Tristaniopsis exiliflora (F.Muell.) Peter G.Wilson & J.T.Waterh.

Wilson, Peter G. & Waterhouse, J.T. (1982) Australian Journal of Botany 30: 434.

Kanuka box; Kanuka; River Gum; Box, Kanuka; Watergum

Often a poorly formed tree. Bark shed in long strips, the edges of which curl to form cylinders.

Leaf blades about 7.5-11 x 1.5-2.2 cm, much paler on the underside. Midrib depressed on the upper surface.

Inflorescence shorter than the leaves, about 30 flowers per inflorescence. Calyx pubescent, lobes small, about 0.5-1 mm long. Petals about 1.5 mm long. Stamens fused into fascicles opposite the petals, stamens 3-4(-6) per fascicle, fascicles shorter than the petals. Ovary apex pubescent. Style about 1.5 mm long.

Fruits small, splitting to the base at maturity, up to 7 mm diam. when fully open, about 2.5-3 mm diam. before opening, calyx persistent at the base. Seeds small, about 1.5-2 x 1.5 mm, wingless. Cotyledons contortuplicate.

Cotyledons wider than long, bilobed, about 2-3 x 4-6 mm, apex broadly emarginate, base cordate or truncate. Oil dots very small, visible only with a lens. At the tenth leaf stage: leaf blade obovate or narrowly obovate, apex acute, base attenuate, glabrous; oil dots numerous, small, visible with a lens or just visible to the naked eye. Seed germination time 7 to 18 days.

Endemic to Queensland, occurs in CYP and NEQ. Altitudinal range from 50-1000 m. Grows as a rheophyte along creeks and watercourses.