empirical studies have shown that cross‐fertilisation can be selected for under heterogeneous pollination environments. Solanum rostratum is a self‐compatible annual herb that colonises disturbed habitats. Despite the lack of physiological mechanisms to prevent self‐fertilisation, pollen transfer between individuals is expected to be favoured because of its complex floral morphology. In previous studies of S. rostratum it has been shown that anther dimorphism within flowers results in precise pollen placement on the pollinator's body, and the presence of mirror‐image floral morphs within plants promotes outcrossing in experimental arrays. However, the mating system of natural populations of S. rostratum has never been assessed, and thus whether it is predominantly selfing or outcrossing remains unknown. We hypothesise that floral and inflorescence morphology of S. rostratum should facilitate cross‐fertilisation, making it a predominantly outcrossing despite its lack of a self‐incompatibility system. To test this hypothesis, we estimated outcrossing rates by genotyping 700 individuals at 13 microsatellite loci, sampled from four populations across a 690‐km transect in the species' native range. We found that populations had mean outcrossing rates of 0.70 ± 0.03, with multiple sires contributing to paternity of each progeny array (average effective number of sires = 8.97 ± 0.57). This indicates that natural populations S. rostratum have relatively high levels of outcrossing, probably facilitated by its floral and inflorescence morphology. We speculate that partial selfing in this species may be an unavoidable consequence of displaying multiple flowers at the same time (geitonogamy), as well as the result of self‐pollen transfer by illegitimate visitors.  相似文献   

17.
报道了姜科(Zingiberaceae)凹唇姜属(Boesenbergia Kuntze)1个中国新记录植物:广义凹唇姜(B.quangngaiensis N.S.Lý),其叶背绿色,被白霜,穗状花序顶生,花交替排列成2列,偏生于花序同一侧,唇瓣近圆形或宽倒卵形,基部中间具深红色带,顶端中部具紫红色斑点,可与同属其他种区别。提供了该植物的形态描述、彩色图片及中国凹唇姜属分种检索表。  相似文献   

18.
Daphne thanguensis sp. nov. from north Sikkim of eastern Himalaya is described and illustrated. It is a narrow endemic related to D. tangutica Maxim. Daphne thanguensis grows in open alpine pastures and differs from D. tangutica by having leaves with revolute margin and a tuft of hairs at apex, ebracteate inflorescence and flowers, calyx lobes with a tuft of hairs at apex and annular, slightly undulate hypogynal disk. The new taxon is also close to D. retusa Hemsl. But can easily be differentiated by its sessile inflorescence, ebracteate flowers and tuft of hairs at leaf apices and calyx lobe apices. A conservation status of the new species in accordance with the IUCN red list categories and criteria is provided and discussed.  相似文献   

19.
In order to find out if the inflorescences number variation has influences on the gender modification in plant species, we investigated the gender modification in a cultivated population of the monoecious species Sagittaria potamogetifolia. We also designed two nutrient levels to explore the impact of nutrient on gender modification in S. potamogetifolia. We found that the female and male flowers did not change with increasing plant size for each inflorescence at a low nutrient level. At a high nutrient level, the female flower numbers on each inflorescence did not increase with plant size; however, the male flower numbers had some positive correlation with the plant size. At the ramet level, the total male and female flower numbers increased with the plant size at both nutrient levels. The sex ratio (female to male flower ratio) decreased with the inflorescence numbers and the plant size (Midvein length). Although the nutrient variation had impact on the flower number production, it did not change the gender modification pattern. The high plasticity of inflorescence numbers, which caused the gender variation in S. potamogetifolia, and low plasticity of female and male flowers on a single inflorescence, indicates that the limited modification on gender in a single inflorescence may be compensated by inflorescence number variation at the ramet level.  相似文献   

20.
A total of 21 Colocasiomyia species, including 17 undescribed species, are reported from Sabah (Mt. Kinabalu and neighboring areas), Malaysia, based on samples collected from inflorescences of 14 or 15 Araceae species. This number of species is the largest as a local fauna of this genus in the world. The high species diversity is attributed to 12 undescribed species belonging to the Colocasiomyia baechlii species group. A particular breeding habit of Colocasiomyia is sharing of the same inflorescence by a pair of species, with partial niche separation between them: one species uses exclusively the pistillate (lower female‐flower) section of the spadix for oviposition and larval development, whereas the other mostly uses the staminate (upper male‐flower) section. However, the baechlii group species show quite different patterns of host plant use: many (up to eight) species cohabit on the same inflorescence. It is unlikely that they separate their breeding niches micro‐allopatrically within an inflorescence. Instead, species composition and their proportions of individual numbers vary among different localities, seasons and host plants, with partial overlap among them. Such partial separations in local distribution, phenology and host selection would in combination contribute to their coexistence and promote the species diversity of this group.  相似文献   

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