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1.
Three new species, Hiptage calcicola, H. gracilis , and H. monopteryx are described. A key to the species of Hiptage found in Thailand is provided.  相似文献   

2.
亚洲特有植物风筝果(Hiptage benghalensis)镜像花(mirror-image flowers)的雌雄异位变化极大, 柱头与可育花药的空间距离在海南岛与云南西双版纳种群仅有2-4 mm, 而在贵州及云南东南部种群可达10-12 mm。为验证 “镜像花雌雄异位的变化是各个地理种群受到传粉昆虫体型大小选择的结果”假说, 本文开展了传粉生态学与分子生物学研究, 探讨风筝果不同地理种群的雌雄异位变化是否与当地传粉者体型相关, 是否有着遗传基础, 以及是否形成了“传粉生态型”(pollination ecotype)。结果表明, 雌雄异位程度大的贵州种群和云南东南部种群, 其传粉者也是体型较大的木蜂(Xylocopa nasalis)和熊蜂一种(Bombus sp.); 雌雄异位程度小的海南岛种群和云南西双版纳种群的传粉者则是体型较小的大蜜蜂(Apis dorsata)、西方蜜蜂(A. mellifera)。除了雌雄异位的明显分化(F = 53.69, P < 0.01)之外, 花柱长度也在这两类种群之间差异显著(F = 12.5, P < 0.05), 与传粉昆虫身体长度密切相关。通过叶绿体ycf1b、rbcL和细胞核ITS 3个DNA片段的序列分析, 由大型蜂传粉的雌雄异位程度较大的3个种群(贵州和云南东南部种群)遗传关系极近, 与小型蜂传粉种群(雌雄异位较小的海南岛种群和云南西双版纳种群)存在明显的遗传分化。这些结果显示, 风筝果不同地理种群的镜像花雌雄异位程度的变化可能是适应局域不同体型大小的传粉昆虫的选择结果, 而且种群间出现了基因流的隔断, 可能与大型蜂、小型蜂传粉的两种生态型有关。镜像花通过雌雄异位的变化适应不同地域的传粉者而形成传粉生态型, 这种传粉生态型及其传粉隔离机制可能是风筝果属物种形成与维持的一个重要原因。  相似文献   

3.
Hiptage lushuiensis, a new species from the Hengduan Mountains, northwestern Yunnan Province, China, is described and illustrated here. This species was found growing at the margin of an open forest in the Nujiang Gorge of Lushui City. Hiptage lushuiensis is distinctive for its pink petals, 2 or more calyx glands, and large and pink samara with white hairs. This species is isolated in the deep gorge (25°51′N, 98°51′E, altitude 917 m), at the northern edge distribution range of the genus. These distinctive morphological differences and the geographic isolation suggest a history of long-distance dispersal and allopatric speciation. Hiptage lushuiensis has a shorter filament but larger herkogamy than related species, suggesting that H. lushuiensis may have adapted to other pollinators with short but fat body such as Amegilla or Bombus spp.  相似文献   

4.
Habitat fragmentation may affect the reproductive success of plant populations in many different ways. Thus, negative, neutral, or positive plant responses can be observed, according to the balance of the different interactions. Variables related to mutualistic and antagonistic interactions (pollinator activity and gall occurrence, respectively) were measured on Byrsonima sericea populations of a fragmented seashore area ( restinga ) in southeastern Brazil. Pollinator visits to the oil-bearing flowers, insect gall occurrence on stems and inflorescences, and fruit set of B. sericea were compared between three small (up to 0.3 ha) and three large (14.0–99.0 ha) fragments. MANOVA showed differences between fragment classes. Nevertheless, a posteriori univariate ANOVA showed that the pollinator visit frequency was more than twofold higher in small fragments, and that gall occurrence and fruit set did not show significant differences between small and large fragments. These results suggest that the habitat fragmentation does not affect the female reproductive success of B. sericea in the studied restinga areas because resource availability seems to be a more important factor for fruit set than pollen limitation due to pollination failure. This is the first work assessing the effects of habitat fragmentation in restinga areas, which are intensely impacted by urbanization, so that no generalization about the fragmentation consequences can still be made for this ecosystem.  相似文献   

