Retispatha

Retispatha dumetosa is an endemic to Borneo palm. It is the only species of the genus Retispatha. The leaf sheaths, petioles and rachis are densely reinforced.

• 4.1 Notes and references

Features

Retispatha dumetosa is an upright or short climbing palm. It is reinforced, multi- flowering and dioecious getrenntgeschlechtig ( dioecious ). The stem is bare with time, wearing conspicuous scars at the nodes, has rather short internodes. In the lower part of the stem are short, brut onion-like shoots. At the lower node set numerous adventitious roots.

The number of chromosomes is not known.

The leaves are pinnate and bear no tendril. The leaf sheath is Roehrig, densely covered with slender spines that are arranged in whorls or Teilwirteln. They are also densely hairy. A Ochrea missing as well as a knee. The petiole is clearly trained and also reinforced tight. The rachis is covered with backward thorns that are in groups of up to five. The leaflets are numerous and are in a regular arrangement. You are folded once, linear and occupied at the edges and main nerves with bristles.

Inflorescences

The inflorescences are in the leaf axils, but are fused with the internode and the leaf sheath of the next sheet. They are initially upright, later suspended. Male and female inflorescences are similar, but the male branches are up to three times, the female only simple, rarely twice. The cover sheet is large, Roehrig, then torn in the bottom half. It is densely covered with black spines that are Teilwirteln. Bracts on the inflorescence stem missing. The bracts of the inflorescence axis similar to the previous sheet. The first-order lateral axes hanging in the heyday down and carry them in two rows imbricate, unreinforced bracts that are Roehrig in the lower two thirds. They have a triangular edge that consists of dense, criss-crossing fibers, and including a kitten -like, gathered, branching system in the male inflorescences. Each side of the axis of the second order is in the armpit of a triangular, membranous, ciliated on the edge, high -tube sheet. The side axes of the third order, the Rachillae wearing membranous, ciliate -tube bracts, each one zweikielige, ciliated, Brakteole -tube and a single male flower -supporting.

In the female inflorescences, the flower-bearing axes Rachillae are mostly located on the major axis, rarely at a sometimes existing basal standing side branch. The bracts of Rachillae are two lines ( distich ), are imbricat and similar reticulate as in the male inflorescences. The Rachillae are mostly hidden by the bracts and carry up to 20 distiche, tubed and ciliated bracts, each of which carries a zweikieliges cover page, a tubed Brakteole and a female flower.

Flowers

The male flowers are very small and symmetrical. The cup is Roehrig with three triangular lobes, the tips of which are hairy. The crown is about twice as long as the Klech in the bud. It is only at the base Roehrig, the three lobes are striped and valvat. At the height of the receptaculum extended, so that the crown appears Roehrig in the lower third. The six stamens are free from the crown in the bud. The filaments are laterally interconnected. The anthers are oblong to oval, dorsifix near the base and latrors. The stamp rudiment is in three parts and very small. The pollen is ellipsoidal and bisymmetrical. The colpi are in equatorial positions and are disulcat.

The female flowers are much larger than the male. The cup is Roehrig with three short, triangular lobes. He rips open after flowering. The crown is Roehrig and slightly shorter than the calyx. She has three short, valvate lobes and also tears down. The filaments of the six staminodes form a short tube, the empty anthers are flat. The gynoecium is incomplete dreifächrig with three ovules. It is egg-shaped, scaly and bears three stigmas, which are flashy and fleshy, and are on a non- scaly stylus. The ovule is basal and anatrop.

Fruits

The fruit is one seed and partially obscured by the net-like bracts. It is ovoid to slightly inverted pear-shaped. She's beaked with an apical scar remaining. Eas exocarp is busy with vertical rows of downward-facing shed. The mesocarp is thin, a endocarp is not differentiated. The seed is basally and has a thin, sweet Sarko Testa.

Dissemination and locations

Retispatha dumetosa is an endemic plant species in Borneo. It is known only from scattered locations throughout the island of time. It forms thickets on slopes and valley floors in dipterocarp forests. You lack in mountain and heath forests. Although it is widespread, it is still rare.

System

The genus Retispatha is placed in the subfamily Calamoideae, Tribe and subtribe Calameae Calaminae within the family Arecaceae.

In the World Checklist of Selected Plant Families of the Royal Botanic Gardens ( Kew ), only the type Retispatha dumetosa is recognized.

The name comes from the Latin word rete Network and the Greek spathe for bract and refers to the net-like bracts in the inflorescences.

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. 197f.