Surianaceae

This small family is principally Australian, although Suriana maritima is found throughout the tropics along coastlines. The other Australian genera are found in the Central and Western Deserts (Stylobasium) and in rainforests and vine scrubs in Queensland and northern New South Wales (Guilfoylia and Cadellia).

Characteristic features of the family Surianaceae in Australia include:

• trees or shrubs, often greyish, with alternate, simple leaves
  
• flowers small, regular, with 5 sepals more or less fused into a cup, 5 free petals (or the petals absent) and 10 stamens
  
• ovary superior, of 1 carpel (Stylobasium and Guilfoylia) or 5 free carpels (Cadellia), each with 2 funicled ovules and a style that arises from the base of the ovary
  
• fruits are dark-coloured drupes, berries or nuts

Description

Evergreen trees or shrubs. Stem nodes conspicuously swollen. Internal secretions not obvious. Plants glabrous, or with simple, non-glandular, unicellular or uniseriate hairs. Leaves alternate and spiral, petiolate. Stipules absent, or present and distinct and free from the petiole, scale-like or membranous, falling off early. Lamina simple, symmetric, filiform, acicular, subulate, linear, lanceolate, ovate, elliptic or oblong; base cuneate or attenuate; margins entire, ±flat; venation pinnate, or parallel, with the midrib conspicuous, and the tertiary venation not reticulate; surfaces not punctate; herbaceous. All the flowers bisexual. Inflorescences terminal or axillary, consisting of panicles, cymes or solitary flowers. Bracts present. Pollination by insects or wind. Flowers stalked. Floral disc present; nectaries absent. Perianth regular, of 2 dissimilar whorls, imbricate in bud. Calyx segments free or fused, with 5 sepals or lobes; calyx cup-shaped or bell-shaped, herbaceous. Corolla segments free, with 5 petals, alternating with the sepals or calyx lobes, white, cream, yellow, green, brown or purple, without contrasting markings, membranous; lobes ±entire. Fertile stamens 5 or 10, opposite to, or both opposite to and alternating with, or not clearly correlated with the sepals or calyx lobes, free of the corolla, free of the ovary and style, distinct from each other, all ±equal. Staminodes present or absent. Anthers dorsifixed or basifixed, versatile or not versatile, opening sideways by longitudinal slits, 2-celled. Ovary superior and sessile. Carpels 1 or 5, free. Style gynobasic, single and unbranched, or feathery, or disc shaped. Ovules 2–5 per carpel, stalked; placentation basal. Fruit a dry indehiscent nut, or a fleshy berry, or a drupe; the perianth on the maturing fruit deciduous, dry and persistent, or growing larger. Disseminule macro-surface featureless or with straight hairs; micro-surface ±smooth, brown, grey or black, glossy or dull. Seed 1 per fruit. Aril absent. Cotyledons 2. Embryo curved or sharply bent.
(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 Surianaceae has not yet been published in the Flora of Australia. It will appear in Volume 10.

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

Cadellia
Guilfoylia
Stylobasium
Suriana