Iguanura

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Iguanura
Iguanura spectabilis

Iguanura spectabilis

Systematics
Commelinids
Order : Palm- like arecales
Family : Palm family (Arecaceae)
Subfamily : Arecoideae
Tribe : Areceae
Genre : Iguanura
Scientific name
Iguanura
flower

Iguanura is a genus of palm that is native to Southeast Asia. The representatives are small, pinnate-leaved palms in the undergrowth of the rainforests.

features

The representatives are small, single or multi-stemmed palms with or without an upright trunk. They are unarmed and single sexed ( monoecious ). The trunk is rarely higher than 4 m, the internodes are short to long, the leaf scars inconspicuous. Sometimes stilt roots are formed.

The chromosome number is 2n = 32.

leaves

The leaves are undivided and pinnately ribbed, the end of the leaf can be notched; or the leaves are pinnate regularly or irregularly. The leaves dry up on the trunk or they fall off with a smooth scar. The leaf sheaths are split opposite the petiole. They usually do not form a crown shaft. The petiole may be missing. Growing leaf blades have a reddish tinge. The individual leaflets are folded one or more times.

Inflorescences

The individual inflorescence appears between the leaves, in the types with a corolla below the leaves. It is protandric and spike-shaped or branched one or two times. The inflorescence appears long before flowering, is initially upright, then later arching to pendulous. The inflorescence stalk is very short to very long. The cover sheet is two-keeled, Roehrig, short and mostly enclosed in the leaf sheath. The bract on the inflorescence stalk sits slightly above the cover sheet and is usually much larger than it. The inflorescence axis is significantly shorter than the inflorescence stalk and usually has fewer than 20 side branches. These are bald or densely hairy. The flowers stand in triads that are screwed on the axis and are mostly sunk into pits. There is a lower bract that forms the lower lip of the pit, sometimes an upper lip.

blossoms

The male flowers are sessile, spherical and symmetrical as a bud. After flowering, the calyx usually remains when it falls off. The three sepals are not fused, overlapping, membranous and often keeled. The edge is often lashed. The three petals are valvate, twice as long as the calyx and slightly dome-shaped. The six stamens have long, slender stamens. The anthers are latrors . The pollen grains are ellipsoidal, asymmetrical, sometimes pear-shaped or diamond-shaped. The germ opening is a distal sulcus. The longest pollen axis measures 27 to 45 micrometers.

The female flowers are roughly spherical, slightly larger than the male. The three sepals are not fused, widely overlapping and rounded. The three petals are not fused, longer than the calyx and broadly overlapping. The tips are small and triangular. There are six small staminodes . The pistil is single-fan with an ovule , mostly slightly asymmetrical and ovoid. The three scars are large, fleshy, and bent back. The ovule is semi-anatropic.

fruit

The fruits are egg-shaped, ellipsoidal, bilobed or narrowly spindle-shaped, straight or curved. They are smooth when fresh, smooth or furrowed when dry. Their color can be green, white, brownish or pink to bright red. The remains of the stigma are basal, the flower shell remains on the fruit. The exocarp is smooth and shiny, the mesocarp fleshy, the endocarp clearly developed, woody and smooth to furrowed.

Distribution and locations

The genus occurs on Sumatra , the Malay Peninsula including the southern tip of Thailand, and Borneo . All representatives grow in the understory of primary tropical rainforests, often they grow in larger groups. They occur from sea level to about 1200 m above sea level. Iguanura wallichiana is very common in Malaysia. Many other species are confined to a small area, especially those found on Borneo.

Iguanura wallichiana var. Major
Iguanura melinauensis

Systematics

The genus Oncosperma is within the family Arecaceae in the subfamily Arecoideae , tribe Areceae . Within this tribe it is not assigned to any subtribe, its systematic position is still unclear. The monophyly of the genus has not yet been investigated.

Govaerts and Dransfield accept the following species in the World Checklist of Palms :

The genus was first described by Blume in 1838 , the type species is Iguanura leucocarpa . The generic name Iguanura means lizard tail and refers to the scaly inflorescence axes.

use

The species are not subject to any specific use. The leaves are rarely used to cover shelters. According to one study, roots and fruits should have a contraceptive effect.

literature

  • 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. 638-641.

Individual evidence

  1. ↑ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah Rafaël Govaerts (Ed.): Iguanura. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved August 7, 2018.

Web links

Commons : Iguanura  - collection of images, videos and audio files