5.
Leaf glands of Diplopterys pubipetala were studied with light and electron microscopy. Aspects of their secretion, visitors and phenology were also recorded. Glands occur along the margin, at the apex and at the base of the leaf blade. All the glands begin secretion when the leaf is still very young, and secretion continues during leaf expansion. The highest proportion of young leaves coincides with the beginning of flowering. The glucose‐rich secretion is collected by Camponotus ants, which patrol the newly formed vegetative and reproductive branches. All the glands are sessile, partially set into the mesophyll, and present uniseriate epidermis subtended by nonvascularised parenchyma. The glands at the apex and base are larger and also consist of vascularised subjacent parenchyma. The cytoplasm of epidermal and parenchyma cells has abundant mitochondria, polymorphic plastids filled with oil droplets and a few starch grains. Golgi bodies and endoplasmic reticulum are more abundant in the epidermal cells. The parenchyma cells of the subjacent region contain chloroplasts and large vacuoles. Plasmodesmata connect all the nectary cells. The zinc iodide–osmium tetroxide (ZIO) method revealed differences in the population of organelles between epidermal cells, as well as between epidermal cells and parenchyma cells. Ultrastructural results indicate that leaf glands of Dpubipetala can be classified as mixed secretory glands. However, the secretion released by these glands is basically hydrophilic and composed primarily of sugars, hence these glands function as nectaries.  相似文献   

6.
The present study describes the anatomical structure of calyx and leaf glands in Galphimia brasiliensis and analyzes the mechanism of secretion. The glands are marginal and suprabasal, cup-shaped, sessile, and scarcely visible with the naked eye. Light microscopy reveals the following features: a thin, smooth cuticle; unistratified secretory cells; subglandular parenchyma; and vascular bundle supply composed of phloem and xylem with abundant druses of calcium oxalate. Transmission electron microscopy reveals the presence of secretory cells with conspicuous nuclei, dense cytoplasm, lipid droplets, numerous vesicles, mitochondria, Golgi, rough endoplasmic reticulum (RER), and elongated plastids with osmiophilic contents. The secretion reaches the apoplastic space and accumulates beneath the cuticle. Finally, the viscous, translucent exudate is eliminated by mechanical rupture of the cuticle. Histochemical analysis confirms that lipids are the main constituent. Small amounts of polysaccharides were also identified.  相似文献   

7.
Galls are anomalies in plant development from parasitic origin, and affect cellular differentiation or growth of plants. This parasite–plant interaction occurs in many environments and typically in vegetative organs of plants. The existence of galls in reproductive organs and their effects on the host plant are seldom described in the literature. In this paper, we present a novel study of galls in plants of the neotropical region. Galls of Bruggmmaniella byrsonimae develop in the flower buds of Byrsonima sericea DC. (Malpighiaceae) and affect development of the reproductive organs and the reproductive effort of these plants. The sepals and petals show hypertrophy of parenchyma tissues after differentiation, and the stamens exhibit degeneration of the sporogenic tissue. The gynoecium is not entirely developed; ovary and ovules are often absent. Changes in vascular tissues are also frequent, which may indicate high demand for nutrient resources by the new tissues initiated by the larva. We compared the amount of inflorescences, galls and fruits to evaluate possible effects on host reproduction. The results suggest that the Cecidomyiidae galls in flower organs affect fruit set and the reproductive success of B. sericea.  相似文献   

