Rafflesia is a genus of parasitic flowering plants. It contains approximately 28 species (including four incompletely characterized species as recognized by Willem Meijer in 1997), all found in southeastern Asia.
The plant has no stems, leaves or true roots. It is an endoparasite of vines in the genus Tetrastigma (Vitaceae), spreading its absorptive organ, the haustorium, inside the tissue of the vine. The only part of the plant that can be seen outside the host vine is the five-petaled flower. In some species, such as Rafflesia arnoldii, the flower may be over 100 centimetres (39 in) in diameter, and weigh up to 10 kilograms (22 lb). Even the smallest species, R. baletei, has 12 cm diameter flowers. The flowers look and smell like rotting flesh, hence its local names which translate to "corpse flower" or "meat flower" (see below). The foul odor attracts insects such as flies, which transport pollen from male to female flowers. Most species have separate male and female flowers, but a few have bisexual flowers. Little is known about seed dispersal. However, tree shrews and other forest mammals eat the fruits and disperse the seeds.
The name "corpse flower" applied to Rafflesia can be confusing because this common name also refers to the titan arum (Amorphophallus titanum) of the family Araceae. Moreover, because Amorphophallus has the world's largest unbranched inflorescence, it is sometimes mistakenly credited as having the world's largest flower. Both Rafflesia and Amorphophallus are flowering plants, but they are only distantly related. Rafflesia arnoldii has the largest "single" flower of any flowering plant, at least in terms of weight. A. titanum has the largest "unbranched" inflorescence, while the talipot palm (Corypha umbraculifera) forms the largest "branched" inflorescence, containing thousands of flowers; the talipot is monocarpic, meaning the individual plants die after flowering.
Gunung Gading National Park has a very special star attraction - the Rafflesia, the world’s largest flower - and the park is one of the best places in Asia to view the Rafflesia’s spectacular blooms. Gunung Gading sprawls across four jungle-clad mountain peaks, and its dense primary rainforest is criss-crossed by crystal clear streams and waterfalls. Gunung Gading was gazetted as a park in 1st August 1983 primarily to provide a conservation zone for the protection of the Rafflesia. It was opened to the public in 1994 and visitors can now view one of the most spectacular plants found on the planet. The park is easily accessible from Kuching,Sarawak,Malaysian Borneo, on a day trip. Those wishing to stay longer can enjoy Gunung Gading’s other attractions - particularly its rainforest scenery, waterfalls and jungle trails. Some of these trails lead to the peaks of the mountains that make up the park and offer challenging jungle treks.