Dransfieldia micrantha

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Dransfieldia micrantha
Systematics
Monocots
Commelinids
Order : Palm- like arecales
Family : Palm family (Arecaceae)
Genre : Dransfieldia
Type : Dransfieldia micrantha
Scientific name of the  genus
Dransfieldia
WJBaker & Zona
Scientific name of the  species
Dransfieldia micrantha
( Becc. ) WJBaker & Zona

Dransfieldia micrantha is only Guinea occurring plant species from the family of the palm family (Arecaceae). It is the only species in the genus Dransfieldia .

features

Dransfieldia is a multi-stemmed, unreinforced palm, more rarely it only forms one trunk. The trunk reaches a height of up to 10 m with a diameter of 2 to 5 cm. The trunk surface is smooth, often reddish when young, later brown. The internodes are 4.0 to 19.5 cm long. The crown consists of 4 to 7 leaves . Young leaves are reddish at first and then turn green. With a leaf stalk , they are 1 to 2 m long. The leaf sheath is 30 to 45 cm long. The petiole is 10 to 20 cm long. There are 12 to 27 leaflets on each side of the rhachis . The leaflets in the middle of the leaf are 52 to 76 cm long and 2 to 5 cm wide, those at the leaf tip are 18 to 36 cm long.

The inflorescence is 34 to 60 cm long, of which the inflorescence stalk takes 12 to 26 cm. All axes of the inflorescence are red to purple at flowering time. The cover sheet is 11.5 to 27 cm long and 1.4 to 2 cm wide and brown when it blooms. There are two to three bracts on the peduncle, the first 20 to 24 cm long and 1.7 to 3.5 cm wide, the remaining 0.5 to 25 cm long and 5 to 12 mm wide. The inflorescence axis is 9 to 17 cm long, from it go from 11 to 14 side axes that are up to 35 cm long. Each of these again carries up to 7 side axes that are 8.5 to 29 cm long. On them, the flowers stand in threes in the axils of small, up to 1 mm long bracts. There are 15 to 28 of these triads on a 5 cm lateral axis.

The male flowers are 4.5 to 5.5 × 2.2 to 3.4 mm in size shortly before opening, and purple. The sepals are fleshy. The petals are fused together in the lowest part. There are 15 to 19 white stamens , their stamens are 1.5 to 3.1 mm long, the anthers 1.0 to 1.3 mm. The ovary rudiment is less than 0.5 mm in size.

The female flowers are 3.8 to 4.3 × 2.2 to 3.4 mm in size shortly before opening and are also purple. Most of the three staminodes are 0.3 to 0.5 mm long. The gynoeceum , including the scars, is around 3.0 × 1.6 mm in size and ovoid. It is pseudomonomer, has only one fruit compartment with an ovule , but three scars.

The fruit is ellipsoidal and 15.0 to 15.9 × 7.6 × 9.5 mm in size. The exocarp is black, thin, smooth, and black to maturity. The epicarp and the fibrous mesocarp are 0.7 mm thick, the endocarp 0.3 mm. The latter is brown. The seeds are 8.9 to 11.0 × 6.1 to 7.0 mm in size. The scar is basal, the raphe on the side. The endosperm is deeply furrowed (ruminate), the embryo is basal.

distribution

The species occurs only in the west of the Indonesian part of New Guinea. Locations are known from the island of Waigeo , Kapala Burung , the lower slopes of the Wondiwoibergen and from the vicinity of Etna Bay . It grows in the undergrowth of lowland rainforests and the forests of the hillsides and ridges at 10 to 180 m above sea level.

Systematics

The species was first described in 1872 by Odoardo Beccari as Ptychosperma micranthum . The classification in the genus Ptychosperma was challenged in 1883 by Joseph Dalton Hooker , who placed it in the genus Rhopaloblasts . Harold Moore placed them in the genus Heterospathe . In general, however , the basionym was considered to be the accepted name. In 2006 the species was transferred to its own genus Dransfieldia due to its morphological and molecular genetic characteristics . The genus name honors the palm researcher John Dransfield (born 1945) from the Royal Botanic Gardens, Kew .

Molecular genetic analyzes indicate the purely New Caledonian subtribe Clinospermatinae as a sister group of Dransfieldia , but with little statistical support. Therefore, the species was assigned to the Areceae tribe , but no subtribe within it.

use

The logs are processed into harpoons . The leaves are used for roofing. The species is grown as an ornamental plant in the USA and Australia, but not widely used in trade.

literature

  • William J. Baker, Scott Zona, Charlie D. Hautubun, Carl E. Lewis, Rudi A. Maturbong, Maria V. Norup: Dransfieldia (Arecaceae) - A New Palm Genus from Western New Guinea . Systematic Botany, Volume 31, 2006, pp. 61-69.

Individual evidence

  1. Lotte Burkhardt: Directory of eponymous plant names . Extended Edition. Botanic Garden and Botanical Museum Berlin, Free University Berlin Berlin 2018. [1]

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