rafflesia

''Rafflesia'' (), or stinking corpse lily, is a genus of parasitic flowering plants in the family Rafflesiaceae. The species have enormous flowers, the buds rising from the ground or directly from the lower stems of their host plants; one species has the largest flower in the world. Plants of the World Online lists up to 41 species from this genus; all of them are found throughout Southeast Asia.

Western Europeans first learned about plants of this genus from French surgeon and naturalist Louis Deschamps when he was in Java between 1791 and 1794; but his notes and illustrations were seized by the British in 1798 and were not available to Western scientists until 1861. The first British person to see one was Joseph Arnold in 1818, in the Indonesia rainforest in Bengkulu, Sumatra, after a Malay servant working for him discovered a flower and pointed it out to him. The flower, and the genus, was later named after Stamford Raffles, the leader of the expedition and the founder of the British colony of Singapore.

The following is from Arnold's account of discovering the flower:

Vivid contemporary accounts documenting some of the most inaccessible species of Rafflesia are described in the popular science book, '' Pathless Forest: The Quest to Save the World's Largest Flowers'', by botanist Chris Thorogood based at the University of Oxford Botanic Garden.

Description

The plant has no stems, leaves or roots. It is a holoparasite of vines in the genus ''Tetrastigma'' (a plant in the Vitaceae, the grape vine family), 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-petalled flower. In some species, such as ''Rafflesia arnoldii'', the flower may be over in diameter, and weigh up to . A ''Rafflesia'' that flowered in West Sumatra in 2019 was measured to be almost in diameter, the largest flower ever recorded – wider than the flower reported as the largest in 2017. Even one of the smallest species, '' R. baletei'', has diameter flowers. A team of morphologists and geneticists headed by Prof. Charles Davis of Harvard has discovered an important difference between ''Rafflesia'' spp. and the very similar '' Sapria'' spp. In both genera the petals are now described as sepals (or more correctly as "petaloid tepals") instead of vaguely defined "perigon lobes". In ''Sapria'', the "diaphragm" is a true corona while in ''Rafflesia'' the diaphragm is made up of adnate petals to form a dome, the true corona being greatly reduced.

The flowers look and smell like rotting flesh. The foul odour attracts insects such as carrion flies, which transport pollen from male to female flowers. Most species are dioecious, having separate male and female flowers, but a few (''R. baletei'' and '' R. verrucosa'') have hermaphroditic flowers. Little is known about seed dispersal. Tree shrews and other forest mammals eat the fruits. The extremely tiny seeds have extremely tiny elaiosomes, and are thus most likely dispersed by ants. The seeds are packed into berries, each of which contains hundreds of thousands of seeds.

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 unrelated to each other. ''Rafflesia arnoldii'' has the largest ''single'' flower of any flowering plant, at least in terms of weight. '' Amorphophallus 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.

' horizontal transfer of genes from their host plants. This is well known among bacteria, but not higher organisms. It occurs in the Horizontal gene transfer">horizontal transfer of genes from their host plants. This is well known among bacteria, but not higher organisms. It occurs in the mitochondria (originally derived from bacteria) found within the cells of ''Rafflesia''; these appear to have exchanged genes with the mitochondria of the host tissue.

Names

In Indonesian and Malaysian language">Malaysian, it is known as ''padma''. The species ''R. arnoldii'' is known as ''padma raksasa'' ("giant ''padma''"). In Javanese it is called ''patma''. In Malay, the 'normal' ''R. hasseltii'' is vernacularly known as ''pakma'', ''patma'' or ''ambai-ambai'', whereas the goliath ''R. arnoldii'' from Sumatra is called ''krubut'' or ''kerubut'', 'great flower'. The words ''padma'', ''pakma'' or ''patma'' originate etymologically from the word पद्म (''padma''), Sanskrit for ' lotus'.

In English ''Rafflesia'' is known as the stinking corpse lily. It is also known as "corpse flower", or ''bunga bangkai'' in Indonesian, a name that more commonly refers to the titan arum (''Amorphophallus titanum'') of the family Araceae">Amorphophallus titanum">titan arum (''Amorphophallus titanum'') of the family Araceae. The type species ''arnoldii'' has been called the "monster flower".

Taxonomy

Robert Brown (Scottish botanist from Montrose)">Robert Brown