Amorphophallus (from Ancient Greek, "without form, misshapen" + phallos, "penis", referring to the shape of the prominent spadix) is a large genus of some 200 tropical and subtropical tuberous herbaceous plants from the Arum family (Araceae), native to Asia, Africa, Australia and various oceanic islands.[1] [2] A few species are edible as "famine foods" after careful preparation to remove irritating chemicals.[3] The genus includes the Titan arum (A. titanum) of Indonesia, which has the largest inflorescence of any plant in the genus, and is also known as the 'corpse flower' for the pungent odour it produces during its flowering period, which can take up to seven years of growth before it occurs.[4]
The oldest systematic record of the plants was in 1692, when Van Rheede tot Drakenstein published descriptions of two plants. The name "Amorphophallus" was first mentioned in 1834 by the Dutch botanist Blume.[5] Between 1876 and 1911, Engler merged a number of other genera into Amorphophallus, with a final monograph published in 1911.[5]
These are typical lowland plants, growing in the tropical and subtropical zones of the paleotropics, from West Africa through the Pacific Islands. None of them are found in the Americas, although a remarkably similar but not closely related genus, Dracontium, has evolved there. Most species are endemic. They grow preferentially on disturbed grounds, such as secondary forests.[6]
These small to massive plants grow from a subterranean tuber. Amorphophallus tubers vary greatly from species to species, from the quite uniformly globose tuber of A. konjac to the elongated tubers of A. longituberosus and A. macrorhizus to the bizarre clustered rootstock of A. coaetaneus.It can grow upto 6 feet in height and the weight of these tubers range from as little as ten grams (3/10ths of an ounce) in Amorphophallus pusillus of Vietnam[7] to as much as 305 pounds (139 kg) for Amorphophallus titanum, a 14,000 fold difference in weight. From the top of this tuber a single leaf, which can be several meters across in larger species, is produced atop a trunk-like petiole followed, on maturity, by a single inflorescence. This leaf consists of a vertical leaf stalk and a horizontal blade, which may consist of a number of small leaflets. The leaf lasts one growing season. The peduncle (the primary flower stalk) can be long or short.
As is typical of the Arum family, these species develop an inflorescence consisting of an elongate or ovate spathe (a sheathing bract) which usually envelops the spadix (a flower spike with a fleshy axis). The spathe can have different colors, but mostly brownish-purple or whitish-green. On the inside, they contain ridges or warts, functioning as insect traps.
The plants are monoecious. The spadix has tiny flowers: female flowers, no more than a pistil, at the bottom, then male flowers, each with one stamen, and then a blank sterile area. This last part, called 'the appendix', consists of sterile flowers, called staminodes, and can be especially large. The flowers do not have corollas.
Mature female flowers are usually receptive for only 1 day. In many species, the inflorescence emits a scent of decaying flesh in order to attract insects, though a number of species give off a pleasant odor. Through a number of ingenious insect traps, pollinating insects that entered a spathe when female flowers were receptive remain inside the spathe for about 1 day while male flowers mature and release pollen. Pollen falls on these insects, and they carry pollen as they exit the spathe and can pollinate female flowers in another spathe. Amorphophallus species are used as food plants by the larvae of some Lepidoptera (butterfly and moth) species including Palpifer sexnotatus and Palpifer sordida.
Pollinated flowers usually each develop into a globose berry, a fruit. The berries are red, orange-red, white, white and yellow, or blue, depending on the species.
The species Amorphophallus titanum, 'corpse flower' or titan arum, has the world's largest unbranched inflorescence, with a height of up to 2.5m (08.2feet) and a width of 1.5m (04.9feet). After an over 1.2m (03.9feet)-tall flower opened at Chicago Botanic Gardens on September 29, 2015, thousands lined up to see and smell it. The floriculturalist described it as smelling "like roadkill, a barnyard, a dirty diaper, very strong, a little bit of mothball smell too". Native to the Indonesian rainforest, it takes about 10 years to blossom. Dubbed "Alice", its bloom was broadcast via live webcam. It is one of two plants at the Chicago Botanic Gardens, which kept open until 2 am on September 30 to accommodate visitors.[8]
A runner-up is Amorphophallus gigas, which is taller, but has a somewhat smaller inflorescence.
Amorphophallus konjac tubers are used to make, a Japanese thickening agent and edible jelly containing glucomannan.
