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1.
Phyllagathis tuberculataKing and two closely allied new species,P. magnificaA. Weber andP. stoneiA. Weber, are described and illustrated. Within the genus, these species form a distinct and isolated group which is restricted to Peninsular Malaysia.P. tuberculata occurs in Perak (probably confined to G. Bujang Melaka),P. magnifica andP. stonei are found in the mountains on the Pahang/Selangor border (Genting Highlands, Gombak valley). The distinctive characters of the three species are listed and some general information relating to inflorescence morphology, tubercle anatomy, fruit structure and seed dispersal is provided.  相似文献   

2.
Dynastid scarab beetle pollination appears basic within the genusAnnona. Those species ofAnnona which are more morphologically derived, as well as allRollinia spp. possess reduced floral chambers and attract small beetles likeNitidulidae orStaphylinidae. Pollination of the primitive species ofAnnona byDynastinae would imply that the genus had not evolved before the Tertiary. The fossil record is in congruence with this hypothesis. Once again it is stressed that the cantharophilous syndrome, as it is found in theAnnonaceae, Magnoliaceae, Eupomatiaceae andCalycanthaceae, with beetles being exclusive pollinators, is a secondary and derived condition and obviously different from the expected basic entomophily of the original angiosperms.  相似文献   

3.
Based on personal collections ofGlobba unifoliaRidl. andG. unifolia var.sessilifloraHoltt., the latter is recognized as a distinct species. As the nameG. sessiliflora is already occupied, the nomen novumG. corneri is proposed in honour of Prof. DrE. J. H. Corner, who was the first collector of the plant.Dedicated to Prof. DrE. J. H. Corner (Cambridge) on the occasion of his 85th birthday on January 12th, 1991.  相似文献   

4.
The reproductive biology of Zeyheria montana was studied through field observations of flower visitors and floral events, controlled manual pollinations, and observations of pollen tube growth and ovule penetration by fluorescence microscopy. Analysis of secretory areas of the nectar chamber was made by flower dissections and histology of serial sections. The flower lasted 6–8 days, but pollen exposure and stigma receptivity occurred only up to the end of the first and second days, respectively. Pollination was effected by several species of hummingbirds, especially Colibri serrirostris. The flowers present a rudimentary, non-functional disc, and secretion of nectar is performed by corolla-borne glandular trichomes. Only hand cross-pollinated and natural-pollinated flowers set fruits. Artificially self-pollinated and non-pollinated flowers dried off after anthesis without presenting any swelling of the ovary. Almost all the ovules in selfed and crossed pistils were penetrated 96 h after pollination. However, a delay in ovule penetration in self-pollinated pistils was verified, which indicates the occurrence of late-acting self-incompatibility.We are grateful to Fundo de Apoio ao Ensino e à Pesquisa (UNICAMP) for financial support, and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for the fellowship granted to the first author (this work is part of a Ph.D. thesis presented to UNICAMP, Campinas, SP, Brazil).  相似文献   

5.
Chromosome numbers for six Australian taxa ofEuphrasia have been determined. Improved staining techniques have shown that numbers for four of the taxa published previously by the first author were incorrect. The investigated taxa show high ploidy levels with an apparent base number of x = 11, the same as for the genus outside Australia.Dedicated to Prof. DrElisabeth Tschermak-Woess on the occasion of her 70th birthday.  相似文献   

6.
5 new taxa ofHabenaria, namelyH. bougainvillae, H. elongataR. Br. var.leptophylla, H. ensigera, H. rechingeri andH. trichoglossa, are described and illustrated, with reference to affinities to related Australian and Indo-malayan species. The occurrence in New Guinea of severalHabenaria spp. typical for a savanna-like vegetation, led to look more thoroughly at these taxa:H. elongataR. Br. andH. ochroleucaR. Br., considered so far to be endemic in Northern Australia, andH. khasianaHook. f., hitherto only known from southeastern Asia.Studies in the subtribeHabenariinaeBentham (Orchidaceae), 2.—Part 1: Candollea34, 357 (1979).Dedicated to Hofrat Prof. DrKarl Heinz Rechinger on the occasion of his 80th birthday. — On April 30, in the year 1927, the author and his brotherOtto Renz metKarl Heinz Rechinger on a small steam-boat in a stormy Aegaen Sea, travelling from Piraeus to the Northern Sporades Islands:Karl Heinz with destination to Chelidromia, the author andO. Renz to Skopelos. By this lucky chance a lasting friendship began.  相似文献   

