Palm orchids

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Palm orchids
Illustration of Palm Orchis pubescentis (as a synonym Rolfea elata)

Illustration of Palm Orchis pubescentis
(as a synonym Rolfea elata )

Systematics
Monocots
Order : Asparagales (Asparagales)
Family : Orchids (orchidaceae)
Subfamily : Epidendroideae
Tribe : Neottieae
Genre : Palm orchids
Scientific name
Palm orchids
Barb.Rodr.

The genus palmorchis from the family of the orchid (Orchidaceae) consists of 21 species . They occur in tropical South and Central America.

description

The palm orchid species are herbaceous plants that are occasionally woody at the base and up to one meter high. They grow terrestrially, Palmorchis imuyanensis also semi-aquatic . The roots stand together in clusters and are fleshy, but not thickened. The shoot is thin, upright, leafed in the upper area. The leaves are short-stalked, oval, ending in a pointed to elongated manner. They are pleated (plicate) along the leaf veins.

The flowers of a population often appear simultaneously and are only short-lived. The racemose or branched inflorescences can only appear terminally, only in the leaf axils or both combined. The bracts of the flowers are folded along the midrib (konduplikat). The small flowers are resupinated , the petals form a tube, but are not fused together. Except for the lip , the petals are shaped similarly to each other, the petals are slightly shorter and narrower than the outer petals. The lip is fused with the column at the base . It is three-lobed, the side lobes stand upright, parallel to the column or enclose it. The middle lobe is much smaller, the blade is covered with ridges or warts. The column is slender and curved. The stamen at the end of the column is bent down towards the column axis. It is hardly covered by the tissue of the column. It contains four pear-shaped pollinia , the cohesion of the pollen is not particularly firm, but the consistency is not floury either. The pollinia have neither stalks nor glutinous glands. The scar is oval in shape and lies across the axis of the column; it is surrounded by a raised edge. The separating tissue between the stigma and the stamen (rostellum) is only short. The capsule fruit is fleshy, the column sticks to the fruit until it is ripe. In contrast to most other orchids, the seeds have a hard seed coat .

distribution

The species of the genus Palmorchis are common in tropical South America. In the north the area extends to Central America and reaches Costa Rica and Nicaragua. In the south the area extends roughly to the Amazon. Forests are populated up to altitudes of 1000 meters.

ecology

It has been observed that three species of palm orchid from Panama are visited by bees of the genera Osiris and Trigona . An actual pollination by Osiris could be proven in Palmorchis nitida .

The fleshy fruits and the hard seed coat could indicate an endozoochore spread.

Systematics and botanical history

The classification of the genus Palmorchis within the subfamily Epidendroideae has long been unclear. Sobralia and Elleanthus , Diceratostele or, based on comparable seeds, vanilla have been suggested as related genera . Dressler arranged them in their own tribe , the Palmorchideae. According to recent DNA studies, it is counted to the tribe Neottieae . It is probably the sister group of all other Neottieae; alternatively, the palm orchid line could branch off before the Neottieae:

Palm orchids as a sister group of the Neottieae Palmorchis as a sister group of the Epidendroideae



Palm orchids


   

remaining Neottieae



   

remaining Epidendroideae



Template: Klade / Maintenance / Style


Palm orchids


   

Neottieae


   

remaining Epidendroideae




Template: Klade / Maintenance / Style

The genus was described by João Barbosa Rodrigues in 1877 . The lectotype is Palm Orchis pubescentis . The name Palmorchis refers to the similarity of the plants to palms of the genus Geonoma .

37 valid species are now known:

literature

  • Leslie A. Garay: 225 (1). Orchidaceae (Cypripedioideae, Orchidoideae and Neottioideae) . In: Gunnar Harling, Benkt Sparre (ed.): Flora of Ecuador . tape 9 , 1978, ISSN  0347-8742 , p. 141 .
  • Alec M. Pridgeon, Phillip Cribb, Mark W. Chase (Eds.): Genera Orchidacearum. Epidendroideae (Part one) . 2nd Edition. tape 4 . Oxford University Press, New York and Oxford 2005, ISBN 0-19-850712-7 .
  • Charles Schweinfurth, Donovan S. Correll: The Genus Palmorchis . In: Botanical Museum Leaflets, Harvard University . tape 8 , no. 6 . Cambridge, Massachusetts 1940, p. 109 ( botanicus.org ).

Individual evidence

  1. ^ A b c Robert L. Dressler: Phylogeny and Classification of the Orchid Family . Cambridge University Press, 1993, ISBN 0-521-45058-6 , pp. 103-104 .
  2. ↑ a b c d Erik Paul Rothacker: The primitive Epidendroideae (Orchidaceae): phylogeny, character evolution and the systematics of Psilochilus (Triphoreae). (pdf) Ohio State University, 2007, accessed December 19, 2009 .
  3. ↑ Leslie Garay: Palm Orchis . In: Orchidaceae (Cypripedioideae, Orchidoideae and Neottioideae) . P. 141.
  4. ↑ a b Jeffrey Wood: Palm Orchis . In: Genera Orchidacearum . Vol. 4, pp. 513-515.
  5. ↑ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am Rafaël Govaerts (Ed.): Palmorchis. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved April 9, 2020.
  6. ↑ Nelis A. Cingel: An atlas of orchid pollination: America, Africa, Asia and Australia . CRC Press, 2001, ISBN 978-90-5410-486-5 , pp. 78 .

Further information

Web links

Commons : Palmorchis  - album with pictures, videos and audio files