Herbs or small shrubs, erect, to 10 dm, usually broadly branched. Stems green to brown, densely pubescent, occasionally with few longer or glandular trichomes; thorns 1 or 2 per node, 5–12 × 0.3–0.8 mm. Leaf blades ovate, occasionally orbiculate, 1.5–7 × 1–2.5 cm, base atten­uate, acute, or obtuse, margins entire, surfaces pubes­cent. Inflorescences terminal, paniculate, leafy, broadly branching, 25–40-flowered. Flowers: sepals narrowly lanceolate, 6–9 × 1–2.5 mm, hispid-hirsute, with glan­dular trichomes; corolla blue, occasionally white, petals 11–17 × 5–9 mm; ovary glabrous or puberulent, upper 1/2 often with glandular trichomes; styles 2, 10–15 mm, glandular-pubescent toward bases. Capsules globose, 4.5–5.5 × 4–5.5 mm, upper 1/2 puberulent or glandular-pubescent. Seeds cylindric, symmetric, 0.5–0.6 × 0.2–0.3 mm. 2n = 20.

Phenology: Flowering Jun–Sep.
Habitat: Edges of sloughs, marshes, and ponds.
Elevation: 2–200 m.

Distribution

• Generated Map
• Legacy Map

Ala., Ark., Fla., Ga., Ky., La., Miss., Mo., Okla., Tenn., Tex.

Discussion

Hydrolea ovata is much more robust than H. corymbosa, with densely pubescent stems and leaves. Its leaves are ovate, while those of H. corymbosa are lanceolate.

Some forms of Hydrolea spinosa have small, rounded leaves similar to those of H. ovata; however, the stems of H. ovata are only rarely glandular-pubescent, and the styles are much longer than those of H. spinosa.

A number of specimens collected in Louisiana and eastern Texas appear to result from hybridization between Hydrolea ovata and H. uniflora. These are marked by several intermediate characteristics: leaves are ovate-lanceolate and sparsely pubescent; stems and sepals are also pubescent, with the latter sometimes glandular-pubescent; petals are either the same size as in one of the species or intermediate. The putative hybrids generally are extensively branched, with branches from the lower nodes producing a much bushier and more sprawling plant than is typical of either species. Clusters of flowers are borne either at the tips or at the nodes of these lateral branches.

Selected References

None.

Lower Taxa

None.