Spigelia texana
Prodr. 9: 5. 1845.
Herbs perennial, (10–)20–45(–50) cm; rhizomes slender. Stems 1–3, seldom branched. Cauline leaves: proximals 2 or 3 pairs per stem, attenuate-petiolate; petiole 3 mm; blade ovate, lanceolate, oblong-elliptic, elliptic, or rhombic, 3–5.5 × 0.9–1.7 cm, base narrowly cuneate; distals usually pseudowhorled. Cymes 2-flowered. Pedicels 1–3 mm. Flowers: calyx lobes linear-lanceolate, 2–5 mm; corolla white, suffused with pink or yellow and with 2 pale lavender lines on each lobe outside, white inside, funnelform, 8–11(–13) mm, lobes spreading at anthesis. Capsules 2–3 × 4–5 mm. Seeds 1–2 mm.
Phenology: Flowering Apr–Jul.
Habitat: Black-clay soils in thickets, woods along streams, riparian forests.
Elevation: 0–500 m.
Discussion
Spigelia texana, of eastern Texas, is most closely related to S. hedyotidea of central-western Texas and northern to central Mexico (K. R. Gould and R. K. Jansen 1999). It can be distinguished from S. hedyotidea by its taller growth habit, its larger, more membranaceous leaves that dry flat (versus coriaceous and drying wrinkled), its tendency to be glabrous throughout, except at the nodes where stiff papillae occur (versus scabrous throughout), its tendency to produce a pseudowhorl of four leaves (versus paired) that subtend the inflorescence, and its slightly wider corollas.
Selected References
None.