Some species are called voodoo-lily, as are some species of Typhonium (also in the Araceae).[9] [10]
The genus was divided into 4 subgenera based on phylogenetic analysis in 2017,[11] with a number of SE Asian genera currently unplaced:
| Image | Name | Year | Distribution |
|---|---|---|---|
| Amorphophallus adamsensis | 2013 | Philippines | |
| Amorphophallus angulatus | 1994 | Borneo (Sarawak) | |
| Amorphophallus ardii[12] | 2020 | Sulawesi. | |
| Amorphophallus asper | 1911 | Sumatera | |
| Amorphophallus bangkokensis | 1941 | Thailand | |
| Amorphophallus beccarii | 1880 | Sumatera | |
| Amorphophallus borneensis | 1911 | Borneo | |
| Amorphophallus boyceanus | 2001 | Thailand and Peninsular Malaysia | |
| Amorphophallus brachyphyllus | 2001 | Borneo (Kuching) | |
| Amorphophallus bufo | 1909 | Malaysia | |
| Amorphophallus calcicolus | 2021 | Philippines | |
| Amorphophallus caudatus | 2020 | Philippines | |
| Amorphophallus cidarioides | 2020 | Philippines | |
| Amorphophallus commutatus | 1879 | Western India | |
| Amorphophallus costatus | 1994 | Borneo (Sarawak, Kalimantan). | |
| Amorphophallus declinatus | 1994 | Philippines | |
| Amorphophallus decus-silvae : West-Java giant amorphophallus | 1920 | Java | |
| Amorphophallus discophorus | 1920 | Java | |
| Amorphophallus eburneus | 1989 | Borneo (Sarawak) | |
| Amorphophallus elegans | 1922 | Peninsular Malaysia | |
| Amorphophallus flammeus | 2022 | Philippines | |
| Amorphophallus fontarumii | 2022 | Philippines (Luzon) | |
| Amorphophallus fornicatus | 2020 | Philippines (Luzon) | |
| Amorphophallus galbra | 1893 | New Guinea to N. Australia. | |
| Amorphophallus gigas : Sumatra giant amorphophallus | 1862 | Sumatra | |
| Amorphophallus hewittii | 1920 | Borneo | |
| Amorphophallus hirsutus | 1862 | Nicobar Islands, W. Sumatra | |
| Amorphophallus hottae | 1992 | Borneo (Sabah, Sarawak). | |
| Amorphophallus infundibuliformis | 1994 | Borneo | |
| Amorphophallus julaihii | 2004 | Borneo (Sarawak). | |
| Amorphophallus juliae | 2010 | Borneo (Sarawak) | |
| Amorphophallus koratensis Gagnep. | 1941 | Cambodia, Laos, Thailand | |
| Amorphophallus lambii Mayo & Widjaja | 1982 | Borneo | |
| Amorphophallus linguiformis Hett. | 1994 | Borneo (Kalimantan). | |
| Amorphophallus longispathaceus Engl. & Gehrm. | 1911 | Philippines (Mindanao) | |
| Amorphophallus longistylus Kurz ex Hook.f. | 1893 | Andaman Islands. | |
| Amorphophallus luzoniensis | 1915 | Philippines (Luzon) | |
| Amorphophallus manta | 1994 | Sumatra to Peninsula Malaysia. | |
| Amorphophallus merrillii | 1912 | Philippines | |
| Amorphophallus minimus | 2021 | Philippines | |
| Amorphophallus myosuroides | 2006 | Laos | |
| Amorphophallus niahensis | 2010 | Borneo (Sarawak) | |
| Amorphophallus obovoideus | 1922 | Sumatra | |
| Amorphophallus obscurus | 2001 | Thailand | |
| Amorphophallus ongsakulii | 2006 | Laos | |
| Amorphophallus opertus | 1994 | Vietnam | |
| Amorphophallus paeoniifolius : Whitespot giant arum, elephant yam | 1977 | Andaman Island, Assam, Bangladesh, Borneo, Cambodia, China South-Central, China Southeast, East Himalaya, Hainan, India, Java, Laos, Lesser Sundas Is., Malaya, Maluku, Myanmar, New Guinea, Northern Territory, Philippines, Sri Lanka, Sulawesi, Sumatra, Taiwan, Thailand, Vietnam | |
| Amorphophallus palawanensis | 1992 | Philippines | |
| Amorphophallus pendulus : Brunei amorphophallus | 1986 | Borneo (Brunei, Sarawak) | |
