Hoodia (pronounced /ˈhʊdiːə/) is a genus of 13 species in the flowering plant family Apocynaceae, under the subfamily Asclepiadoideae. They are stem succulents, described as "cactiform" because of their remarkable similarity to the unrelated cactus family. They can reach up to 1m high and have large flowers, often with flesh colour and strong smell.Many Hoodia species are protected plants, typical of the Namib Desert, ranging from Central Namibia to southern Angola, especially in plains and rocky areas. Common names include "Bushman's Hat" and "Queen of the Namib".Several species are grown as garden plants, and one species, Hoodia gordonii, is being investigated for use as an appetite suppressant.On January 18, 2008, the Botanic Gardens Conservation International (representing botanic gardens in 120 countries) stated that "400 medicinal plants are at risk of extinction, from over-collection and deforestation, threatening the discovery of future cures for disease." These included Yew trees (the bark was used for cancer drugs, paclitaxel, although current licenced syntheses do not); Hoodia (from Namibia, source of weight loss drugs); half of Magnolias (used as Chinese medicine for 5,000 years to fight cancer, dementia and heart disease); and Autumn crocus (for gout). The group also found that 5 billion people benefit from traditional plant-based medicine for health care SpeciesHoodiaHoodia alstoniiHoodia cactusHoodia currorii (syn. H. lugardii, H. macrantha)Hoodia dregeiHoodia flavaHoodia gordonii (syn. Stapelia gordonii, H. barklyi, H. burkei, H. longispina)Hoodia juttaeHoodia mossamedensisHoodia officinalis (syn. H. delaetiana)Hoodia parvifloraHoodia pedicellataHoodia pilifera (syn. H. annulata, H. grandis, H. pillansii)Hoodia ruschii (Queen of the Namib)Hoodia triebneri (syn. H. foetida) References^ Stevens PF (2001 onwards). Gentianales. Angiosperm Phylogeny Website (Missouri Botanical Gardens). Version 7, May 2006. Retrieved July 14, 2006.^ BBC NEWS, Medical plants 'face extinction'