Synechanthus

Synechanthus is an American palm genus. Their representatives are moderately large palm trees in the understory of forests. They are common ornamental plants.

• 4.1 Notes and references

Features

Synechanthus is a moderately large, single -stemmed or clump-forming, non-reinforced palm with pinnate leaves. They bloom several times, are monoecious, and sometimes bloom already, while they are still stemless. The stem is slender, usually erect, rarely lie down, smooth and shiny or dark yellowish to olive green. The trunk is filled with clear, away standing leaf scars.

The chromosome number is 2n = 32

The leaves are pinnate reduplicat. The leaf sheath is long in young leaves, but tear very early on compared to the petiole. The radicals are differentiated from the stem by a narrow, usually fibrous, dry strip along the edge. The petiole is circular in cross section. The rachis is oberseits edged, rounded at hand. The leaflets are at the insertion of wide reduplicat until several main veins that protrude with one at the top. Sometimes the leaf blade is undivided, then at the head of two parts ( bifid ).

Inflorescences

The inflorescences are between or among the leaves. You are branched with single or double. At the height to stand upright, crop maturity, they are bent or hanging. The peduncle is long. The cover sheet is short, Roehrig, the stem comprising a watershed and ultimately disintegrating into fibers. There are four or five bracts on the inflorescence stalk, similar to the previous sheet, but are longer. Put you in ever greater distances to each other. The last bract protrudes beyond the peduncle. The inflorescence axis is usually long. The flower-bearing axes ( Rachillae ) are slender, about the same length, square flattened to clear and flexible. Your tips are even slimmer and almost prickly.

Flowers

The flowers are usually in distich arranged coiling. A winding consists of a proximal female flower and 5 to 13 distal, biseriaten male flowers. On winding the distal flower opens first, the further opening occurs basipetally.

The male flowers are green in bud, to flower golden- yellow. In the bud they are triangular together oppressive. The three sepals are fused together into a flat, pointed tricuspid cup. The three petals are valvat. There are either six stamens with short filaments incurved in the bud and upright flowering; or there are three stamens with long filaments that are much incurved and extending horizontally to blossom. The anthers are baxifix, slightly bifid at the tip and base, and open latrors itself. The stamp rudiment is small or absent. The pollen is ellipsoidal and slightly asymmetrical. The germ is opening a distal sulcus. The longest axis measures 25 to 32 microns.

The female flowers are at bloom yellowish. The three sepals are fused together into a tricuspid cup. The three petals are imbricat, twice as long or more as the sepals. The staminodes may be missing; or there are three small; or they are fused into a hexalobal ring which is partly connected with the crown. The gynoecium is ovoid, drefächrig with one ovule, with three stigmas, which are short and bent back. The ovules put on the side, are flattened and laterally campylotrop.

Fruit and seeds

The fruits are relatively large and round to oblong. They are yellow and red to maturity. They carry basal scar remains. The exocarp is smooth, toward the mesocarp fleshy with few anastomosing, flat fibers to the membranous endocarp. The seed is not connected to the endocarp. The basal hilum is inconspicuous. The Raphe branches are large and adaxial rise up from the base, anastomose little, bend laterally from abaxial and rise again. The endosperm is homogeneous or slightly to distinctly furrowed ( ruminat ).

Dissemination and locations

The two species occur in southern Mexico, Central America and northwestern South America. They are quite common in humid forests at sea level and low altitudes, but also rising up to 1200 m above sea level.

System

The genus Synechanthus is placed in the subfamily Arecoideae, Tribe Chamaedoreeae within the family Arecaceae. The genus is monophyletic. The phylogenetic relationships of Synechanthus within the tribe are not released.

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

• Synechanthus fibrosus
• Synechanthus warscewiczianus

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. 375-377.