Sida viscosa Linnaeus, Syst. Nat. ed. 10, 2: 1145. 1759; Bastardia guayaquilensis Turczaninow; B. parvifolia Kunth; S. bastardia de Candolle; S. foetida Cavanilles

Plants 0.5–1.5 m. Stems often malodorous, sometimes also with simple hairs 2 mm. Leaf blades 4–8 cm (often smaller), apex acute to acuminate. Inflorescences usually leafy panicles. Pedicels slender. Flowers: calyx 4–5 mm, viscid; corolla usually 6+ mm, petals 4–5 mm. Schizocarps 5–6 mm diam.; mericarps muticous. Seeds 2 mm. 2n = 28.

Flowering year-round. Shrublands, thickets, disturbed vegetation, pastures, roadsides; 0–500 m; Tex.; e Mexico; West Indies; Central America; South America (Colombia, Ecuador, Peru, Venezuela).

Bastardia viscosa is known only from the lower Rio Grande valley.