Flora Zambesiaca

Taxon Detail

FZ volume:1 part:1 (1960) Annonaceae by N. K. B. Robson

Annonaceae Key

Range:

A family of over 100 genera and over 1,000 species, almost confined to the tropical and subtropical regions of both hemispheres apart from Asimina in eastern N. America.

Description:

Trees, shrubs, or lianes (rarely rhizomatous shrublets), glabrous or with an indumentum of simple, stellate or lepidote hairs; bark usually smooth and entire, pale grey or buff to brown, the branches often reddish to purple-black with lozenge-shaped striations, pubescent or tomentose (rarely glabrous) when young; pith septate, oil cells present. Leaves alternate in two rows, entire, penninerved, membranous to coriaceous, exstipulate. Flowers morphologically terminal (i.e. terminal, supra-axillary, extra-axillary or leaf-opposed) or axillary, solitary or paired to fasciculate or cymose, on the young or old wood, sessile or pedicellate, more rarely pedunculate, actinomorphic, bisexual or more rarely unisexual, often fragrant. Sepals 3 (2), usually valvate in bud, free or ± united. Petals 6 (4) in two equal or ± unequal whorls (more rarely one whorl of 6, 4 or 3), imbricate or valvate (rarely open) in bud, free or ± united at the base, usually alternating with the sepals. Stamens ?, spiral, or 6–12 and whorled (sometimes staminodial) with anthers linear to semi-orbicular, lateral or extrorse (rarely apical); connective usually prolonged beyond the thecae, with the apex truncate, oblique, capitate, convex, conical or acute; filaments usually very short or absent, free, rarely more elongate and united in a cone over the gynoecium (Xylopia). Carpels ?–1 free or united at the base, or completely united to form a 1-locular ovary (Monodora); ovules ?–1: styles free or united, or absent. Fruit apocarpous with ripe carpels baccate (fleshy or lignified) or rarely dehiscent, stipitate or sessile, or syncarpous with either aggregated 1-seeded carpels or 1-locular and ?-seeded, Seeds vertical to horizontal, sometimes arillate, with abundant ruminate endosperm; embryo minute.

Notes:

In addition to the above genera, Cananga odorata (Lam.) Hook. f. & Thorns, from tropical Asia is cultivated in our area.