Plectocomia

Plectocomia elongata

Plectocomia is a native of Asia, climbing palm species. The inflorescences have long pendulous lateral axes of the first order, the individual flower-bearing lateral axes of the second order are surrounded by showy, boat-shaped bracts.

  • 5.1 Notes and references

Features

The representatives are multi-stemmed, high climbing Rattanpalmen. You are hapaxanth and dioecious. The tribe has long internodes and noticeable scars. In the lower part of the internodes sometimes sit numerous Bulbillenartige rung. After incision of the strain exuded this clear rubber juice. The trunk has a soft paste, which is why the species are not used for rattan furniture.

The chromosome number is unknown ( as of 2008).

The leaves of adult palms are large, pinnate and have a tendril. The leaf sheath is reinforced Roehrig and to different degrees. A Ochrea missing. The petiole may be absent. He as the lower part of the rachis are deeply grooved and varies greatly reinforced. The vine and the upper part of the rachis are regularly occupied by groups of large, backward- directed spines. The numerous leaflets are simply folded, entire, usually lanceolate.

Inflorescences

The inflorescences are formed simultaneously in the axils of two to 20 distal, often reduced leaves. The inflorescence axis is significantly longer than the peduncle. The bracts of the inflorescence axis are distich ( two rows ), each carrying a suspended lateral axis of the first order. From these, there are three to 20, more rarely. Each has a basal, röhriges zweikieliges cover page and one or more empty -tube bracts. The remaining bracts are very conspicuous. You are distich, are initially Roehrig and tear before flowering along on almost to the top. They enclose some or all of the Rachilla ( flower-bearing axis). The bracts are thin teilverholzt until very thick, leathery or. The Rachillae are unbranched, slender and bear in female inflorescences two to ten flowers, in male two to about 100 The male groups are sometimes in distinct groups of two ( dyads ), often the arrangement in dyads through crowded stand together and long inflorescences is superimposed.

Flowers

The male flowers have a short -tubular calyx with three short lobes. The crown is at the bottom of Roehrig and has three triangular to lanceolate lobes. The most six, rarely twelve stamens are sometimes fused basally with their stamens. They stand at the mouth of the corolla tube. The anthers are usually long. The stamp rudiment is very small or absent. The pollen is ellipsoidal and bisymmetrical, the seed openings are bisulcat equatorial. The longest axis measures 26-49 microns.

The female flowers appear singly, are often stalked with a zweikieligen Brakteole on a stick. The calyx is short tubular and has three short to very long lobes. The crown is also Roehrig and has three narrow to broad triangular lobes. The crown is something much longer than the calyx up. The six staminodes have flat stamens and anthers empty. The gynoecium is round, covered with scales, usually has three long scars and sometimes a very pronounced pen. The three fruit trays are incomplete, have three ovules sitting basal and are anatrop.

Fruit and seeds

The fruit is usually one seed, rarely two or dreisamig. The exocarp is busy with vertical rows of backward shed. The scales peaks often point upwards. The mesocarp is thin and fibrous, endocarp is not differentiated. The seed sits near the base, the sarcotesta is thick, but not juicy. The endosperm is homogeneous.

Ecology

As a visitor to the heavily scented male flowers of Plectocomia fell off diana bees and beetles ( Nitidulidae, Staphylinidae ) were observed. About the fruit spread is not known.

Dissemination and locations

The area extends from the Himalayas, southern China and Hainan Burma and Indochina to Sundaschelf and the Philippines. East of the Wallace Line is the genus not before.

The most common and best known species elongata and Plectocomia Plectocomia mulleri. Both grow from sea level to 2000 m above sea level. The former grows mostly in disturbed habitats on poor soils, the latter also in swamp forests and heath forests ( Kerangas ).

System

The genus Plectocomia is placed in the subfamily Calamoideae, Tribe Calameae within the family Arecaceae. They, together with the genera Myrialepis and Plectocomiopsis the subtribe Plectocomiinae. The relationships between the three genera are unclear. Plectocomia is monophyletic.

In the World Checklist of Selected Plant Families of the Royal Botanic Gardens, Kew, the following types are recognized:

  • Plectocomia assamica
  • Plectocomia billitonensis
  • Plectocomia bractealis
  • Plectocomia fell off diana
  • Plectocomia elmeri
  • Plectocomia elongata
  • Plectocomia himalayana
  • Plectocomia khasyana
  • Plectocomia longistigma
  • Plectocomia lorzingii
  • Plectocomia macrostachya
  • Plectocomia microstachys
  • Plectocomia mulleri
  • Plectocomia pierreana
  • Plectocomia pygmaea

Documents

  • John Dransfield, Natalie W. Uhl, Conny B. Asmussen, William J. Baker, Madeline M. Harley, Carl E. Lewis: Genera palmarum. The Evolution and Classification of Palms. Second edition, Royal Botanic Gardens, Kew 2008, ISBN 978-1-84246-182-2, pp. 182-185.
Carl Ludwig Blume Stigma (botany)
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