Microstachys corniculata
Fl. Brit. W. I., 49. 1859.
Herbs, to 0.5 m, sparsely to moderately hirsute. Stems erect. Leaves: stipules triangular to rounded, 0.2–0.4 mm; petiole 0.1–1.5 cm; blade 2–4.5 × 0.3–2 cm, base cuneate to cordate, margins serrulate with proximal teeth occasionally replaced by orbicular glands, apex acute to acuminate. Inflorescences: staminate portion on peduncle 1–2 mm, fertile part 0.5–1.5 cm, to 15 bracts and cymules, flowers 1–3 per bract; pistillate portion with 1 flower; bracts triangular, 0.2 mm, subtended by 2 stipitate glands to 0.2 mm diam. Pedicels 0–0.2 mm, pistillate to 1 mm in fruit. Staminate flowers: sepals red-purple to greenish yellow, ovate, 0.3–0.5 mm; stamens yellow; filaments 0.2–0.3; anthers 0.2 mm. Pistillate flowers green; sepals ovate, 0.2–0.5 mm; ovary bearing short horned appendages; styles 0.3–0.6 mm. Capsules subglobose, 3–4 mm diam.; horned appendages 2–3 per valve, to 1 mm. Seeds 3 × 2 mm; seed coat brown, warty; caruncle discoid, 0.5–0.8 mm diam., stipitate on projection of seed coat.
Phenology: Flowering and fruiting summer–fall.
Habitat: Dry, disturbed sandhills.
Elevation: 0–40 m.
Distribution
Introduced; Fla., Mexico, West Indies, Central America, South America.
Discussion
Microstachys corniculata is a weedy species that is adventive and becoming established in Hillsborough County. It has the potential to become broadly naturalized across subtropical parts of the United States. Because this species is widespread in the West Indies, including Cuba, a 1906 collection from Key West may represent a native occurrence.
Selected References
None.