Spigelia marilandica

Herbs perennial, 30–60 cm; rhizomes stout. Stems 2 or 3, rarely branched. Cauline leaves: proximals 3 or 4 pairs per stem, sessile, blade usually ovate to lanceolate, sometimes elliptic, 4–12 × 1–5 cm, base rounded to cuneate; distals opposite. Cymes 4–17-flowered. Flowers: calyx lobes lanceolate-subulate, (5–)9–13 mm; corolla scarlet (rarely white) outside, yellow to greenish yellow (rarely pink) inside, tubular, narrow at base, gradually widening and inflated just below throat, 45–52 mm, lobes reflexed at anthesis. Capsules 5–6 × 8–9 mm. Seeds 3–4 mm. 2n = 48.

Phenology: Flowering (Mar–)May(–Jul).
Habitat: Rich, often circumneutral, soils, forest margins.
Elevation: 20–300 m.

Ala., Ark., Fla., Ga., Ill., Ind., Ky., La., Miss., Mo., N.C., Okla., S.C., Tenn., Tex.

Discussion

Despite the epithet, Spigelia marilandica is not known to occur in Maryland. The type specimen was allegedly collected in Virginia, where its occurrence is also not documented (T. Wieboldt, pers. comm.). It is closely related to both S. alabamensis and S. gentianoides (K. R. Gould and R. K. Jansen 1999; A. V. Popovkin et al. 2011) from which it is easily distinguished from the latter two species when in flower by its red and yellow (versus pink) corollas. Various alternate color forms of S. marilandica have been found throughout its range, including plants with white corollas outside (green inside), and scarlet corollas outside and pink or pink with red stripes inside. Spigelia marilandica overlaps S. gentianoides in distribution and may be confused with it when in vegetative state or in fruit; S. marilandica is a generally taller (30–60 cm versus 25–40 cm), more robust plant with stout (versus slender) rhizomes, longer (4–12 cm versus 2–4 cm) leaves that are equal to or longer (versus sometimes shorter) than the internodes with acuminate (versus acute to acuminate) apices, and generally has longer inflorescences with up to 17 (versus up to eight) flowers per cyme.

Selected References

None.

Lower Taxa