7.
Four types of floral breeding systems—(i) chasmogamy, (ii) aerial pseudocleistogamy, (iii) subterranean pseudocleistogamy and (iv) obligate subterranean true cleistogamy—are observed in the populations ofVigna minima inhabiting the Western Ghats (India). Five categories of phenotypes are recognized based on the number and kinds of floral breeding systems found in a given individual. The frequencies of different categories of phenotypes not only show intra- and interpopulation variation, but also fluctuate from generation to generation suggesting differences in the genetic structure of populations. This polymorphism in the breeding system of a single species is unique and may be adaptive. Obligate subterranean true cleistogamy and amphicarpy appear to be adaptations to jungle fires and soil erosion.—The flowers are of the flag-blossom type and insect visitors act as tripping agents. The tripping mechanism together with the polymorphic floral breeding system result in a balanced mixture of selfing and outcrossing. Such a recombination system may enhance the fitness ofV. minima which is essentially a colonizing species.  相似文献   

8.
Leporella fimbriata is a self compatible orchid of southern Australia. It is dependant across its range on unique pollination by sexually attracted male winged antsMyrmecia urens, which pseudocopulate with the flower. Typical pollination sequences began with an initial circling then zig-zag flight to the flower. Vectors usually alighted on the inflorescence stem and quickly crawled to the flower where they adopted a copulatory position sideways along the wide labellum, pseudocopulatory probing immediately followed. In this position pollen carried on the thorax was deposited on the stigma. Departure from the labellum usually resulted in pollinium removal. Pollinator movements were restricted and the distribution leptokurtic with a mean of 3.141 ± 4.59 m. Pollination was widespread but variable from site to site and season to season with a maximum of 70% of all flowers being pollinated. Pollinator limitation is indicated. Traits essential for this pollination interaction include the coincidence of orchid and ant geographic distributions and the coincidence of flowering with the flight period of the ant. The production of pheromonelike substances and the distinctive floral morphology are also essential for attraction and manipulation of male ants. The ant mating system which the orchid can exploit is also important.  相似文献   

9.
Four new species of the generaBeaufortia, Chamaelaucium, Drosera, andPultenaea are described based on the author's collections from SW. Australia. Their affinities are discussed and full illustrations are provided.Dedicated to Hofrat Univ.-Prof.K. H. Rechinger on the occasion of his 80th birthday.  相似文献   

10.
The primary pollinator of Polynesian heliconias,Heliconia laufao andH. paka, is the Wattled Honeyeater,Foulehaio carunculata. This report is the first documentation of pollination by honeyeaters in the genusHeliconia and the first record ofF. carunculata as a pollinator of a plant species. The Polynesian heliconias bear inflorescences that produce 2–4 hermaphroditic flowers per day for a period of 2–3 months. Each flower secretes abundant nectar (125–184 l) with low sugar concentration (15–18% sucrose-equivalents, weight per weight basis) which is available at anthesis just before dawn. Ninety percent of flower visits occur between anthesis and mid-morning. The honeyeaters perch on inflorescence bracts, and probing of the flower results in pollen deposition on the head and bill from where pollen is transferred between flowers. No statements on compatibility can be made forHeliconia paka; however,Heliconia laufao appears to be self-compatible. Calculations of energetic values of nectar of the Polynesian heliconias and Daily Energy Expenditures ofF. carunculata suggest that populations ofH. laufao andH. paka serve as rich energy resources for their pollinators.  相似文献   

11.
Anthecological observations of an orchidBletilla striata were carried out in Kobe, Japan. The purplish pink flowers were visited by 26 species of insects belonging to Hymenoptera, Diptera and Lepidoptera, although the flower did not offer food rewards of any kind. Candidates for pollination were seven species of aculeate Hymenoptera with a body size that well fitted the space in between the column and labellum. The most effective candidate was the male of the longhorn beeTetralonia nipponensis, judging from its abundance and legitimate intrafloral behavior. The female ofT. nipponensis and the other six species also contributed to promote out-crossing, but to a lesser extent than the maleT. nipponensis, since they occasionally exhibited illegitimate intrafloral behaviors for pollination and also, their flower visitation rate was lower.  相似文献   

