Herbs or small shrubs, erect or decumbent, to 20 dm, un­branched to broadly branched. Stems green, brown, or purple, pubescent or hispid-hirsute, oc­casionally glabrous, usually densely covered with short, glandular trichomes; thorns 1 or 2 per node or absent, 4–30 × 0.4–2 mm. Leaf blades ovate to lan­ceolate, oc­casionally linear, 1–12 × 0.2–3 cm, base atten­uate to acute, margins entire or serrulate, surfaces puberulent to hispid-hirsute, with or without glandular trichomes. Inflorescences terminal, narrow or broadly branching, leafy panicles or clustered at branch tips, 20–100-flowered. Flowers: sepals lanceolate, 6–14 × 1.5–3.5 mm, puberulent to hispid-hirsute, with glan­dular trichomes; corolla blue, rarely white, petals 5–17 × 2–12 mm; ovary puberulent, upper 1/2 usually glandular-pubescent; styles 2–4, 1.5–13 mm, glandular-pubescent toward bases. Capsules globose to ovoid, 3.5–8 × 3–7 mm, upper 1/2 puberulent or glandular-pubescent. Seeds ovoid to cylindric, symmetric, 0.4–0.7 × 0.2–0.3 mm. 2n = 20, 40.

Phenology: Flowering year-round.
Habitat: Wet pond margins, open flood plains.
Elevation: 0–10 m.

Distribution

• Generated Map
• Legacy Map

Tex., Mexico, Central America, South America (south to Argentina).

Discussion

In the flora area, var. spinosa is known from Cameron County. Specimens vary in pubescence, thorniness, and leaf shape and size.

Selected References

None.

Lower Taxa

None.