Sida acuta Burm.f.
Burman, N.L. (1768) Flora Indica : 147. Type: Habitat in India.
Sida; Sida, Spinyhead; Southern Sida; Spinyhead Sida; Sida, Southern
Usually flowers and fruits as a shrub about 1-1.5 m tall, occasionally flowers when smaller.
Leaf blades about 4 x 0.8 cm, margin coarsely serrate, each tooth ending in a single hair. Stipules in each pair differing from one another, one stipule linear to lanceolate and 3-6 veined about 8 x 0.5 mm; the other stipule linear to filiform, shorter and 1-4 veined. Stellate hairs present on the twigs and petioles. Stem and twig bark strong and fibrous when stripped.
Calyx 10-ribbed, at least towards the base, about 6-8 mm long, outer surface clothed in stellate hairs. Petals about 7-8 mm long, attached to the base of the staminal column and falling off with it. Stamens about 30, arranged in five bundles of 6. Ovary about 5-10 locular. Styles and/or stigmas protrude from among the mass of anthers.
Cotyledons almost orbicular, about 6 mm diam., apex shortly apiculate, petioles about 3 mm long. First pair of leaves +/- obovate, margins toothed, lower surface clothed in stellate hairs, upper surface clothed in simple hairs. At the tenth leaf stage: leaf blade ovate, apex acuminate, base cuneate. Stipules hairy, filiform, about 9-11 mm long, one stipule in each pair wider than the other. Stem bark very fibrous when stripped. Seed germination time 21 to 77 days.
This species may have medicinal properties.