| Amorphophallus plicatus | 1936 | Sulawesi. | |
| Amorphophallus polyanthus | 2001 | Thailand | |
| Amorphophallus prainii | 1893 | Laos, Malaya, Sumatera, Thailand | |
| Amorphophallus pulchellus | 2013 | Laos | |
| Amorphophallus pusillus | 1994 | Vietnam | |
| Amorphophallus ranchanensis | 2007 | Borneo (Sarawak) | |
| Amorphophallus rayongii | 2020 | Philippines | |
| Amorphophallus rostratus | 1994 | Vietnam | |
| Amorphophallus rugosus | 1994 | Borneo (Sabah) | |
| Amorphophallus sagittarius | 1953 | Java | |
| Amorphophallus salmoneus | 1994 | Philippines | |
| Amorphophallus scaber | 1994 | Philippines | |
| Amorphophallus serrulatus | 2006 | Thailand | |
| Amorphophallus spectabilis | 1879 | Java | |
| Amorphophallus sumawongii | 1985 | Thailand | |
| Amorphophallus terrestris | 2012 | Thailand | |
| Amorphophallus tinekeae | 2001 | Borneo | |
| Amorphophallus titanum : Titan arum, krubi (largest flower structure on earth) | 1879 | Sumatra | |
| Amorphophallus urceolatus | 2020 | Philippines | |
| Amorphophallus variabilis | 1873 | Jawa to Lesser Sunda Islands, Philippines | |
| Amorphophallus venustus | 2001 | Borneo | |
| Amorphophallus verticillatus | 1994 | Vietnam | |
| Amorphophallus yaoi | 2020 | Philippines | |
| Image | Name | Year | Distribution |
|---|---|---|---|
| Amorphophallus albispathus | 1994 | Thailand | |
| Amorphophallus albus | 1984 | China (Sichuan, Yunnan). | |
| Amorphophallus annulifer | 1994 | Java | |
| Amorphophallus asterostigmatus | 1992 | Thailand | |
| Amorphophallus bantae | 2024 | Thailand (Sa Kaeo) | |
| Amorphophallus bognerianus | 2009 | India (Arunachal Pradesh) | |
| Amorphophallus carneus | 1904 | Malayasia, Thailand | |
| Amorphophallus chlorospathus | 1893 | India, Myanmar | |
| Amorphophallus coudercii | 1985 | Cambodia, Laos, Thailand and Vietnam | |
| Amorphophallus curvistylis | 1994 | Thailand | |
| Amorphophallus echinatus | 1985 | Thailand. | |
| Amorphophallus excentricus | 1994 | Thailand, Malaysia (Pulau Langkawi) | |
| Amorphophallus fallax | 2012 | Vietnam | |
| Amorphophallus flotoi | 2018 | Cambodia, Laos, Thailand, Vietnam | |
| Amorphophallus fuscus | 2006 | Thailand. | |
| Amorphophallus glaucophyllus | 2006 | Thailand. | |
| Amorphophallus haematospadix | 1893 | Thailand, Malaysia (Pulau Langkawi) | |
| Amorphophallus hohenackeri | 1911 | India | |
| Amorphophallus kachinensis | 1911 | China (Yunnan, Guangxi), Laos, Myanmar, Thailand | |
| Amorphophallus konjac : Devil's tongue, elephant foot, elephant-yam, leopard palm, snake palm, umbrella arum, voodoo lily | 1858 | China (Yunnan) | |
| Amorphophallus khammouanensis | 2015 | Laos. | |
| Amorphophallus krausei | 1911 | China (Yunnan), Laos, Myanmar, Thailand | |
| Amorphophallus kuznetsovii | 2012 | Vietnam | |
| Amorphophallus lacourii | 1878 | Cambodia, Laos, Thailand, Vietnam | |
| Amorphophallus lanceolatus | 2012 | Vietnam | |
| Amorphophallus longituberosus | 1911 | Bangladesh, Malaya, Thailand | |
| Amorphophallus macrophyllus | 2012 | Thailand, Vietnam | |
| Amorphophallus maxwellii | 1994 | Thailand | |
| Amorphophallus nicolsonianus | 1986 | India (Kerala). | |
| Amorphophallus napalensis | 1985 | Bangladesh, Bhutan, Nepal, Myanmar, and India | |
| Amorphophallus purpurascens | 1893 | Myanmar | |
| Amorphophallus ravenii | 2018 | Laos | |
| Amorphophallus rhizomatosus | 1994 | Laos, Vietnam | |
| Amorphophallus saraburensis | 1941 | Thailand. | |
| Amorphophallus schmidtiae | 2006 | Laos | |
