Angraecum sesquipedale

To me, there are 3 orchids out there that truly inspire the imaginative and intellectual parts of our being. Dendrophylax lindenii, Dimorphorchis lowii, and Angraecum sesquipedale. Each one of these orchids has some sort of amazing mechanism or morphological feature that distinguishes it within the orchid world. Dendrophylax lindenii is stemless and leafless, Dimorphorchis lowii has true dimorphic flowers. So what is it that makes Angraecum sesquipedale unique. Why has the story of its discovery been passed down for nearly 200 years?

Angraecum sesquipedale, has off white flower that is nocturnally fragrant. What makes this flower so interesting is that it has a 10-12 inch long nectar tube, with only the very end portion containing any nectar. The Purpose of a nectar tube is to attract an insect with the proper mouth parts to lap up the nectar, in this case a moth. Which really makes you wonder, is there really a moth out there with a 12" proboscis?

Many people believe Angraecum sesquipedale was discovered by Charles Darwin, however it was actually discovered by a Frenchmen name Louis-Marie Aubert du Petit-Thouars in 1798. It wasn't until 1862 that Charles Darwin published any work on the species. This is where things get exciting (if you're a nerd like me). Darwin was sent several flowers an asked to analyze them. He developed a theory that their was a moth in existence that has a long enough proboscis to reach the nectar in the bottom of the nectar tube, and then pollinate the flower. This was the only logical conclusion, for moths that could not reach the bottom would simply not seek out the flower, there for the species would not continue to exist in the wild.  unfortunately at the time no such moth was discovered leading to a large amount of skepticism, even from his own followers.  But wait there is more! In 1903 such a moth was discovered and identified as a subspecies of the African Hawk Moth! Is your heart beating as fast as mine? Granted I probably have a little help from all the caffeine I have been consuming. It was given the name Xanthopan morgani praedicta. The epithet praedicta in honor of Darwin's prediction of its existence. This discover was considered to be a triumph of the theory of evolution and has been used a specific model for co-evolution ever sense.

Works Cited

"Angraecum Sesquipedale - Star of Betlehem Orchid - Angraecum Encyclopedia." Genus Angraecum - Angraecum Encyclopedia. Web. 03 Feb. 2011. <http://www.angraecum.org/Species/Angraecum/Angraecum_sesquipedale.htm>.

"Xanthopan Morgani." Wikipedia, the Free Encyclopedia. Web. 03 Feb. 2011. <http://en.wikipedia.org/wiki/Xanthopan_morgani>.