Sexual Dimorphism in Catasetum Orchids: Forcible Pollen Emplacement and Male Flower Competition

@article{Romero1986SexualDI,
  title={Sexual Dimorphism in Catasetum Orchids: Forcible Pollen Emplacement and Male Flower Competition},
  author={Gustavo As Romero and Charles Edward Nelson},
  journal={Science},
  year={1986},
  volume={232},
  pages={1538 - 1540}
}
Orchids of the Neotropical genus Catasetum have sexually dimorphic flowers; that is, male and female flowers are distinctly different in shape and color. Male flowers forcibly attach a large pollinarium onto euglossine bees. Euglossa bees leave the male flower in response to pollinarium emplacement by Catasetum ochraceum and subsequently avoid male but not female flowers. This evidence suggests that sexual dimorphism promotes pollination. The aversion of the bee to pollinarium attachment and… Expand
Sexual dimorphism in floral scents of the neotropical orchid Catasetum arietinum and its possible ecological and evolutionary significance
TLDR
The influence of sex-specific floral scents on the behaviour of euglossine pollinators is discussed and new insights into the ecological and evolutionary significance of divergence in floral scENTS among dioecious plants are offered. Expand
Non‐functional flowers in Catasetum orchids (Catasetinae, Orchidaceae)
TLDR
The absence of truly hermaphroditic flowers in Catasetum is important in the interpretation of evidence for gender choice in this genus, as flowers and/or plants can be unequivocally scored as either functionally male or female. Expand
Pollination biology in the dioecious orchid Catasetum uncatum: How does floral scent influence the behaviour of pollinators?
TLDR
The rapid loss in the attractiveness of flowers following pollinarium removal/deposition can be interpreted as a strategy to direct pollinators to non-pollinated flowers, and interesting insights into the evolution of floral signals in gender-dimorphic species are provided. Expand
Differential floral rewards and pollination by deceit in unisexual flowers
TLDR
It is suggested that true intersexual floral mimicry can lead to different ecological/ evolutionary consequences than deceit-pollination without specific resemblance and in mimicry systems, sexual dimorphism and intrasexual floral polymorphism are less likely and the dependence on naive pollinators is less strong. Expand
Biology of the Neotropical orchid genus Catasetum: a historical review on floral scent chemistry and pollinators
TLDR
It is hoped this review will stimulate research not only on the ecology and evolution of Catasetum but also of the about 1000 species of fragrance-rewarding plants that are found in the Neotropics. Expand
Gynomonoecy in a mycoheterotrophic orchid Eulophia zollingeri with autonomous selfing hermaphroditic flowers and putatively outcrossing female flowers
TLDR
The present study represents the first documented example of gynomonoecy within Orchidaceae and may be maintained by the tradeoff in reproductive traits between female flowers and hermaphroditic flowers (with high fruit set but inbreeding depression in selfed offspring). Expand
Sexual selection, sexual dimorphism and plant phylogeny
TLDR
It is suggested that the similarity of pattern may be accounted for by a similarity of process within the angiosperms and, indeed, to angiosperm radiation. Expand
Male interference with pollination efficiency in a hermaphroditic orchid
TLDR
Empirical evidence is provided that male interference with pollination efficiency can occur in a hermaphroditic plant and that such interference can compromise fecundity. Expand
La pesadilla de lindley - la biología sexual de catasetum y cycnoches
TLDR
Floral fragrances of five Catasetum species and two Cycnoches species were investigated by gas chromatography and weak differences in the fragrance composition of the separate sexes were detected, begging several questions. Expand
Ecological Correlates of Labile Sex Expression in the Orchid Catasetum Viridiflavum
TLDR
Patterns of sex expression were studied in a natural population of the epi- phytic orchid Catasetum viridiflavum on Barro Colorado Island, Panama, consistent with the hypothesis that sex differences in costs of reproduction in response to changes in substrate (and correlated changes in light availability) may explain the evolution of ESD in C. viridi/lavum. Expand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 15 REFERENCES
POLLINATION AND VARIATION IN THE SUBTRIBE CATASETINAE (ORCHIDACEAE)
TLDR
The pollen throwing apparatus and the pollination mechanisms of the various genera are discussed on the basis of field observations and the production of separate male and female inflorescences is explained as being triggered by the relative amounts of sunlight received by the plants. Expand
Preliminary Studies in the Genus Stanhopea (Orchidaceae)
This preliminary study is an attempt to bring together the knowledge of Taxonomy, Morphology, Phylogeny and Pollination of the species preparatory to a formal revision of the genus. New information,Expand
Food related adaptations in stream living caddisfly larvae feeding on leaves
TLDR
From the nine most common caddisfly shredders in a South Swedish stream five were most abundant in the uppermost section, and food was more effectively used for growth here than further downstream. Expand
Beobachtungen über das Bewegungsverhalten des Pollinariums von Catasetum Jimbriatum Lindl. während Abschuß, Flug und Landung1)2)
Summary The extremely quick movement of the pollinarium of Catasetum fimbriatum L indl . during the launching, flight, and landing is analysed by means of pictures consisting of selected frames fromExpand
ITc hieh polien-donation success suggested for Catastum in
  • 1981
An obvious stipe rsists after pollination
    Calculatod as the area within which a second viscidium would contact the first pollinarium divided by the area within which most pollinaria strikc
      Forcible emplacement and attachment of pollinarium is characteristic of Catasetum, except for the C. dor alliance (1)
        ...
        1
        2
        ...