Cardiopteridaceae

This small family comprises a single genus, Cardiopteris (also called Peripterygium), found from India through South-East Asia to north-east Australia. One species occurs in Australia, in rainforest of north Queensland.

Characteristic features of the family Cardiopteridaceae in Australia include:

• climbing herbs with milky sap
  
• leaves large, heart-shaped with palmate venation
  
• flowers small, regular, in axillary cymes; calyx at least partly fused
  
• there are two types of style on each ovary, one elongate and one short and head-like
  
• fruits dry, two-winged, indehiscent

Description

Perennial herbaceous vines climbing by twining stems. Internal secretions of milky sap (latex). Plants glabrous or with simple, non-glandular hairs. Leaves alternate and spiral, cauline, petiolate. Stipules absent. Lamina simple, symmetric, lanceolate or ovate; base rounded or cordate; margins entire, ±flat; venation palmate, with the midrib conspicuous, and the tertiary venation not reticulate; surfaces not punctate; herbaceous. Bisexual flowers and either male or female flowers occurring on the same plant, or with all the flowers bisexual. Inflorescences axillary, consisting of monochasial cymes. Bracts and bracteoles absent. Flowers stalked. Floral disc absent. Perianth regular, of 2 dissimilar whorls, imbricate in bud. Calyx segments fused, with 5 lobes; calyx bell-shaped, herbaceous. Corolla segments fused, with 5 lobes, alternating with the calyx lobes; corolla funnel-shaped, white, without contrasting markings, membranous; lobes ±entire. Fertile stamens 4 or 5, opposite to the calyx lobes, at least partly fused to the corolla, free of the ovary and style, distinct from each other, all ±equal. Anthers basifixed, not versatile, opening inwards by longitudinal slits; 2-celled. Ovary superior and sessile. Carpels 2, fused; ovary with 1 locule. Style terminal, branching from the base. Ovules 1–2, stalked; placentation apical. Fruit a dry, indehiscent samara; the perianth on the maturing fruit deciduous or dry and persistent. Disseminule macro-surface winged; micro-surface ±smooth, yellow or brown, glossy. Seeds 1 (–2) 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 Cardiopteridaceae has been published in:
Flora of Australia 22: 212-213.

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

Cardiopteris

Cardiopteris moluccana