1. Achyranthes aspera Linnaeus, Sp. Pl. 1: 204. 1753.
Centrostachys aspera (Linnaeus) Standley
Plants perennial or annual. Stems 0.4-2 m, pilose or puberulent. Leaf blades elliptic, ovate, or broadly ovate to orbiculate, obovate-orbiculate, or broadly rhombate, 1-20 × 2-6 cm, adpressed-pubescent abaxially and adaxially. Inflorescences to 30 cm; bracts mem-branous; bracteoles long-aristate, spinose; wings attached at sides and base. Flowers: tepals 4 or 5, length 3-7 mm; pseudostaminodes with margins fimbriate at apex, often with dorsal scale. Utricles ± cylindric, 2-4 mm, apex truncate or depressed.
Varieties 6 (2 in the flora): se United States, Mexico, West Indies, Central America, South America, Eurasia, Africa.
Achyranthes aspera is a variable, pantropical species divided into six varieties (C. C. Townsend 1974), two of which occur in the flora. The variety with a long perianth and acuminate leaves has long been called var. aspera; the variety with a short perianth and blunt leaves, var. indica. However, A. Cavaco (1962) showed that the type of var. indica must be the type of the species A. aspera, thus var. indica is a homotypic synonym of var. aspera. Townsend made the combination A. aspera var. pubescens for plants previously called var. aspera.