Spigelia anthelmia
Sp. Pl. 1: 149. 1753.
Herbs annual, 15–40 cm; rhizome absent. Stems 1, sparsely to profusely branched. Cauline leaves: proximals 0 or 1 pair per stem, sessile or petiolate, blade narrowly lanceolate to linear, 1.5–6.3 × 0.4–1.5 cm, base narrowly cuneate; distals pseudowhorled, 2 unequal pairs. Cymes 22–45-flowered. Flowers: calyx lobes lanceolate-subulate, 2–3(–4) mm; corolla white, each lobe with 2 vertical purple stripes, funnelform, 6–9 mm, lobes spreading at anthesis. Capsules 4–5 × 4–7 mm, muricate distally. Seeds 2 mm. 2n = 32.
Phenology: Flowering year-round.
Habitat: Disturbed and cultivated soils, roadsides.
Elevation: 0–200 m.
Distribution
Fla., s Mexico, West Indies (Cayman Islands, Cuba, Dominican Republic, Haiti, Jamaica, Puerto Rico, Virgin Islands), Central America (Belize, Costa Rica, El Salvador, Honduras, Nicaragua, Panama), n South America (French Guiana, Guyana, Suriname, Venezuela), introduced in se Asia (se China, Indonesia), w Africa.
Discussion
Spigelia anthelmia is widely distributed in the subtropics and tropics. In Florida, it is restricted to Miami-Dade and Monroe counties. From Costa Rica to South America, it overlaps in range and is commonly confused with its close relative S. hamelioides Kunth (K. R. Gould 1997; A. V. Popovkin et al. 2011).
Selected References
None.