Russelia equisetiformis
Linnaea 6: 377. 1831.
Stems striate, sometimes rooting at tips, 4–12-angled, 7–15 dm, gland-dotted. Leaves dimorphic; proximal: petiole 3–4 mm, in whorls of 3–6, blade ovate, 8–15 × 6–10 mm, margins dentate, surfaces glandular-punctate; distal: petiole 0–1 mm, opposite or whorled, blade narrowly triangular, needlelike or scalelike, 1–2 × 1 mm, margins entire. Inflorescences 2-flowered; peduncles 3–4 cm. Pedicels 10–15 mm. Flowers: calyx lobes 2–3 mm, apex acute or mucronate; corolla 15–25 mm, glabrous, adaxial lip deeply notched; stamens 15–20 mm; staminode 0.5–0.7 mm, sometimes with an abortive anther. Capsules globular, 3–6 mm; style persistent. Seeds 0.3–0.4 mm, pitted. 2n = 20.
Phenology: Flowering year-round.
Habitat: Disturbed pinelands, palmetto scrub, old gardens.
Elevation: 0–100 m.
Discussion
Russelia equisetiformis is distinguished by its tubular, red corollas and arching, ridged, striate stems with relatively small distal leaves. It has been in cultivation since the eighteenth century and is sometimes grown as an annual in temperate areas.
Selected References
None.