Microchilus (orchids)

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Microchilus
Microchilus arietinus

Microchilus arietinus

Systematics
Order : Asparagales (Asparagales)
Family : Orchids (orchidaceae)
Subfamily : Orchidoideae
Tribe : Cranichideae
Sub tribus : Goodyerinae
Genre : Microchilus
Scientific name
Microchilus
C. Presl

Microchilus is a genus from the family of the orchid (Orchidaceae). It consists of about 164 species of herbaceous plants native to tropical America.

description

The species of the genus Microchilus form a creeping rhizome that is rooted at the nodes . The rising shoots carry the leaves evenly distributed or in a loose rosette, roughly in the lower half of the upright shoot. The leaves are broad to narrowly oval in shape, often somewhat asymmetrical, with short stalk. The tubular leaf base includes the shoot. The color of the leaves is green to brownish, sometimes with light green or silver markings.

The stem axis continues above the leaves as a multi-flowered, racemose inflorescence . The inflorescence axis is hairy and is surrounded by a few bracts . The bracts are about as long as ovary and pedicel together. The ovary is hairy and twisted, the flowers are resupinated . The petals are free. The three sepals are roughly the same shape and size, hairy on the outside of some species. The lateral sepals are spread apart, the upper sepal forms a tube with the lateral petals attached to it . The lateral petals are narrowly linear to oblong-lanceolate, broadest above the middle. The lip forms a long, cylindrical to oval spur at the base, rarely bilobed at the end. In the interior of the spur there are usually low lamellae. The lip is divided into two parts: the basal part, the hypochil, is U-shaped in cross-section and only rarely has lamellae inside. The front part, the epichil, has entire margins or ends with two lobes. The column is spindle-shaped, its lower part is fused with the edges of the lip. The stamen contains two club-shaped pollinia , each of which is connected to the adhesive disc (Viscidium) by a small stalk. The stigma consists of an undivided area that lies beneath the separating tissue between the stigma and the stamen (rostellum). The rostellum is long triangular with a two-part tip.

distribution

Microchilus is common in tropical America. The area extends from Mexico and the Bahamas in the north over Central America and the Caribbean over all of South America to about the level of the Río de la Plata in the south. The species grow in evergreen forests, occasionally also epiphytically . They occur at altitudes up to 2000 meters.

Systematics and botanical history

The genus Microchilus was established in 1827 by Karl Bořiwog Presl . Type species is Microchilus minor . The name Microchilus is derived from the Greek μικρός mikros , "small", and χεῖλος cheilos , "lip", it refers to the small petal called lip. The species have long been listed in the genus Erythrodes together with very similar plants from Southeast Asia . Microchilus is classified within the tribe Cranichideae in the subtribe Goodyerinae . According to Dressler, this can be further divided into two groups; Dressler puts it under the name Erythrodes together with the majority of the genera that do not have two clearly separated areas of scarring.

Illustration of Microchilus austrobrasiliensis , Fig. II, right
Illustration of Microchilus tridax

While 40 species in the genus Microchilus were counted in the work "Genera Orchidacearum", according to studies by Paul Ormerod , the number increased considerably between 2000 and 2010 and is now around 164 species:

See also

literature

  • 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 , pp. 121-124 .
  • Paul Ormerod: Studies of neotropical Goodyerinae (Orchidaceae) . In: Harvard Papers in Botany . tape 9 , no. 2 , 2005, p. 391-423 .
  • Paul Ormerod: Studies of neotropical Goodyerinae (Orchidaceae) 2 . In: Harvard Papers in Botany . tape 11 , no. 2 , 2007, p. 145-177 .
  • Paul Ormerod: Studies of neotropical Goodyerinae (Orchidaceae) 3 . In: Harvard Papers in Botany . tape 13 , no. 1 , 2008, p. 55-87 .
  • Paul Ormerod: Studies of neotropical Goodyerinae (Orchidaceae) 4 . In: Harvard Papers in Botany . tape 14 , no. 2 , 2009, p. 111-128 .
  • Paul Ormerod: Notulae Goodyerinae (IV) . In: Taiwania . tape 54 , no. 1 , 2009, p. 45-51 .

Individual evidence

  1. ↑ a b c d e 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 , pp. 121-124 .
  2. ^ Robert L. Dressler: Phylogeny and Classification of the Orchid Family . Cambridge University Press, Cambridge 1993, ISBN 0-521-45058-6 , pp. 118 .
  3. ↑ a b c d e f g h i j k l m n o p q r s t Rafaël Govaerts (Ed.): Microchilus. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved March 27, 2020.

Web links

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