Australian Tropical Rainforest Plants - Online edition

Cryptocarya glaucescens R.Br.

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Leaves. CC-BY: APII, ANBG.
Inflorescence. CC-BY: APII, ANBG.
Flowers. CC-BY: APII, ANBG.

Brown, R. (1810), Prodromus Florae Novae Hollandiae: 402. Type: R. Brown s.n., Hawkesbury River (BM, lectotype, fide Frodin (1976); MEL 623249, isolectotype); R. Brown. Port Jackson & Hawkesbury River (BM, K, MEL, G-DC?, lectoparatypes).

Common name

Jackwood; Silver Sycamore


Tree to 30 metres; bark dark-brown, more or less scaly; buds and young stems with fawn to brown hairs; stems glabrous; young stems yellowish; stipules absent.


Simple, alternate; lamina oblong elliptic to lanceolate, 60-130mm by 25-40mm; adaxial surface glabrous and glossy; abaxial surface glaucous and dull, glabrous or with sparse hairs; apex acuminate to a blunt tip or evenly tapered to an acute tip; base cuneate or rounded; margin entire; midrib broad and yellowish; pinnately veined with 8-12 main laterals each side of midrib, distinct both surfaces; reticulum areolate; oil dots numerous, minute; petiole 8-12mm, yellowish; domatia absent.


Inflorescences axillary panicles, not longer than leaves; flowers bisexual, actinomorphic, cream to green; perianth of 2 whorls each of 3 pubescent tepals borne on a tubular hypanthium 1-1.5mm long; stamens 9, outer stamens pubescent adaxially; inner stamens glabrous; staminodes 3; ovary superior, glabrous.


Completely enclosed within a fleshy receptacle to form a ‘false-fruit’ in which the ovary appears inferior; remnants of the perianth (tepals) are visible on the top of the false-fruit; false-fruit depressed-globose, 11-15mm long by 12-18mm wide, ribbed or lobed, glossy black; seed 1, 9-13mm long.


Seed germination time 28 days. First pair of leaves lanceolate, about 50-70 x 24-28 mm, glaucous on the underside. At the tenth leaf stage: leaf blade elliptic to lanceolate, apex acuminate; upper surface of new leaves hairy only along midrib; oil dots small, visible. Petiole hairy.

Distribution and Ecology

Occurs in CEQ, possibly as far north as Mt Elliot, and southwards to south eastern New South Wales. Altitudinal range from sea level to 1000 m. Grows in rain forest usually on poorer soils derived from sedimentary and acid volcanic rocks.


Cryptocarya hypoglauca var. attenuata Meisn., Prodromus Systematis Naturalis Regni Vegetabilis 15(1): 508 (1864), Type: Hastings River, N.S.W., F.Mueller s.n. (probably H.Beckler); holo: G-DC.  Cryptocarya meissneri F.Muell., Fragmenta Phytographiae Australiae 5(38): 170 (1866).  Cryptocarya glaucescens var. nitida Benth., Flora Australiensis 5: 297 (1870).  Cryptocarya moretoniana Meisn., Prodromus Systematis Naturalis Regni Vegetabilis 15(1): 74 (1864), Type: Moreton Bay, A. Cunningham 48/1829.

RFK Code


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