12.
The exines of pollen grains ofHibbertia stricta (DC.)R. Br. exF. Muell. (Sect.Pleurandra) wear an oily, yellow pollen coat that stains positively for lipids. The pollen is collected by asocial bees, exclusively. The most common floral foragers are members of the genusLasioglossum (subgenusChilalictus;Halictidae) and they harvest pollen via thoracic vibration. As these bees cling to the inflated anthers their pollen smeared bodies come in contact with either of the two wet, nonpapillate stigmas. The stigmas respond positively to cytochemical tests for the presence of esterase immediately following expansion of the corolla, indicating the effective pollination period. The foraging patterns of the bees are narrowly to broadly polylectic. AsH. stricta flowers are nectarless, it is not surprising that bees bearing mixed pollen loads always carry the pollen of at least one nectariferous, coblooming plant. The pollination biology ofH. stricta is compared with otherHibbertia spp. and with pollen flowers in general.  相似文献   

13.
Dynastid scarab beetles are the main or exclusive pollinators ofAnnona spp. with large flowers and wide floral chambers. These nocturnal beetles are attracted by the characteristic odours which are caused by measurable temperature elevation of the flowers up to 10°C or even 15°C above the ambient air temperature. TheAnnona spp. investigated showed different floral rhythms varying from one to three days. The elaborate and wellcoordinated flowering processes, along with floral heating and olfactorial attraction of the night-activeCyclocephala spp., result in a very precise and effective pollination. The floral chamber provides alimentation for the beetles in the form of nutritious food-tissues and pollen and offers a mating place and a well developed shelter against predation and environmental changes. A staggered flowering period and an alternative attraction of different beetle species seems to be more a device for diminishing competition between the cooccurringAnnona spp. than a hybridization barrier.  相似文献   

14.
Three co-existing pollination mechanisms are found inUrginea maritima: insect-, wind-, and self-pollination. The flowers exhibit a typical insect-pollination syndrome; they offer abundant exposed nectar as well as pollen. Out of the many different visitors only a few could be regarded as pollinators:Apis mellifera, Polistes gallicus, andVespa orientalis. Wind pollination also occurs and generally is responsible for self-pollination.It is argued that the development of extra wind-pollination accompanied by partial self-incompatibility is an adaptation to increase pollination in an unfavourable season (August–September), when insects are scarce.  相似文献   

15.
Heterostyly is clearly confirmed inAconogonon campanulatum. This distylous species is dimorphic for tepals, styles, stigma surface, stamens, pollen grain size, and pollen sexine ornamentation. The floral shape is campanulate and thrum flowers are slightly larger than pin flowers. Small solitary bees were observed as flower visitors and probably effected pollination. The possible evolution of dioecy via heterostyly within the genusAconogonon is discussed.  相似文献   

16.
Summary The genus Pandorea, family Bignoniaceae, occurs naturally in Australia. Pandorea pandorana and P. jasminoides were used in intraspecific diallel crosses in order to test for the presence of self-incompatibility and the effect of genotype. Both species were found to be highly self-incompatible. Only 2 out of 353 (0.6%) selfpollinations compared to 337 out of 485 (69.5%) of outcross-pollinations of P. pandorana set fruit. Similarly, for P. jasminoides, 4 out of 235 (1.7%) self-pollinations and 175 out of 296 (59.1%) of outcross pollinations set fruit. Both reciprocal and genotype effects were found in P. pandorana. Fruit-set differences occurred between two different genotypes of P. jasminoides, but reciprocal effects were not found. Data were analysed using generalized linear models with a logit-link function assuming a binomial error distribution. The relative merits of the various models are discussed.  相似文献   

17.
Individual flowers ofMoraea inclinata are nectariferous and last about six hours. They appear to be pollinated largely by bees in the familyHalictidae (Lasioglossum spp.,Nomia spp.,Zonalictus) and to a lesser extent by bees in the familyAnthophoridae (Amegilla). The mechanism of bee-pollination inM. inclinata is the Iris type; i.e., each flower consists of three pollination units (an outer tepal, a partly exserted anther, and the opposed style branch which terminates in a pair of petal-like crests). Bees rarely visit more than one pollination unit per flower. Transferral of pollen to the bee is passive and nototribic although all bees collected on the flowers were female and 55% of the bees carried pollen loads with 2–5 pollen taxa in their scopae.Moraea brevistyla flowers are nectariferous but lack scent and last two days. They are visited infrequently by bees and only one femaleLasioglossum spec. carried the pollen ofM. brevistyla. Unlike flowers ofM. inclinata those ofM. brevistyla deposit pollen only on the head and thorax. Bee-mediated autogamy in both species is avoided due to the erratic foraging patterns of the bees and the flexibility of each stigma lobe as the bee backs out of the flower. Approximately 2–4 flowers in the inflorescences of both species (6–8 flowers/infloresence) develop into capsules.  相似文献   

