Australian Tropical Rainforest Plants - Online edition

Syzygium graveolens (F.M.Bailey) Craven & Biffin


Tree
Click/tap on images to enlarge
Flower. © Barry Jago
Fruit, three views and cross section. © W. T. Cooper
Scale bar 10mm. © CSIRO
10th leaf stage. © CSIRO
Cotyledon stage, hypogeal germination. © CSIRO
10th leaf stage. © CSIRO
Flower, side view. © CSIRO
Flower bud, side view. © CSIRO
Flower, bird's-eye view. © CSIRO
Family

Craven, L.A., Biffin, E. & Ashton, P.S. (2006) Blumea 51(1): 137.

Common name

Watergum; Cassowary Satinash; Cassowary Gum; Red Watergum; Satinash, Cassowary

Stem

An orange layer of dead bark normally present just outside the subrhytidome layer. Prop roots or flying buttresses may be present.

Leaves

Leaf blades rather thick and leathery, about 11.8-22.2 x 4.9-8.3 cm. Oil dots normally visible with a lens, density variable, sometimes difficult to distinguish in thick leaves. Midrib depressed on the upper surface, at least towards the base.

Flowers

Inflorescence bracts normally present at anthesis. Calyx tube (hypanthium) + pedicel about 3-4.5 mm long, calyx tube (hypanthium) about 2-3.5 mm diam., calyx lobes rounded, about 0.5 mm long. Petals variable in size and shape, +/- orbicular, outer petals about 2 mm diam; oil dots difficult to distinguish, fewer than ten per petal, concentrated towards the base. Outer anther filaments about 1-2 mm long, anthers wider than long, about 0.3 x 0.5 mm, gland comparatively large, terminal, near the front of the anther. Placentas confined to the apex of each locule. Ovules pendulous, about 4-6 per locule. Style about 1-1.5 mm long, shorter than the stamens.

Fruit

Fruits depressed globular to broadly turbinate, attaining about 50-60 mm diam., with a distinct calyx rim or tonsure-like scar persisting at the top; calyx lobes deciduous or at least not obvious; pericarp leathery to almost woody in texture. Seed solitary, attaining about 30-40 mm diam., cotyledons fused, +/- ruminate, or at least texturally different towards the centre because of the haustorium-like intrusion from the apex of the fruit. Intercotyledonary inclusion unbranched but swollen or enlarged towards the central part of the cotyledons.

Seedlings

Cataphylls about 4-6 pairs, opposite or subopposite before the first true leaves and also between leaves at later stages. At the tenth leaf stage: seedling completely glabrous, leaf blade lanceolate, apex acute or apiculate, base cuneate, a double intramarginal vein present; oil dots small and numerous, visible only with a lens. Seed germination time 92 to 153 days.

Distribution and Ecology

Endemic to NEQ, restricted to the area between Cape Tribulation and Tully. Altitudinal range from sea level to 500 m. Grows in well developed lowland rain forest.

Natural History & Notes

This species produces millable logs and the timber is marketed as Cassowary Satinash, a useful general purpose structural timber. Wood specific gravity 0.64-0.68. Hyland (1983).

Synonyms
Acmena graveolens (Bailey) L.S.Sm., Proceedings of the Royal Society of Queensland 67: 34(1956). Cryptocarya graveolens F.M.Bailey, Queensland Department of Agriculture and Stock. Botany Bulletin 2: 16(1891), Type: Tringilburra Creek, Bellenden-Ker Expedition, 1889; Johnstone River, Dr. T.L. Bancroft . Acmena macrocarpa C.T.White, Proceedings of the Royal Society of Queensland 53: 217(1942), Type: Cook District. Between Josephine and Russell Creeks, H. Flecker (type: North Queensland Nat. Club No. 4986), small tree 40 ft., flowers white.
RFK Code
77
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