Pholidocarpus
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Pholidocarpus is a genus of palm native to Southeast Asia.
features
The representatives are large, single-stemmed, hermaphrodite fan palms . They are reinforced and bloom several times. The trunk is erect and covered with inconspicuous, ring-shaped leaf scars. The palm trees can be very high at 45 m.
The number of chromosomes is not known.
leaves
The leaves are folded induplicat and costapalmat. In young plants, the leaves are marzescent, so they remain on the plant after they have died. In palms with a well-developed trunk, the leaves fall off under their own weight after they have died. The leaf sheath breaks down into a mass of interwoven, reddish-brown fibers. The petiole is long, strong and hairy. It is slightly furrowed on the top, rounded or angular on the underside. The edges of the stem are covered with strong, horizontal spines. The adaxial hastula is well developed, triangular, ring-like, the abaxial hastula is inconspicuous or absent.
The leaf blade is divided along the adaxial folding edges almost to the hastula, so that three to four-fold segments arise. These segments are further subdivided along the adaxial fold edges to two thirds to one half of the sheet radius, so that simply folded sub-segments arise.
Inflorescences
The inflorescences are between the leaves (interfoliar). They grow out of the mouth of the leaf sheath and protrude arched from the crown. Up to five leaf axils form inflorescences at the same time. They are fourfold. The peduncle is strong. The cover sheet is tubular, two-keeled and slightly inflated. There are one to five bracts on the peduncle. These are strong, tubular and tear irregularly with age. The inflorescence axis is longer than the stem. Here the bracts are rather distant, each bearing a side branch of the first order. The flower-bearing axes (rachillae) are bald or hairy, rather protruding, and carry the flowers in a spiral arrangement. The flowers stand alone or in pairs or threes on low elevations. They stand in the armpits of small, triangular bracts and each have a small bracteole.
blossoms
The flowers are hermaphrodite, sessile and golden yellow. The calyx is cup-shaped, flat three-lobed and glabrous to slightly hairy. The crown is divided into three triangular, valvate , bald to slightly hairy tips almost to the base . There are six stamens , the filaments of which are connected to form a conspicuous tube, but not connected to the crown. The tube is flat with six lobes, with short, slender free filaments at the end, on which there are rather round to elongated, dorsifixe and latrorse anthers . The gynoeceum consists of three carpels and is clearly conical, hairy. The fruit leaves are basal free apical but at a long, slender stylus grown. The scar is punctiform. The ovule is basal and anatropic.
The pollen is ellipsoidal, and symmetrical or slightly asymmetrical. The germ opening is a distal sulcus.
Fruits and seeds
The fruit develops from a carpel. It is very big and spherical. The scar remains are apical, but are hardly visible. The pericarp is massive: the exocarp is smooth or disintegrated into numerous, low brown cork warts. The mesocarp is thick, rather fleshy and often streaked with fibers running radially. The endocarp is crusty. The seed attaches to the side or near the base. It has a massive, homogeneous endosperm . On one side, however, the endosperm is pressed in by a large indentation in the seed coat. The embryo is roughly basal or lateral.
Distribution and locations
The genus occurs only in Southeast Asia. The distribution area extends from southern Thailand over the Malay Peninsula to Sumatra, Borneo, Sulawesi and the Moluccas . On the Malay Peninsula, Sumatra, and Borneo, the species represent striking lowland palm trees that are often found in freshwater and peat swamp forests. They are seldom found on non-wet soils.
Systematics
The genus Pholidocarpus flower is placed within the family Arecaceae in the subfamily Coryphoideae , Tribus Trachycarpeae , Subtribus Livistoninae . The monophyly of the genus has not yet been investigated. Pholidocarpus is possibly the sister group of Johannesteijsmannia .
In the World Checklist of Selected Plant Families of the Royal Botanic Gardens, Kew , the following types are recognized:
- Pholidocarpus ihur (Giseke) flower : It occurs from northern Sulawesi to Maluku .
- Pholidocarpus kingianus (Becc.) Ridl. : It occurs on the Malay Peninsula.
- Pholidocarpus macrocarpus Becc. : It occurs from Thailand to Sumatra.
- Pholidocarpus majadum Becc. : It only occurs in Borneo.
- Pholidocarpus mucronatus Becc. : It only occurs in western Sumatra.
- Pholidocarpus sumatranus Becc. : It only occurs in western Sumatra.
Pholidocarpus was first described by Carl Ludwig Blume in 1830 , the type species is Pholidocarpus ihur . The generic name is derived from the ancient Greek words for scales and fruit and refers to the corky, warty fruits of most species.
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. 268-270.
Individual evidence
- ↑ Rafaël Govaerts (ed.): Pholidocarpus. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved March 20, 2012.