When looking through the 520 "Orchid" images at Acclaim Images.com this A Brightly Colored Orchid Against a Black Background was a favorite.
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Description:
A Brightly Colored Orchid Against a Black Background
A brightly colored magneta lucky mongkorn orchid from Thailand of the cattleya species

Some related terms for more images:
paul whitehead,  colorful,  thai orchids,  plant,  flower,  red,  plants,  colourful,  flowers,  orchidae,  orchids of thailand,  magneta,  cattleya,  lucky mongkorn,