Cyperus prolixus
in A. von Humboldt et al., Nov. Gen. Sp. 1: 206. 1816.
Herbs, perennial; rhizomes 3–20 cm × 1–2 cm, indurate. Culms stoutly trigonous, thickened, 50–300 cm × 5–30 mm, basally indurate, glabrous. Leaves V-shaped, with cross ribs, 40–130 cm × 10–15 mm, margins and keel scabrid. Inflorescences: spikes appressed-ascending, narrowly cylindric, (2–)3–45 mm × (4–)7–10 mm; rays (5–)9–12, 2–22(–30) cm; 2d order rays distinctly flattened, 1–10 cm; 3d order rays flattened, 0.5–3 cm; rachis 2.5–4 cm; bracts (6–)9–10, ascending at 45–75°, V- or inversely W-shaped, (5–)15–90 cm × 0.5–20 mm; rachilla persistent, wings 0.2–0.4 mm wide. Spikelets (4–)10–35, appressed-ascending, compressed, linear, 7–12(–15) × 0.6–1.2 mm; floral scales deciduous, 6–20, marginally clear, laterally brown, medially green, laterally 2–3-ribbed, medially 1-ribbed, oblong-ovate, (3.2–) 3.8–4.3 × 1.2–1.7 mm, apex spreading, acute to obtuse, mucronulate. Flowers: anthers 0.7–0.9 mm, connective apex bright red, oblong, to 0.1 mm; styles 0.8–1.3 mm; stigmas 2–3.3 mm. Achenes brown, sessile, narrowly ellipsoid, 1.8–2.5 × 0.8–1.3 mm, apex ± acute, not apiculate, surfaces puncticulate.
Phenology: Fruiting summer.
Habitat: Coastal marshes
Elevation: 0–10 m
Distribution
La., Mexico, Central America, South America.
Discussion
Cyperus prolixus produces large plants, similar in habit to C. giganteus and C. papyrus but easily distinguished by flattened rays.
Selected References
None.