The magnificent Rafflesia, the largest flowers in the world, can grow up to 40 inches in diameter, sporting dramatic reddish petals that smell like rotting meat.
Like a giant red bowl lined with yellow spotted petals, Rafflesia exude a strong small that is similar to what you might expect to find near a long-rotting carcass. Not pollinated by insects seeking nectar, Rafflesia are believed to be pollinated by flies. The flowers are endoparasites that requires the presence of Tetrastigma (wild grape vine) hosts, without which they will not grow.
The Rafflesia was first noted by British naturalist Joseph Arnold, and named for the leader of the expedition, Sir Thomas Stamford Raffles. The Rafflesia arnoldii was later named in Arnold's honor. It has since been named the official flower of Surat Thani province, but habitat losses and collection by humans are causing numbers to dwindle.
The cooked buds or flowers of the Rafflesia can be used to help fever or backache or even as a sexual stimulant, however western medicine doesn't recognize any medical use for the flower.
The largest species of Rafflesia, Rafflesia arnoldii, does not grow in Thailand, but three other large species do - and they are celebrated by the national park, where they can be found in abundance.
The Rafflesia is a distant relative of the other gigantic "corpse flower", the Amorphophallus titanum.