Australian Tropical Rainforest Plants - Online edition

Syzygium trachyphloium (C.T.White) B.Hyland


Tree
Click/tap on images to enlarge
Leaves and Flowers. © CSIRO
Flowers. © CSIRO
Fruit, many views and cross section. © W. T. Cooper
Scale bar 10mm. © CSIRO
Cotyledon stage, hypogeal germination. © CSIRO
10th leaf stage. © CSIRO
Family

Hyland, B.P.M. (1983) Australian Journal of Botany Supplementary Series 9: 128.

Common name

Rough Barked Satinash; Satinash, Rough Barked; Watergum

Stem

Bark pale brown.

Leaves

Leafy twigs generally 4-angled or shortly 4-winged, pairs of wings running down from each petiole but amalgamating and forming a pocket or hump above the next pair of leaves. Leaf blades about 3.7-9.6 x 1.8-4.5 cm, much paler on the underside. Midrib depressed and petiole grooved on the upper surface. Oil dots numerous, small, but visible to the naked eye.

Flowers

Inflorescence frequently about 3-7 flowered, bracts deciduous, absent at anthesis. Calyx tube (hypanthium) + pedicel about 2-4 mm long, calyx tube (hypanthium) about 2.5-4 mm diam., calyx lobes rounded, concave, dimorphic, inner lobes larger, about 2-2.5 mm long. Petals +/- orbicular, 2.5-4 mm diam., oil dots visible, about 40-50 per petal. Outer staminal filaments about 4-5 mm long, anthers about 0.4-0.5 x 0.3-0.5 mm, gland comparatively large, terminal, near the back of the anther. Ovules about 13-18 per locule, placentas central, ovules radiating, ascending. Style about 4-6.5 mm long, approximating the stamens.

Fruit

Fruits globular, excavated at the apex, attaining about 10-14 x 10-11 mm, calyx lobes persistent, inflexed, about 2-3 mm long. Seed solitary, attaining about 5-6 mm diam., testa +/- free from the succulent pericarp and free from or adhering slightly to the surface of the uniformly textured, petiolate, cotyledons. Radicle lateral or basal, cotyledonary stipules present.

Seedlings

Cataphylls about 1-6 pairs. At the tenth leaf stage: leaf blade obovate, apex bluntly acute or shortly acuminate, base attenuate or cuneate, glabrous; oil dots very small, visible only with a lens; stem distinctly 4-winged. Seed germination time 22 to 32 days.

Distribution and Ecology

Endemic to NEQ, restricted to the area between Cooktown and Cardwell. Altitudinal range from 350-1200 m. Grows in well developed upland and mountain rain forest.

Natural History & Notes

This species produces millable logs and the sawn timber is marketed as Rough-barked Satinash, a useful general purpose structural timber. Wood specific gravity 0.54. Hyland (1983).

Synonyms
Eugenia trachyphloia C.T.White, Contrib. Arn. Arb. 4: 80(1933), Type: Lake Barrine, S. F. Kajewski 1351, holo: A?, iso: BRI, NSW.
RFK Code
173
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