8.
Seven new species ofMascagnia are described:M. tomentosa from southern Mexico and Central America;M. arenicola from the Guianas;M. riparia, M. tucuruensis, andM. velutina from Brazil;M. boliviana from Bolivia; andM. australis from Argentina and Paraguay. These novelties were previously included in the “M. sepium-complex,” an omniumgatherum comprising superficially similar yellow-flowered taxa.  相似文献   

9.
The granular glands of nine species of dendrobatid frogs were examined using light and electron microscopy. The glands are surrounded by a discontinuous layer of smooth muscle cells. Within the glands proper the secretory cells form a true syncytium. Multiple flattened nuclei lie at the periphery of the gland. The peripheral cytoplasm also contains mitochondria, rough surfaced endoplasmic reticulum, the Golgi apparatus, and an abundance of smooth endoplasmic reticulum. Centrally, most of the gland is filled with membrane-bound granules surrounded by amorphous cytoplasm. Few other organelles are found in this region. Early in the secretory cycle, the central part of the gland is filled with flocculent material which appears to be progressively partitioned off by membranes to form the droplet anlage. As granules form, the structure of the contents becomes progressively more vesicular. Dense vesicles, which bud off from the Golgi apparatus, fuse with the granular membrane during the development of granules, and might contain enzymes involved in toxin synthesis. The granules at this point resemble multivesicular bodies. Their structure is similar in all species of dendrobatid frogs even though the different frogs secrete substances of different chemical structure and toxicity.  相似文献   

10.
Galls are anomalies in plant development of parasitic origin that affect the cellular differentiation or growth and represent a remarkable plant–parasite interaction. Byrsonima sericea DC. (Malpighiaceae) is a super host of several different types of gall in both vegetative and reproductive organs. The existence of galls in reproductive organs and their effects on the host plant are seldom described in the literature. In this paper, we present a novel study of galls in plants of the Neotropical region: the ‘witches' broom’ galls developed in floral structures of B. sericea. The unaffected inflorescences are characterised by a single indeterminate main axis with spirally arranged flower buds. The flower buds developed five unaffected brownish hairy sepals and five pairs of elliptical yellow elaiophores, five yellow fringed petals, 10 stamens and a pistil with superior tricarpellar and trilocular ovary. The affected inflorescences showed changes in architecture, with branches arising from the main axis and flower buds. The flower buds exhibited several morphological and anatomical changes. The sepals, petals and carpels converted into leaf‐like structures after differentiation. Stamens exhibited degeneration of the sporogenous tissue and structures containing hyphae and spores. The gynoecium did not develop, forming a central meristematic region, from which emerges the new inflorescence. In this work, we discuss the several changes in development of reproductive structures caused by witches' broom galls and their effects on reproductive success of the host plants.  相似文献   

11.
Madagasikaria andersonii is described here as a new genus and species of Malpighiaceae from Madagascar. The phylogenetic placement of Madagasikaria was estimated by using combined data from ndhF and trnL-F chloroplast sequences and phytochrome (PHYC) and ITS nuclear sequences. It forms a strongly supported clade with the Malagasy endemic genera Rhynchophora and Microsteira. Despite nearly identical floral morphology among species in this clade (here called the madagasikarioid clade), these genera are easily distinguishable on the basis of their fruits. The schizocarpic fruits of Madagasikaria have distinctive mericarps. Each mericarp has a lateral wing, which completely encircles the nut, and a peculiar dorsal wing, which folds over on itself. The morphology of this fruit suggests that the homology of the unusual wing in Rhynchophora is lateral in nature and represents a reduced wing similar to the lateral wing in Madagasikaria. Taxa in the madagasikarioid clade all appear to be morphologically androdioecious and functionally dioecious, producing both staminate and "bisexual" (i.e., functionally carpellate) individuals. This condition appears to be exceedingly rare in flowering plants and has important implications for floral evolution within Malpighiaceae. Neotropical Malpighiaceae are pollinated by specialized oil-collecting anthophorine bees of the tribe Centridini and exhibit highly conserved floral morphology despite tremendous diversity in fruit morphology and habit. These oil-collecting bees are absent from the paleotropics, where most members of the Malpighiaceae lack both the oil glands and the typical floral orientation crucial to pollination by neotropical oil-collecting bees. The madagasikarioids represent one shift from the neotropical pollination syndrome among Old World Malpighiaceae.  相似文献   

