home browse overview
 
 

Aristolochiaceae


This is a moderate-sized family from the tropics and subtropics of all continents. Several species of Aristolochia, the only genus in Australia, are found at rain forest margins in northern and eastern Australia.

Characteristic features of the family Aristolochiaceae in Australia include:

  • twining herbs or woody lianes
  • leaves alternate, usually with 3-5 palmate veins from a cordate base
  • flowers peculiar, curved-tubular, zygomorphic, with a 1-whorled, fused perianth-tube, usually dark-coloured and with a foetid odour to attract flies for pollination
  • ovary 6-chambered, more or less inferior, developing into a many-seeded capsule usually fragmenting from the base

Description

Evergreen woody or herbaceous vines climbing by twining or scrambling stems. Internal secretions not obvious. Plants glabrous or with simple, non-glandular hairs. Leaves alternate and spiral, petiolate. Stipules absent. Lamina simple, symmetric, lanceolate, ovate or oblong; base cordate; margins entire, ±flat; venation pinnate, or palmate, with the midrib conspicuous, and the tertiary venation reticulate; surfaces pellucid-punctate or not punctate; herbaceous; aromatic. Plants with all the flowers bisexual. Inflorescences axillary or leaf opposed, consisting of spikes, racemes, dichasial cymes or solitary flowers. Bracts and bracteoles absent. Pollination by insects. Flowers odourless or malodorous; sessile or stalked. Floral disc absent; nectaries present on the perianth. Perianth irregular, of 1 whorl only, with 03, fused, petaloid segments, imbricate in bud, cup-shaped, funnel-shaped or curved-tubular, yellow, magenta, purple, violet or green, without contrasting markings, or streaked, spotted, etc, membranous; lobes ±entire. Fertile stamens 6 or numerous, free of the perianth, at least partly fused with the ovary or style, distinct from each other, all ±equal. Anthers dorsifixed, not versatile, opening outwards by longitudinal slits; 2-celled. Ovary part-inferior or inferior. Carpels 6, fused; ovary with 46 locules. Style terminal, single and unbranched, or single and branched above. Ovules numerous per locule, stalked or sessile; placentation parietal or axile. Fruit dry or somewhat fleshy, a capsule with irregular or septicidal dehiscence. Disseminule macro-surface winged; micro-surface ±smooth, brown. Seeds numerous per fruit. Aril absent. Cotyledons 0 or 2. Embryo straight, 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 Aristolochiaceae has not yet been published in the Flora of Australia. It will appear in Volume 2.

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

Aristolochia


Aristolochia deltantha (flower)
Photo: G.Sankowski Zodiac Publications 


Aristolochia deltantha (fruit)
Photo: H.Nicholson H. & N. Nicholson 


Aristolochia praevenosa (flowering branch)
Photo: G.Leiper G.Leiper 


Aristolochia sp. (flowers)
Photo: G.Sankowski Zodiac Publications