Acalypha lanceolata Willd.

Euphorbiaceae

Willdenow, C.L. von (1806) Species Plantarum Edn. 4 4: 524. Type: J.Burman, Thes. Zeylan.: 205 (1737) t.93,fig.2.

Erect sparsely branched annual herb up to 60 cm tall with cylindrical green stems.

Leaf blades 35-80 x 16-56 mm, petioles 20-80 mm long. Leaf surfaces clothed in hairs. Oil dots readily visible with a lens. Stipules 0.5-4 x ca. 0.1 mm, broad at the base but narrowed to an acuminate tip. Lateral veins 4-5 on each side of the midrib. Margins toothed with 16-22 teeth on each side.

Inflorescence up to 25 mm long, racemes consists of male flowers in the upper part and female flowers in the lower part. Male flowers: Flowers ca. 0.1 mm diam. Tepals about 0.3 mm long. Stamens ca. 0.4 mm long. Female flowers: Flowers ca. 1 mm diam. surrounded by deeply lobed bracts ca. 1.5 mm long. Tepals ca. 0.4 mm long. Ovary densely clothed in hairs. Styles lacinate, ca. 1 mm long. Ovules one per locule.

Fruits 3-lobed, depressed-globose, 1.5-2 x 2-3 mm, clothed in long translucent hairs and subtended by a large leaf-like bract.

Seeds globose to ovoid, 1.1-1.8 x 0.8-1.1 mm, faintly patterned and light brown. Embryo about 1 mm long, radicle shorter than the cotyledons or as long as the cotyledons.

Occurs in WA, NT, CYP, NEQ and CEQ. Altitudinal range from near sea level to 760 m. Grows in vine forest but also in various types of woodland and grassland. Widespread in the palaeotropics including the Philippines and New Guinea.

Becomes a weed of cultivation (Forster 1994).