12.
Walter H. Lewis 《Brittonia》1973,25(3):304-306
Byrsonima dressleri is newly described as endemic to the low cloud forests of Panama adjacent to the Canal Zone. Its closest relationship appears to be with those taxa of the Guayana Highland and Amazonia.  相似文献   

13.
? Premise of the study: We developed and characterized microsatellite markers for Byrsonima crassifolia (Malpighiaceae), a widely distributed neotropical fruit tree. ? Methods and Results: Eight polymorphic and two monomorphic microsatellite loci were identified and screened in 60 samples from four geographically disparate populations (Bolivia, Brazil, Mexico, and Panama). Each locus exhibited between two and 11 alleles. Expected heterozygosity ranged from 0 to 0.839. All loci amplify in the congeners B. variabilis and B. basiloba, four amplify in B. bucidaefolia, and seven amplify in B. variabilis, although levels of polymorphism have not been assessed. ? Conclusions: These loci will provide novel tools for comparing genetic diversity present in cultivated and noncultivated populations of B. crassifolia throughout its range, and may prove valuable in related species.  相似文献   

14.
Camarea is a South-American endemic genus comprising eight species. In the present work leaf flavonoids of seven species of Camarea were identified, aiming to evaluate the usefulness of their distribution as a taxonomic aid. A total of 12 flavonoids were isolated and identified. Free aglycones, such as apigenin, chrysoeriol, kaempferol and quercetin, as well as 7-O-glycosides of apigenin and luteolin, 3-O-glycosides of kaempferol and quercetin were identified. Flavonoid distribution in Camarea species, taking into account aglycones and aglycone moieties of glycosides, was used to obtain a phenogram of chemical affinities. Apigenin, chrysoeriol and kaempferol were the main discriminating characters for links establishment. The resultant tree suggests the links: 1) Camarea hirsuta, Camarea affinis and C. affinis × C. hirsuta; 2) Camarea elongata and Camarea axillaris; 3) Camarea sericea and Camarea humifusa. The results are in agreement with morphological similarities and disagree with several points of n-alkane evidence. The results support the recognition of Camarea triphylla as synonymy of C. axillaris.  相似文献   

15.
Pterandra sericea, a new species from southeastern Venezuela and western Guyana, is described, illustrated, and compared with its nearest relative,P. flavescens, another species of the Guayana Highland.  相似文献   

16.
Bronwen Gates 《Brittonia》1979,31(1):108-109
Three new combinations are made and three new species are described; all are Malpighiaceae.  相似文献   

17.
18.
Summary This study indictes the complexity of cell function in one tissue. Cells of the larval salivary gland produce their secretion both by synthesis of some proteins and extraction of different proteins from the hemolymph by selective uptake and concentration. Uptake and transport are not dependent on de novo protein synthesis, at least for several hours and, as would be expected, are also not immediately dependent on new RNA synthesis. De novo synthesis of secretory proteins by the gland is almost completely inhibited by puromycin but occurs on RNA templates which are stable for at least 12 hr. Both the large cells forming most of the gland and the smaller cells forming the duct and the base of the duct are capable of taking up hemal, proteins, but synthesis of secretory proteins probably occurs only in the large cells.  相似文献   

19.
Four new Passalora species were found on leaves of Cerrado native plants of the genus Peixotoa (Malpighiaceae). Two of the new Passalora species (P. peixotae-reticulatae and P. cerradensis) belong in Section Mycovellosiella, while P. peixotoae-goianae and P.brasilianensis belong in Section Phaeoramularia.  相似文献   

20.
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