Australian Tropical Rainforest Plants - Online edition

Desmodium trichostachyum Benth.


Herb (herbaceous or woody, under 1 m tall)
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Herbarium specimen. © DERM
Family

Bentham, G. (1864) Flora Australiensis 2: 234. Type: N. Australia. Islands of the Gulf of Carpentaria, R. Brown; Arnhems Land, F. Mueller; Port Essington, Armstrong. Queensland. Endeavour river, Banks and Solander; E. coast, A. Cunningham.

Stem

Prostrate to slightly ascending annual herb with glabrous stems.

Leaves

Leaves 1-3-foliolate; stipules ovate to deltoid, 2.5-4 x 1-1.5 mm long, with parallel veins; petiole 3-12 mm long, with a patch of dense hairs at the top part; rachis 1-4 mm long; leaflets orbicular to broadly oblong, truncate or retuse at the apex, glabrous, sometimes with hairs on abaxial surface; 1-foliolate leaflet 8-20 x 9-20 mm; when 3-foliolate terminal leaflet 5-15 x 6-16 mm, lateral leaflets smaller; stipels 0.2-1 mm long

Flowers

Inflorescence terminal and very open, up to 25 cm long, flowers single subtending by an ovate acuminate bract 1-2 mm long, secondary barcats and bracteoles absent; pedicels slender, 2-6 mm long, doubling in length in fruit. Flowers with calyx 1.4-2.1 mm, pubescent with long white hairs at upper half of lobes; tube 0.5-0.7 mm long, upper lobe 0.8-1.4 mm long, incised to about the middle, other lobes shorter or about equal in length, 0.6-1.3 mm long; corolla purplish; standard obovate, obtuse or retuse at apex, 2.5-3.3 x 2-2.5 mm, wings broad oblong with shrt claw, 1.8-2.5 x 0.7-1.2 mm, keel petals ca. longer and narrower than wings, 2.2-2.9 x 0.7-1 mm, tapered to base.

Fruit

Pods with thickened upper suture, notched between articles, with 3-5 articles, each 2-2.8 mm long and wide, with transverse reticulated veins. Seed 1.3-1.7 x 0.9-1.5 mm, with a rim aril.

Seedlings

Features not available.

Distribution and Ecology

Occurs in WA, NT, CYP, NEQ and CEQ. Altitudinal range from near sea level up to 600 m. Grows in moist to waterlogged areas in Eucalypt forest, vine thicket, various types of woodland and in wooded grassland. Also occurs in southern New Guinea.

Synonyms
Meibomia trichostachya (Benth.) Kuntze, Revisio Generum Plantarum 1: 198(1891).
RFK Code
4229
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