A Pyralid Moth (Lepidoptera) as Pollinator of Blunt-Leaf Orchid

(excerpt) As early as 1912, mosquitoes were observed bearing the pollen masses (pollinia) of the blunt-leaf orchid, Habenaria obtusata (Pursh) Richardson, in Reese\u27s Bog, a cedar swamp at the north end of Burt Lake, Cheboygan County, Michigan, near the campus of the University of Michigan Biological Station (Dexter 1913)

Conservation Pakage for Modal Ecorace

Conserving biodiversity is about genetic variety, species, habitats and ecosystems. All are important, but it is often most appropriate, practical and effective to focus on species. With modern conservation awareness, there is a welcome and popular commitment to maintaining the diversity of species in India. Nevertheless, over the last 50 years, we have witnessed the severe decline of many once widespread and familiar species, such as tropical Tasar silkworm Antherea mylitta D. Conservation is not just about avoiding extinctions, but about restoring or recovering species populations to secure levels and preventing other species from reaching such a perilous situation in the first place. Species, by their very nature, have specific ecological requirements. They may appear to share the same habitat with many others but each has a different, specific niche. It is what sets them apart, and makes them what they are. Habitat loss has historically been a factor in species decline. However, the way existing habitats are managed is also important

Comparison between the Wheeler-Thanhauser Orchid Collection at Ball State University and the Orchid Collection Riyadh, Saudi Arabia

The beauty, complexity as well as the implausible diversity of the orchid flowers are unrivaled in the world. Orchids can be found in the equatorial tropics as well as the arctic tundra. The main logic behind the diversity of the orchid plants is in their ability to adapt to the environment normally located. There are numerous varieties of orchids that normally thrive in a wide range of different growing conditions, making it possible to find an orchid in almost any man-made environment as well. In this study, a comparison of orchids from two diverse collections was made utilizing printed materials (books and articles), and online database resources. The detailed analysis of the descriptive information of orchid genera with similar features between the two collections is presented.Department of BiologyThesis (M.A.

The olfactory basis of orchid pollination by mosquitoes.

Mosquitoes are important vectors of disease and require sources of carbohydrates for reproduction and survival. Unlike host-related behaviors of mosquitoes, comparatively less is understood about the mechanisms involved in nectar-feeding decisions, or how this sensory information is processed in the mosquito brain. Here we show that Aedes spp. mosquitoes, including Aedes aegypti, are effective pollinators of the Platanthera obtusata orchid, and demonstrate this mutualism is mediated by the orchid's scent and the balance of excitation and inhibition in the mosquito's antennal lobe (AL). The P. obtusata orchid emits an attractive, nonanal-rich scent, whereas related Platanthera species-not visited by mosquitoes-emit scents dominated by lilac aldehyde. Calcium imaging experiments in the mosquito AL revealed that nonanal and lilac aldehyde each respectively activate the LC2 and AM2 glomerulus, and remarkably, the AM2 glomerulus is also sensitive to N,N-diethyl-meta-toluamide (DEET), a mosquito repellent. Lateral inhibition between these 2 glomeruli reflects the level of attraction to the orchid scents. Whereas the enriched nonanal scent of P. obtusata activates the LC2 and suppresses AM2, the high level of lilac aldehyde in the other orchid scents inverts this pattern of glomerular activity, and behavioral attraction is lost. These results demonstrate the ecological importance of mosquitoes beyond operating as disease vectors and open the door toward understanding the neural basis of mosquito nectar-seeking behaviors

The Victorian Naturalist

v.44 (1927-1928

Diverse pollination systems of the twin-spurred orchid genus Satyrium in African grasslands

The large terrestrial orchid genus Satyrium underwent evolutionary radiations in the Cape floral region and the grasslands of southern and eastern Africa. These radiations were accompanied by tremendous diversification of the unusual twin-spurred flowers that characterize the genus, but pollination data required to interpret these patterns of floral evolution have been lacking for grassland species in the genus. Here we document pollinators, nectar properties, and levels of pollination success for 11 grassland Satyrium species in southern and south-central Africa. Pollinators of these species include bees, beetles, butterflies, hawkmoths, noctuid moths, long-proboscid flies, and sunbirds. Most species appear to be specialized for pollination by one functional pollinator group. Long-proboscid fly pollination systems are reported for the first time in Satyrium (in S. macrophyllum and a high-altitude form of S. neglectum). Floral morphology, especially spur length and rostellum structure, differs markedly among plants with different pollinators, while nectar volume, concentration, and sugar composition are fairly uniform across species. Most taxa exhibited high levels of pollination success (>50% of flowers pollinated), a trend that can be attributed to the presence of nectar in the twin spurs

Floral scent emission and pollinator attraction in two species of Gymnadenia (Orchidaceae)

We investigated scent composition and pollinator attraction in two closely related orchids, Gymnadenia conopsea (L.) R.Br. s.l. and Gymnadenia odoratissima (L.) Rich. in four populations during the day and night. We collected pollinators of both species using hand nets and sampled floral odour by headspace sorption. We analysed the samples by gas chromatography with mass spectrometry to identify compounds and with electroantennographic detection to identify compounds with physiological activity in pollinators. In order to evaluate the attractiveness of the physiologically active compounds, we carried out trapping experiments in the field with single active odour substances and mixtures thereof. By collecting insects from flowers, we caught eight pollinators of G. conopsea, which were members of four Lepidoptera families, and 37 pollinators of G. odoratissima, from five Lepidopteran families. There was no overlap in pollinator species caught from the two orchids using nets. In the scent analyses, we identified 45 volatiles in G. conopsea of which three (benzyl acetate, eugenol, benzyl benzoate) were physiologically active. In G. odoratissima, 44 volatiles were identified, of which seven were physiologically active (benzaldehyde, phenylacetaldehyde, benzyl acetate, 1-phenyl-2,3-butandione, phenylethyl acetate, eugenol, and one unknown compound). In field bioassays using a mixture of the active G. odoratissima compounds and phenylacetaldehyde alone we caught a total of 25moths, some of which carried Gymnadenia pollinia. A blend of the active G. conopsea volatiles placed in the G. odoratissima population did not attract any pollinators. The two orchids emitted different odour bouquets during the day and night, but G. odoratissima showed greater temporal differences in odour composition, with phenylacetaldehyde showing a significant increase during the night. The species differed considerably in floral odour emission and this differentiation was stronger in the active than non-active compounds. This differentiation of the two species, especially in the emission of active compounds, appears to have evolved under selection for attraction of different suites of Lepidopteran pollinator