Acmadenia tetracarpellata I.Williams

Shrubs 0.5 m tall, spreading 1 m diam., dense, light green in colour, the lower branches becoming buried in sand, single stemmed at base. Branches numerous, stout at base, sub-dichotomous, somewhat spreading, very much interwoven, glabrous with a greyish brown fairly rough bark. Branchlets very numerous, slender, fairly erect, sparsely puberulous, with a few gland-dots. Leaves 3 mm long, 1.5-2.5 mm broad, elliptic or orbicular, obtuse, thick, apex with a blunt immersed gland, margins thick and gland-dotted, midrib with scattered gland-dots, sparsely puberulous on all sides, sub-glaucous, sessile, opposite, spreading, decussate, often widely spaced on the uppermost branchlets. Inflorescence 2-nate, terminal, white, inconspicuous. Bracts leaf-like in opposite pairs, 1.5 mm long, 1.3 mm broad, orbicular, puberulous, thick, sessile, spreading, apex curiously swollen with a submerged gland, midrib gland-dotted. Bracteoles two, 0.7 mm long, 0.5 mm broad, orbicular, thick, ciliolate, sparsely puberulous on both sides with a single gland-dot at the apex. Calyx lobes five, 1.2 mm long, 0.7-0.8 mm broad, oblong, obtuse, minutely ciliolate, minutely puberulous, with one or two small gland-dots on the midrib and at the apex. Petals five, 2 mm long, 0.9 mm broad, lanceolate, obtuse, sessile, spreading, white, very sparsely pubescent on the abaxial surface and on the inner surface towards the base, margins serrulate and revolute. Staminodes five, 0.3-0.5 mm long, apex glandular. Filaments five, glabrous, acicular, becoming 1.2 mm long. Anthers five, before anthesis 0.7 mm long, 0.5 mm broad, yellow tinged with pink, with a minute sessile apical gland. Pollen 40 µ long, 20 µ diam., oblong. Disc green, sub-sinuate, equals or exceeds the ovary, exudes nectar. Stigma 0.2 mm diam., capitellate, globose. Style glabrous, terete, at first deflexed becoming 0.8 mm long. Ovary 4-carpellate, 0.7 mm diam., glabrous. Fruit normally 4-carpellate, 5 mm long, 4 mm diam., reddened, gland-dotted, very sparsely puberulous, with horns 1.5 mm long, puberulous, with an immersed gland at the apex, spreading at 45°, petals and style persisting. Seed 3.2 mm long, 1.5 mm broad, black, shining.