| Amorphophallus scutatus | 2001 | Thailand. | |
| Amorphophallus smithsonianus | 1989 | India | |
| Amorphophallus tenuistylis | 1994 | Cambodia, Thailand | |
| Amorphophallus tenuispadix | 1994 | Thailand | |
| Amorphophallus wasa | 2022 | Myanmar | |
| Image | Name | Year | Distribution |
|---|---|---|---|
| Amorphophallus aberrans Hett. | 1994 | Thailand | |
| Amorphophallus amygdaloides Hett. & Sizemore | 2001 | SW. Thailand | |
| Amorphophallus angustispathus Hett. | 1994 | Myanmar | |
| Amorphophallus atrorubens Hett. & Sizemore | 2001 | NE. Thailand. | |
| Amorphophallus atroviridis Hett. | 1994 | central Thailand | |
| Amorphophallus bonaccordensis Sivad. & N.Mohanan | 1994 | Kerala | |
| Amorphophallus brevispathus Gagnep. | 1941 | Central Thailand | |
| Amorphophallus bulbifer (Schott) Blume | 1837 | Indian Subcontinent to Myanmar | |
| Amorphophallus carnosus Engl. | 1911 | S. Andaman Islands | |
| Amorphophallus cicatricifer | 1994 | SW. Thailand | |
| Amorphophallus cirrifer | 1924 | Thailand | |
| Amorphophallus coaetaneus | 1986 | China (Yunnan, Guangxi), Vietnam | |
| Amorphophallus croatii | 2006 | Laos | |
| Amorphophallus cruddasianus | 1898 | Laos, Myanmar, Thailand | |
| Amorphophallus dunnii Tutcher | 1911 | SE. China | |
| Amorphophallus dzui Hett. | 2001 | Vietnam | |
| Amorphophallus elatus | 1893 | Thailand, Malaysia, Myanmar | |
| Amorphophallus gallowayi | 2006 | Laos | |
| Amorphophallus glossophyllus | 1994 | Vietnam | |
| Amorphophallus harmandii Engl. & Gehrm. | 1911 | Indochina | |
| Amorphophallus hayi Hett. | 1994 | SE China, northern Vietnam | |
| Amorphophallus henryi N.E.Br. (Taiwan amorphophallus) | 1903 | Taiwan | |
| Amorphophallus hirtus N.E.Br. | 1903 | Taiwan | |
| Amorphophallus interruptus Engl. & Gehrm. | 1911 | northern Vietnam | |
| Amorphophallus josefbogneri Hett. | 2006 | SW. Thailand | |
| Amorphophallus kiusianus (Makino) Makino | 1913 | SE. China, Japan (Shikoku, S. Kyushu) to Taiwan | |
| Amorphophallus konkanensis Hett., S.R.Yadav & K.S.Patil | 1994 | India | |
| Amorphophallus lanuginosus Hett. | 1994 | Vietnam | |
| Amorphophallus laoticus Hett. | 2006 | Laos | |
| Amorphophallus linearis Gagnep. | 1941 | Thailand | |
| Amorphophallus longicomus Hett. & Serebryanyi | 2001 | Vietnam | |
| Amorphophallus longiconnectivus Bogner | 1995 | India (Madhya Pradesh, Maharashtra) | |
| Amorphophallus lunatus Hett. & Sizemore | 2006 | Thailand | |
| Amorphophallus macrorhizus Craib | 1912 | Thailand | |
| Amorphophallus margaritifer | 1837 | Assam, Bangladesh, East Himalaya, India, Myanmar | |
| Amorphophallus mirabilis K.Z.Hein, Naive, Serebryanyi & Hett. | 2023 | Myanmar | |
| Amorphophallus muelleri | 1837 | Assam, Borneo, Jawa, Lesser Sunda Is., Myanmar, Sumatera, Thailand | |
| Amorphophallus mysorensis | 1940 | India | |
| Amorphophallus napiger | 1941 | Cambodia, Laos, Thailand, Vietnam | |
| Amorphophallus natolii | 2012 | Philippines | |
| Amorphophallus ochroleucus | 2001 | Vietnam | |
| Amorphophallus oncophyllus | 1893 | Andaman Islands (Coco Islands) | |
| Amorphophallus operculatus | 2003 | Thailand | |
| Amorphophallus pilosus | 1994 | Vietnam | |
| Amorphophallus prolificus | 2006 | Thailand | |
| Amorphophallus putii | 1941 | Myanmar, Thailand | |
| Amorphophallus pygmaeus | 1994 | Thailand | |
| Amorphophallus reflexus | 2006 | Thailand | |
| Amorphophallus sakonnakhonensis | 2023 | Thailand | |
| Amorphophallus saururus | 2001 | Thailand | |
