If you saw it in the background of an old Star Trek episode, you'd laugh bemusedly and think "how quaint of them to imagine such strange flora, and how much more handsome, wise, and well art-directed we are today." Truth being stranger than fiction, Rafflesia Arnoldii is real. And it's the world's largest, strangest, stinkiest flower.

Territory

Named for Sir Stamford Raffles, the spunkily-named founder of the British colony of Singapore, this flower can be found in the sweaty lowland forests of Southeast Asia, namely Borneo, Sumatra, and Java. With these forests undergoing continued burning for agricultural development and timber concessions, Arnoldii and all 17 members of its genus are either threatened or endangered. Time is running out on this oddity.

Life cycle and Appearance

Arnoldii ranks right up there with anglerfish and osedax for wildest reproductive practices. For most of its life, it's invisible, existing as non-lethal parasitic threads within a Tetrastigma vine. Arnoldii can't produce chlorophyll, and gets all of its nutrition from the host plant. Where the host vine drapes across the undisturbed jungle floor, Arnoldii may find purchase to germinate the world's largest flower. But even when it does so, it ain't quick. It takes nine months for a bud to form.

How do you find one? Follow your nose. The plant has evolved to attract flies as its pollinators, and has developed a stench like that of a decaying cadaver. To quote Swedish entomologist E.G. Mjoberg in 1928, it is "a penetrating smell more repulsive than any buffalo carcass in an advanced stage of decomposition" Yum.

All told, it is a horribly inefficient reproducer. 80-90% of the buds simply rot before they bloom. Some of those that survive are mistakenly eaten by carrion feeders. The flowers are unisexual and plants near one another tend to be of the same sex. Males that do make it to full bloom have only 5–7 days of "life" to be stinky enough to trick flies into landing on them. Then the flies have to be lured away to a distant female that happens to be in bloom for the same period. Despite the challenges, it survives.

The bud itself has no leaves or stems, just five thick, giant, orange-red petals that curve back away from a hollow sphere with a hole for flies to enter. In the center of the sphere is a yellowish disc with darker red-orange spikes sticking up from it. The massive petals are mottled with yellow-orange, irregular, warty bumps. The surface of the sphere is covered with a lighter, bumpier, denser version of this same pattern, with a rim that features translucent white spots that let light through to its interior.

Did I mention it's huge? Reinforce your lapels, because it has a diameter of nearly a meter (3 feet for the imperialists) and can weigh up to 11 kg (nearly 25 pounds). (Insert humorous Malaysian prom scene here.) Note that this means that this creature has a sex organ around 1,000,000 times as large as the size of its body. For comparison, if humans worked this way, when a six-foot-tall woman in Carlton, Kansas wanted to reproduce, her vagina would grow to a diameter that would just about reach the Canadian and Mexican borders.

Winning on a technicality

"But wait!" I hear you cry. "Isn't the 2 meter tall, phallic purple tower of Amorphophallus Titanium larger?" Not exactly. Though, indeed, huge, what looks like a single flower is actually an inflorescence, an organ with massive amounts of small flowers all over it (like a daisy), and not a true flower by botanists' standards. The good news: it also relies on carrion-mimicry, and contributes to the forest putrescence as readily.

Despite its stench, reproductive challenges, and threatened habitat, thousands of tourists travel to Sabah in Borneo annually, hoping on hikes through the forest to catch a glimpse of the rare Arnoldii. This perhaps is the greatest hope for its survival, as locals look to the ecotourism to boost their economy.


Sources
  • http://homepages.wmich.edu/~tbarkman/rafflesia/Rafflesia.html
  • NewScientest's 100 Thing to Do Before You Die, Profile Books
  • http://www.earlham.edu/~givenbe/Rafflesia/rafflesia/biodiv2.htm
Pictures
  • http://www.lostworldarts.com/asia/rafflesia_2.htm
  • http://www.science.siu.edu/parasitic-plants/Rafflesiaceae/Raff.arn.page.html