Myrialepis paradoxa
| Myrialepis paradoxa | ||||||||||||
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Myrialepis paradoxa |
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Myrialepis | ||||||||||||
| Becc. | ||||||||||||
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| Myrialepis paradoxa | ||||||||||||
| ( Short ) J.Dransf. |
Myrialepis paradoxa is a climbing palm species native to Asia. It is the only representative of the genus Myrialepis . The flowers are - unusual in palms - individually on the inflorescence axes.
features
The representatives are multi-stemmed, high-climbing reinforced rattan palms. They are hapaxanth and diocesan . The trunk has long internodes and noticeable scars. Basal vegetative side axes arise opposite the leaves.
The number of chromosomes is unknown (as of 2008).
leaves
The leaves of adult palm trees are large, pinnate and have a tendril . The leaf sheath is Roehrig. Knees or ochrea are not trained. The petiole is very short to long and deeply furrowed. The rachis is hardly reinforced proximally like the stalk, distally more strongly reinforced with regular groups of grappling hook-like spines. The numerous leaflets are lanceolate, with entire margins, sometimes reinforced with short marginal spines.
Inflorescences
The inflorescences are formed at the same time in the axils of the most distal, often reduced leaves. There are three orders of inflorescence axes. The inflorescence stalk is short, the cover sheet is tubular, two-keeled with two triangular lobes and hidden in the leaf sheath. Bracts on the peduncle are missing. The inflorescence axis is much longer than the stalk. Their bracts are tubular, almost two-lined (distich), each has a lateral axis. The flower-bearing rachillae are very short and are formed by axes of different orders. Male rachillae have groups of up to eight flowers, female rachillae have groups of two to seven flowers.
blossoms
The male flowers are symmetrical. The chalice is membranous, tubular and has three lobes. The crown is membranous and divided into three triangular lobes almost to the base. The six stamens are at the base of the corolla lobes. The pollen is ellipsoidal and bisymmetrical. The longest axis measures 31 to 38 microns.
The female flowers are larger than the male. The chalice is membranous, tubular with three lobes. The crown is membranous, divided into three lobes almost to the base. There is a staminode ring at the base of the crown . The gynoeceum is incompletely triple with three ovules . It is spherical and covered with small scales. The three scars are short and apical. The ovules are basal and anatropic.
Fruits and seeds
The fruit is solitary, the flower shell remains on the fruit, the remnants of the stigma are very small. The exocarp is covered with very small, irregularly standing scales. The mesocarp is thin and fibrous. The endocarp is not differentiated. The seed stands at the base, its sarcotesta is thick but not juicy. The endosperm is homogeneous.
Distribution and locations
Myrialepis paradoxa occurs in Indochina, Burma, Thailand, the Malay Peninsula and Sumatra. It grows from sea level to around 1000 m above sea level. It is widespread and often forms thickets. Like the other hapaxanthene rattan palms, it is found preferentially in disturbed locations in primary forests.
Systematics
The genus Myrialepis Becc. is placed within the family Arecaceae in the subfamily Calamoideae , tribe Calameae . Together with the genera Plectocomia and Plectocomiopsis, it forms the subtribe Plectocomiinae . The relationships between the three genera are unclear.
In the World Checklist of Selected Plant Families of the Royal Botanic Gardens, Kew, only the species Myrialepis paradoxa (short) J.Dransf. accepted.
supporting 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. 186-188.
Individual evidence
- ↑ Rafaël Govaerts (ed.): Myrialepis. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved March 26, 2010.
Web links
- Myrialepis on the homepage of the Fairchild Tropical Botanic Garden