| Amorphophallus shyamsalilianum | 2017 | India | |
| Amorphophallus sinuatus | 2003 | Vietnam | |
| Amorphophallus sizemoreae | 2001 | Thailand. | |
| Amorphophallus sylvaticus | 1841 | India, Sri Lanka | |
| Amorphophallus symonianus | 2001 | Thailand | |
| Amorphophallus synandrifer | 2001 | Vietnam | |
| Amorphophallus thaiensis (S.Y.Hu) Hett. | 2012 | northern Thailand | |
| Amorphophallus tonkinensis Engl. & Gehrm. | 1911 | Yunnan, northern Vietnam | |
| Amorphophallus tuberculatus | 2006 | Vietnam | |
| Amorphophallus vogelianus | 2003 | Thailand | |
| Amorphophallus xiei | 2006 | China (W. Yunnan) | |
| Amorphophallus yuloensis | 1998 | China (Yunnan), Myanmar | |
| Amorphophallus yunnanensis Engl. (Kerri's giant arum) | 1911 | China, Laos, northern Thailand and Vietnam | |
| Image | Name | Year | Distribution |
|---|---|---|---|
| Amorphophallus abyssinicus | 1901 | southern Ethiopia | |
| Amorphophallus andranogidroensis | 2006 | Madagascar | |
| Amorphophallus angolensis | 1901 | Angola, Cabinda, Gabon, Sudan, Zaïre | |
| Amorphophallus ankarana | 1999 | Madagascar | |
| Amorphophallus antsingyensis | 1999 | Madagascar | |
| Amorphophallus aphyllus | 1936 | Burkina, Central African Repu, Chad, Guinea, Guinea-Bissau, Mali, Senegal, Sierra Leone, Togo | |
| Amorphophallus barthlottii | 1997 | Ivory Coast, Liberia | |
| Amorphophallus baumannii | 1901 | Benin, Burkina, Central African Repu, Chad, Gambia, Ghana, Guinea-Bissau, Liberia, Niger, Nigeria, Senegal, Sierra Leone, Togo | |
| Amorphophallus bequaertii | 1922 | Zaïre | |
| Amorphophallus calabaricus | 1901 | Benin, Cameroon, Kenya, Nigeria, Uganda, Zaïre | |
| Amorphophallus canaliculatus | 1997 | Gabon | |
| Amorphophallus consimilis | 1837 | Gambia, Senegal | |
| Amorphophallus dracontioides | 1901 | Benin, Burkina, Central African Repu, Gambia, Ghana, Ivory Coast, Niger, Nigeria, Togo | |
| Amorphophallus eichleri | 1889 | Zaïre | |
| Amorphophallus elliottii | 1894 | Sierra Leone | |
| Amorphophallus erythrorrhachis | 2014 | Madagascar | |
| Amorphophallus gallaensis | 1901 | Ethiopia, Kenya, Somalia | |
| Amorphophallus gomboczianus | 1950 | Ethiopia | |
| Amorphophallus goetzei | 1901 | Mozambique, Tanzania, Zaïre | |
| Amorphophallus gracilior | 1939 | Benin, Nigeria | |
| Amorphophallus hetterscheidii | 1997 | Central African Republic, Gabon, Zaïre | |
| Amorphophallus hildebrandtii | 1911 | Madagascar | |
| Amorphophallus impressus | 1997 | Malawi, Tanzania | |
| Amorphophallus johnsonii | 1901 | Benin, Burkina, Ghana, Guinea, Ivory Coast, Liberia, Mali | |
| Amorphophallus lewallei | 1993 | Burundi | |
| Amorphophallus mangelsdorffii | 2003 | Madagascar. | |
| Amorphophallus margretae | 1997 | Zaïre | |
| Amorphophallus maximus | 1901 | Kenya, Mozambique, Somalia, Tanzania, Zimbabwe | |
| Amorphophallus mildbraedii | 1924 | Cameroon | |
| Amorphophallus mossambicensis | 1901 | Mozambique, Tanzania, Zambia, Zaïre, Zimbabwe | |
| Amorphophallus mullendersii | 1993 | Angola, Zaïre | |
| Amorphophallus perrieri | 2014 | Madagascar. | |
| Amorphophallus preussii | 1901 | Cameroon | |
| Amorphophallus richardsiae | 1997 | Zambia | |
| Amorphophallus staudtii | 1901 | Cameroon, Congo | |
| Amorphophallus stuhlmannii | 1911 | Kenya, Tanzania, Zaïre | |
| Amorphophallus taurostigma | 1999 | Madagascar | |
| Amorphophallus teuszii | 1892 | Angola, Zaïre | |
| Amorphophallus zenkeri | 1901 | Cameroon, Gulf of Guinea Is., Nigeria | |