Australian Tropical Rainforest Plants - Online edition

Phylacium bracteosum Benn.


Slender Vine
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Habit, leaves, immature and mature fruits. © B. Gray
Leaves and fruits. © CSIRO
Scale bar 10mm. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO
10th leaf stage. © CSIRO
Family

Bennett, J.J. (1844) Plantae Javanicae Rariores : 159. Type: (Plantae Javanicae Rariores Plate 4?) ?.

Stem

A slender vine not exceeding a stem diameter of 2 cm.

Leaves

Middle leaflet blade about 5.5-6.4 x 3.3-4 cm, stalk about 0.5-1 cm long. Lateral leaflet blades about 4.3-5.2 x 2.5-3.2 cm, stalks about 0.3-0.4 cm long. Compound leaf petiole about 5.7-6.5 cm long. Stipules hairy, narrowly triangular, about 3-4 mm long. Stipels hairy, filiform, about 2 mm long. Lateral veins about 6-8 on each side of the midrib and forming loops inside the blade margin. Lower surface of the leaflet blades densely clothed in prostrate white hairs.

Flowers

Flowers borne in condensed secund racemes, the whole inflorescence enclosed in a large green bract. Flower stalks about 3 mm long, but the flowers are technically sessile because there are two linear hairy bracts each about 1 mm long attached to the base of the calyx tube. Calyx tube about 2 mm long, lobes about 1 mm long, one larger than the other. Petals: standard about 9 mm long; wings about 9 mm long; keel about 7 mm long. Stamens 10, the filaments of nine stamens fused to form a tube open on one side. Free part of the filaments alternately long and short. One stamen free. Disk fleshy, surrounding the base of the style. Ovary shortly stalked, about 0.7-0.8 mm long, laterally compressed. Style about 3 mm long. Ovary and lower style clothed in pale prostrate hairs. Stigma terminal, globular. Ovules one.

Fruit

Fruits about 10-11 mm long, asymmetrical, outer surface reticulately veined and clothed in short pale hairs. Style remnants persistent at the apex, calyx remnants persistent at the base. Fruits enclosed in a leaf-like bract open on one side. Bract about 30 x 17 mm, reticulately veined. Seed reniform, about 5 mm long. Hilum almost orbicular, less than 1 mm diam. Radicle curved around the margin of the cotyledons. Radicle about 2 mm long, much shorter and narrower than the cotyledons.

Seedlings

Cotyledons asymmetrical, +/- falcate and elliptic to reniform, about 10-11 x 7-8 mm, base obtuse and oblique. Petioles about 1 mm long. First leaf unifoliolate, +/- orbicular, about 15-16 mm diam., apex mucronate, base shallowly cordate. Petiole (leaf stalk) hairy, about 10 mm long. Third leaf trifoliolate. At the tenth leaf stage: leaflet blades elliptic, apex obtuse to retuse and mucronate, base obtuse or truncate. Lower surface clothed in pale prostrate hairs, upper surface glabrous. Stipules hairy, narrowly triangular to linear-lanceolate, about 3-5 mm long. Stipels present. Stems twining, clothed in pale backward-pointing hairs. Crushed roots emit an odour like that of fresh beans (Phaseolus vulgaris). Seed germination time 12 days.

Distribution and Ecology

Occurs in CYP. Altitudinal range from near sea level to 100 m. Grows in rain forest and gallery forest. Also occurs in New Guinea and other parts of Malesia, also in SE Asia.

Natural History & Notes

This species is of no grazing significance. Hacker (1990).

RFK Code
2631
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