Nelumbo is a genus of aquatic plants with large, showy flowers. Members are commonly called lotus, though "lotus" is a name also applied to various other plants and plant groups, including the unrelated genus Lotus. Members outwardly resemble those in the family Nymphaeaceae ("water lilies"), but Nelumbo is actually very distant to Nymphaeaceae. "Nelumbo" is derived from the Sinhalese word Sinhalese: නෙළුම් neḷum, the name for the lotus Nelumbo nucifera.
Temporal range: Cretaceous–Recent
|N. nucifera (sacred lotus)|
There are only two known living species of lotus; Nelumbo nucifera is native to Asia and is better-known. It is commonly cultivated; it is eaten and used in traditional Chinese medicine. This species is the floral emblem of both India and Vietnam.
- Nelumbo lutea Willd. – American lotus (Eastern United States, Mexico, Greater Antilles, Honduras)
- Nelumbo nucifera Gaertn. – sacred or Indian lotus, also known as the Rose of India and the sacred water lily of Hinduism and Buddhism. It is the national flower of India and Vietnam. Its roots and seeds are also used widely in Asian cooking.
- †Nelumbo aureavallis Hickey – Eocene (North Dakota), described from leaves found in the Golden Valley Formation in North Dakota, USA.
- †Nelumbo changchangensis Eocene, (Hainan Island, China), described from several fossils of leaves, seedpods, and rhizomes from the Eocene-aged strata in the Changchang Basin, of Hainan Island.
- †Nelumbo minima Pliocene (Netherlands), described from leaves and seedpods that suggest a very small plant. Originally described as a member of the genus Nelumbites, as "Nelumbites minimus."
- †Nelumbo nipponica Eocene-Miocene, fossil leaves are known from Eocene-aged strata in Japan, and Miocene-aged strata in Russia.
- †Nelumbo orientalis Cretaceous (Japan), one of the oldest known species, fossils are found in Cretaceous-aged strata of Japan.
- †Nelumbo protolutea Eocene (Mississippi), fossils of leaves strongly suggest a plant similar in form to the American lotus.
There is residual disagreement over which family the genus should be placed in. Traditional classification systems recognized Nelumbo as part of the Nymphaeaceae, but traditional taxonomists were likely misled by convergent evolution associated with an evolutionary shift from a terrestrial to an aquatic lifestyle. In the older classification systems it was recognized under the biological order Nymphaeales or Nelumbonales. Nelumbo is currently recognized as a only living genus in Nelumbonaceae, one of several distinctive families in the eudicot order of the Proteales. Its closest living relatives, the (Proteaceae and Platanaceae), are shrubs or trees.
The leaves of Nelumbo can be distinguished from those of genera in the Nymphaeaceae as they are peltate, that is they have fully circular leaves. Nymphaea, on the other hand, has a single characteristic notch from the edge in to the center of the lily pad. The seedpod of Nelumbo is very distinctive.
Earlier classification systemsEdit
The Cronquist system of 1981 recognizes the family but places it in the water lily order Nymphaeales. The Dahlgren system of 1985 and Thorne system of 1992 both recognize the family and place it in its own order, Nelumbonales.
Nelumbo nucifera regulates its temperature in order to benefit insect pollinators. When the plant flowers, it heats its blossoms to above 30 °C (86 °F) for as long as four days even when the air is as cool as 10 °C (50 °F). The heat releases an aroma that attracts certain insects, which fly into the flower to feed on nectar and pollen. According to Roger Seymour and Paul Schultze-Motel of Australia’s University of Adelaide, the heat also rewards insects with a stable environment that enhances their ability to eat, mate, and prepare for flight.
The sacred lotus, N. nucifera, is sacred in both Hinduism and Buddhism.
- Hyam, R. & Pankhurst, R.J. (1995). Plants and their names : a concise dictionary. Oxford: Oxford University Press. ISBN 978-0-19-866189-4.
- "Nelumbo nucifera (sacred lotus)". Kew. Retrieved 26 July 2015.
- Hickey, Leo (1977). Stratigraphy and Paleobotany of the Golden Valley Formation (Early Tertiary) of Western North Dakota. Boulder, Colorado: Geological Society of America. pp. 110 & Plate 5. ISBN 0-8137-1150-9.
- Angiosperm Phylogeny Group (2016). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG IV" (PDF). Botanical Journal of the Linnean Society. 181 (1): 1–20. ISSN 0024-4074. doi:10.1111/boj.12385.
- Darmanin, Thierry; Guittard, Frédéric (1 June 2015). "Superhydrophobic and superoleophobic properties in nature". Materials Today. 18 (5): 273–285. doi:10.1016/j.mattod.2015.01.001.
- "Heat of Lotus Attracts Insects And Scientists". New York Times. 1996-10-01.