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Photo is of parent taxon
Habit Plants annual; rhizomes 1 mm diam.
Culms

cylindric, ridged when dry, 0.05–0.5 m × 0.5–1 mm.

Leaves

3–4, 1 cauline, nearly equaling culm;

sheaths disintegrating to fibers;

blades 1–2, thickly C-shaped in cross section, distally flat, from much shorter to ca. 1/2 as long as sheath, 0–200 × 0.2–1 mm, smooth or margins distally spinulose.

Inflorescences

capitate or of 1 spikelet or rarely with 1 or 2 branches to 3 cm;

proximal bract erect, resembling leaf blades, 5–200 mm.

Spikelet(s)

achenes blackish brown when ripe, unequally biconvex to obscurely trigonous, adaxial surface longitudinally convex and horizontally concave with a convex center, ovoid to obovoid, 1–1.6 × 1–1.5 mm, with 12–15 sharp to blunt ridges;

beak 0.1 mm.

Flowers

perianth absent;

anthers 0.5 mm;

styles 2-fid or rarely few 3-fid.

Amphicarpic

achenes thickly trigonous with rounded abaxial faces, ellipsoid, prominently beaked, 2.2–3.2 mm, rugose.

2n

= 10.

Schoenoplectus erectus subsp. raynalii

Phenology Fruiting summer–fall, spring (Texas).
Habitat Wet soils or emergent, freshwater shores, temporary ponds, ditches, usually sandy and often drying areas
Elevation 0–100 m (0–300 ft)
Distribution
from FNA
AL; FL; GA; SC; TX; Mexico (Quintana Roo, Tamaulipas); South America (Argentina, Paraguay); Asia (Vietnam); Africa; Australia
Discussion

Many specimens of Schoenoplectus erectus subsp. raynalii are misidentified as Schoenoplectus hallii or S. saximontanus. North American Scirpus erismanae and S. wilkensii (A. E. Schuyler 1969) were placed in synonymy under Schoenoplectus erectus (J. Raynal 1976). North American plants are indistinguishable from eastern and southern African plants. Schoenoplectus erectus subsp. erectus differs in its “wrinkled” achenes with faint ridges and is reported only from Mauritius (the type locality), Madagascar, and associated islands. The name Scirpus erectus has long been misapplied in the Old World to Scirpus juncoides Roxburgh in the broad sense, which is related to S. purshianus and S. smithii in 7c. Schoenoplectus sect. Actaeogeton.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 23.
Parent taxa Cyperaceae > Schoenoplectus > sect. Supini > Schoenoplectus erectus
Synonyms Scirpus raynalii, Scirpus erismanae, Scirpus wilkensii
Name authority (Schuyler) Lye: Nordic J. Bot. 3: 243. (1983)
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