Families of Flowering Plants of Australia

Xanthophyllaceae

This small, Indomalayan family comprises only one genus, Xanthophyllum, found in Australia in the rainforests of Cape York Peninsula.

Characteristic features of the family Xanthophyllaceae in Australia include:

small trees with alternate, entire leaves that often have a few crater-like glands (extra-floral nectaries) near their bases
flowers zygomorphic, in terminal or axillary cymes, the front petal keel-shaped and enclosing 8 free stamens
ovary superior, forming a globular, indehiscent fruit

Description

Evergreen or semi-deciduous trees. Extra-floral nectaries absent, or rarely nectary-like glands present at the base of the petioles. Internal secretions not obvious. Plants glabrous or with simple, non-glandular, unicellular hairs. Leaves alternate and spiral, petiolate or subsessile. Stipules absent. Lamina simple, symmetric, lanceolate or ovate; base cuneate; margins entire, ±flat; one-veined, or the venation pinnate, with the midrib conspicuous, and the tertiary venation reticulate; surfaces not punctate; leathery. All the flowers bisexual. Inflorescences terminal or axillary, consisting of dichasial cymes. Bracts and bracteoles absent. Pollination by insects. Flowers fragrant, stalked. Floral disc present. Perianth of 2 dissimilar whorls, imbricate in bud. Calyx regular; segments free, of 4–5 sepals, herbaceous or papery. Corolla irregular; segments free, of 4–5 petals, alternating with the sepals; corolla 1-lipped or pea-flower-like, white, cream or yellow, without contrasting markings, membranous; claws present; lobes ±entire. Fertile stamens (7–) 8 (–9), both opposite to and alternating with the sepals, free of the corolla, free of the ovary and style, distinct from each other, all ±equal. Anthers dorsifixed, not versatile, opening inwards by longitudinal slits, 2-celled. Ovary superior, stalked or sessile. Carpel 1; ovary with 1 locule. Style terminal, single and unbranched. Ovules 1–3, stalked; placentation parietal. Fruit dry or somewhat fleshy, dehiscent or indehiscent; an 'indehiscent capsule' (carcerulus); the perianth on the maturing fruit deciduous. Disseminule micro-surface ±smooth, yellow, brown or black, glossy or dull. Seeds 1 per fruit. Aril absent. Cotyledons 2. Embryo round or shapeless.
(Note: this description has been generated from the coded data compiled for the key. Any errors in the key data will be reflected in the descriptions.)

A treatment of the family Xanthophyllaceae has not yet been published in the Flora of Australia. It will appear in Volume 24.

Australian genera of Xanthophyllaceae (as recognised for the Flora of Australia)

Xanthophyllum