Neottia

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Neottia
Neottia cordata (syn. Listera cordata)
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Epidendroideae
Tribe: Neottieae
Genus: Neottia
Guett.[1]
Species

About 70; see text

Synonyms[2]

Listera R.Br.

Neottia is a genus of orchids. The genus now includes the former genus Listera, commonly known as twayblades referring to the single pair of opposite leaves at the base of the flowering stem. The genus is native to cooler temperate and subarctic regions throughout the Northern Hemisphere, including the Arctic.[1] They produce racemose inflorescences with flowers in shades of green or dull pink through to maroon and purple. The lip of each flower is prominently forked or two-lobed. Some species (those which were previously the only members of the genus Neottia, such as the bird's-nest orchid, Neottia nidus-avis) are completely without chlorophyll and have leaves which are reduced to scales.

N. nidus-avis, a non-photosynthetic species

Description[edit]

Neottia is a genus of relatively small terrestrial orchids. Some (the former genus Listera) have chlorophyll and are hence gaining their energy from photosynthesis. Others (the formerly narrowly defined genus Neottia) lack chlorophyll and are dependent on fungi for their nutrition (mycotrophic). The flowering stem has a number of greenish or brownish bracts at the base. In the photosynthetic members of the genus there are also two more-or-less opposite green leaves (very rarely more than two in Neottia ovata). The flowers are individually small, in shades of green, yellow, brown or red to purple. The lip is usually much larger than the other five tepals, and is almost always deeply divided into two lobes at the end.[3] The other five tepals may form a loose hood.[4] The pollinia are not stalked.[3]

Taxonomy[edit]

At one time the genus was divided between Neottia and Listera. Molecular phylogenetic studies in this century have shown that the species lacking chlorophyll, such as Neottia nidus-avis, evolved from within the group with chlorophyll,[4] so that the two genera Neottia and Listera should be combined. As Neottia is the older name, sources such as the World Checklist of Selected Plant Families and the Flora of China now use Neottia for all species formerly in Listera.[2] Other sources continue to divide the genus into two.[5]

Species[edit]

There are about 70 species, mainly distributed in eastern and northern Asia, Europe and North America. A few are found in tropical Asia.[3] Species include:

References[edit]

  1. ^ a b "Neottia", World Checklist of Selected Plant Families, Royal Botanic Gardens, Kew, retrieved 2012-04-05 
  2. ^ a b "Listera", World Checklist of Selected Plant Families, Royal Botanic Gardens, Kew, retrieved 2012-04-04 
  3. ^ a b c Chen, Xinqi; Gale, Stephan W.; Cribb, Phillip J., "Neottia", retrieved 2012-04-05 , in Wu, Zhengyi; Raven, Peter H. & Hong, Deyuan, eds. (1994 onwards), Flora of China, Beijing; St. Louis: Science Press; Missouri Botanical Garden, retrieved 2012-04-05 
  4. ^ a b c d e Stace, Clive (2010), New Flora of the British Isles (3rd ed.), Cambridge, UK: Cambridge University Press, ISBN 978-0-521-70772-5 , p. 864
  5. ^ a b c d e f g h i "Plants Profile for Listera (twayblade)", USDA Plants, USDA Natural Resources Conservation Service, retrieved 2012-04-05  (former Listera only)

External links[edit]