Porphyrostachys

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Porphyrostachys
Systematics
Order : Asparagales (Asparagales)
Family : Orchids (orchidaceae)
Subfamily : Orchidoideae
Tribe : Cranichideae
Sub tribus : Cranichidinae
Genre : Porphyrostachys
Scientific name
Porphyrostachys
Rchb.f.

Porphyrostachys is a genus from the family of the orchid (Orchidaceae). It consists of only two types of herbaceous plants that are native to the Andes of South America.

description

The two species of the genus Porphyrostachys are terrestrial herbaceous plants, they can reach heights of up to 80 centimeters. The roots , which arise in clusters, are fleshy, hairy and thickened in a spindle-shaped manner. The leaves are in a basal rosette, they are clearly stalked. Their shape is oval, they are not present at flowering time.

The grape-like, dense with numerous flowers occupied inflorescence is terminal. It is erect, hairless and has translucent, paper-like bracts . The bracts are about as long as the ovary or a little longer. The ovary is sessile and in Porphyrostachys pilifera angular in cross section. The flowers are not resupinated and have a striking reddish color. The dorsal sepal is turned back or turned back spirally. The lateral sepals are asymmetrical, turned back or bent back, fused together at the bottom and running down a little at the ovary. The petals are linear and twisted in a spiral. The lip is somewhat deepened and shell-shaped, abruptly narrowed (nailed) at the base, there fused with the descending column base. Together with the lateral sepals, the base of the lip forms a tubular nectarium . The column is elongated and slender, finely to warty hairy, at the base protruding far beyond the point of attachment at the ovary (columnar foot). The scar consists of two surfaces that are roughly parallel and approach each other under the rostellum . The separating tissue between the stamen and stigma (rostellum) is short and rounded, it ends with incisions. The stamen is oval to lanceolate, it contains the club-shaped pollinia .

Dressler suspects hummingbirds as flower visitors due to the color and shape of the flowers .

Occurrence

Porphyrostachys occurs in the Andes of South America in Ecuador and Peru. Altitudes from 1600 to 3000 meters are populated. The locations are in open, little shaded areas in grassland.

Systematics and botanical history

The genus Porphyrostachys was described by Heinrich Gustav Reichenbach in 1854 . The name is made up of the Greek words πορφύρεος porphyreos , "purple", and στάχυς stachys , "ear". It relates to the color of the flowers. The type species is Porphyrostachys pilifera , known as Altensteinia pilifera even before Reichenbach's description of the new genus .

Porphyrostachys is classified within the tribe Cranichideae in the subtribe Cranichidinae . The genera Aa and Myrosmodes are closely related .

The following types are known:

See also

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. 173 .
  • Alec M. Pridgeon, Phillip Cribb, Mark W. Chase, Finn Rasmussen (Eds.): Genera Orchidacearum. Orchidoideae (Part 2). Vanilloideae . tape 3 . Oxford University Press, New York / Oxford 2003, ISBN 0-19-850711-9 .

Individual evidence

  1. ↑ a b c Jeffrey Wood: Porphyrostachys . In: Genera Orchidacearum . Vol. 3, p. 47.
  2. ↑ Leslie Garay: Porphyrostachys . In: Flora of Ecuador . Vol. 9, p. 211.
  3. ^ Robert L. Dressler: The orchids: natural history and classification . Harvard University Press, Cambridge, Massachusetts 1981.
  4. ↑ a b c d e Rafaël Govaerts (Ed.): Porphyrostachys. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved July 18, 2018.
  5. ↑ Gerardo A. Salazar, Lidia I. Cabrera, Santiago Madriñán, Mark W. Chase: Phylogenetic relationships of Cranichidinae and Prescottiinae (Orchidaceae, Cranichideae) inferred from plastid and nuclear DNA sequences . In: Annals of Botany . tape 104 , 2009, p. 403-416 , doi : 10.1093 / aob / mcn257 .

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