Hydrolea quadrivalvis
Fl. Carol., 110. 1788.
Herbs, erect or decumbent, to 6 dm, unbranched, with short reproductive branches or with branches arising from prostrate stems. Stems green to brown, with long, jointed hairs; thorns 1 or 2 per node, rarely absent, 5–12 × 0.6–1.2 mm. Leaf blades lanceolate, 4–10 × 1–2.5 cm, base attenuate to acute, margins entire or serrulate, surfaces hairy, with occasional long trichomes restricted to veins. Inflorescences axillary, fasciculate, 1–10-flowered, or on short, leafy branches. Flowers: sepals lanceolate, 6–10 × 1.5–2.5 mm, with long, jointed hairs; corolla blue, rarely white, petals 8–11 × 3.5–6 mm; ovary glabrous; styles 2, 3.5–5 mm, glabrous. Capsules globose, 5.5–7 × 5–7 mm, glabrous. Seeds cylindric, 0.6–0.7 × 0.2–0.3 mm. 2n = 20.
Phenology: Flowering Jul–Sep.
Habitat: Pond margins, stream banks and mudflats.
Elevation: 30–400 m.
Distribution
Ala., Fla., Ga., La., Miss., N.C., S.C., Tenn., Va.
Discussion
In morphology, Hydrolea quadrivalvis is closest to H. uniflora but differs in having long, jointed hairs on stems and sepals.
Selected References
None.