Australian Tropical Rainforest Plants - Online edition

Xanthostemon umbrosus (A.Cunn. ex Lindl.) Peter G.Wilson & J.T.Waterh.

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Leaves and Flowers. © CSIRO
Leaves, Flowers and Fruit. © A. Ford & F. Goulter
Scale bar 10mm. © CSIRO
10th leaf stage. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO

Wilson, Peter G. & Waterhouse, J.T. (1982) Australian Journal of Botany 30: 444.


Fine, pale brown brittle stripes in the blaze.


Oil dots visible with a lens if not visible to the naked eye. About 1-6 oil dots per reticulation. Leaf blades about 5-8 x 2-4.5 cm. Midrib projecting beyond the end of the leaf blade as a small point. Terminal buds and young shoots densely clothed in short, erect, brown or ginger hairs.


Inflorescence appears terminal but is not strictly so. Calyx tube (hypanthium) and lobes clothed in short ferruginous hairs. Petals glabrous, about 5-10 x 5-10 mm, abruptly narrowed into a claw, about 1.5 mm wide. Staminal filaments about 12-14 mm long, anthers with a large oil gland at the tip of the connective. Style about as long as the stamens.


Fruits +/- globular, about 10-12 mm diam., calyx lobes persistent at the base. Seeds about 5 x 3.5 mm.


Cotyledons +/- reniform, about 4 x 7 mm, oil dots visible with a lens. At the tenth leaf stage: leaf blade elliptic, both upper and lower surfaces clothed in pale, +/- tortuous hairs; oil dots visible with a lens; stem clothed in pale, erect, hairs. Seed germination time 13 to 35 days.

Distribution and Ecology

Endemic to Australia, occurs in WA, NT, CYP and NEQ. Altitudinal range from sea level to 300 m. Grows in dry rain forest, monsoon forest and beach forest but is probably most characteristic of scrubby vegetation in crevices and gorges in sandstone.

Tristania umbrosa A.Cunn. ex Lindl., Bot. Reg. : 1839(1836), Type: Western Australia, Shores of York Sound, A. Cunningham 16 sept. 1820; holo: CGE; iso: BM, K. Metrosideros tetrapetala F.Muell., Fragm. 7: 41(1869), Type: Qld, Cave Creek, Gilbert River, Daintree; lecto: MEL63313. Fide Wilson (1990). Nania tetrapetala (F.Muell.) Kuntze, Revisio Generum Plantarum 1: 242(1891).
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