18.
Morphological and molecular comparisons were made forCampsis grandiflora (Thunb.)K. Schumann (Bignoniaceae) from eastern Asia andC. radicans (L.)Seemann from eastern North America. Chloroplast DNA (cpDNA) variation was surveyed with 20 restriction endonucleases. The cpDNA divergence between the two vicariad species was 2.44%, which is the highest reported among North Temperate disjunct taxa and one of the highest reported for infrageneric taxa. Detailed morphological comparisons also suggest a high level of divergence. Cluster analyses based on 22 morphological characters and 39 OTUs revealed two distinct groups corresponding with the two species. The average taxonomic distance between the two species was 1.806. Analyses of variance (ANOVA) revealed that 12 of the 18 quantitative characters differed significantly ( 0.01) betweenC. grandiflora andC. radicans. Divergence time based on cpDNA data was estimated as 24.4 million years. The Bering land bridge hypothesis was favored over the North Atlantic land bridge hypothesis based on the estimated divergence time and the geological history of the North Temperate region. The high levels of morphological and cpDNA divergence are not consistent with morphological stasis, which has been proposed as a common mode of evolution for North Temperate disjunct taxa.  相似文献   

19.
The subfamilyPhytelephantoideae comprises three genera (Ammandra, Aphandra, andPhytelephas) and seven species of dioecious palms. The floral scents ofAmmandra dasyneura, A. decasperma, Aphandra natalia, Phytelephas aequatorialis, P. macrocarpa, andP. seemannii were analyzed by gas chromatography-mass spectrometry. We studied the pollination biology ofA. natalia, P. aequatorialis, andP. macrocarpa, and tested how the synthetically produced main constituents of the floral scents ofAphandra andPhytelephas attracted insects in two natural populations ofPhytelephas. The genera are distinct in terms of floral scents.Ammandra has sesquiterpenes,Aphandra (+)-2-methoxy-3-sec-butylpyrazine, andPhytelephas p-methyl anisol. These constituents dominated the scents quantitatively and qualitatively. The similarity between scents of male and female inflorescences was 76.5% inAmmandra, 84.2% inAphandra, and >99% inPhytelephas. Different species ofAleocharinae (Staphylinidae) pollinateAphandra natalia andPhytelephas species and reproduce in their male inflorescences.Derelomini (Curculinoidae) andMystrops (Nitidulidae) only visit and pollinatePhytelephas in which male inflorescences they reproduce. A species ofBaridinae (Curculionidae) only visits and pollinatesAphandra natalia, and reproduces in its female inflorescence. The apparent reliance on one or a few floral scent constituents as attractants and few and specific pollinators may indicate co-evolution. Sympatric species ofPhytelephantoideae have different scents. We suggest that species with similar scents have allopatric distributions due to the absence of a pollinator isolation mechanism.  相似文献   

20.
Stefan Andersson 《Oecologia》1988,76(1):125-130
Summary Bumblebees foraging on the self-incompatible Anchusa officinalis fly between near neighbour plants and between near neighbour inflorescences within plants. Although many-flowered plants attracted most bumblebees these plants received fewer visits on a per flower basis than smaller plants, and each bumblebee visited a smaller proportion of the flowers. The calculated effective visitation rate per flower was highest on plants of an intermediate size. If pollen-carryover was assumed to be limited the most efficient plant was predicted to be smaller since the proportion of fertilized flowers per bumblebee visit is expected to decrease further on the largest plants in relation to the total flower number. These predictions were tested by measuring fruit-set in the field. The percentage fruit-set decreased with plant size at all sizes that were investigated. That the most efficient plant was small indicates that pollen-carryover was indeed limited. However, the low percentage fruit-set associated with large size did not present a serious problem since the total estimated seed production per plant still increased with size. Selection favoring smaller plants may be low or absent in Anchusa.  相似文献   

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