Sida crispa Linnaeus, Sp. Pl. 2: 685. 1753; Abutilon crispum (Linnaeus) Medikus; A. sessifolium C. Presl; Bogenhardia crispa (Linnaeus) Kearney; Gayoides crispa (Linnaeus) Small; Sida amplexicaulis Lamarck; S. imberbis de Candolle; S. retrofracta de Candolle; S. sessilis Vellozo

Plants sometimes sprawling, 1–6 dm. Leaves petiolate to 52 mm, sessile distally; blade ovate to sometimes elongate-triangular, 1–8 cm, apex acuminate. Flowers: calyx rotate in flower to reflexed in fruit, 3–7 mm; petals 6–11 mm. Schizocarps on jointed pedicel near fruit; mericarps 10–12, to 10 mm, walls thin, papery. 2n = 14.

Flowering Mar–Jan. Forests, grasslands, roadsides, weedy or disturbed sites; 0–2000 m; Ariz., Calif., Fla., N.Mex., Tex.; Mexico; West Indies; Central America; South America; introduced in Asia, Australia.

Given the weedy nature of Herissantia crispa, it would not be surprising to encounter it in other warm regions adjacent to the currently documented distribution.