Cyperus floribundus

(Kükenthal) J. Rich. Carter & S. D. Jones

Rhodora 99: 330. 1998.

Illustrated
Basionym: Cyperus uniflorus var. floribundus Kükenthal in H. G. A. Engler, Pflanzenr. 20[IV,101]: 521. 1936 Cyperus uniflorus Torrey & Hooker 1836
Treatment appears in FNA Volume 23. Mentioned on page 186, 187.

Herbs, perennial, cespitose, rhizomatous. Culms trigonous, basally tuberous thickened, 15–40 cm × 1–2.5 mm, glabrous. Leaves flat to V-shaped, 10–30 cm × 1–2 mm. Inflorescences: spike 1, densely oblong to ellipsoid, 8–36 × 8–20 mm; rays 4–12, 10–20 cm; bracts 3–6, horizontal to ascending at 30°, V-shaped, 3–15 cm × (3–)4–5.8 mm; rachilla deciduous, wings 0.5–0.7 mm wide. Spikelets (5–)20–35(–60), linear to oblong, quadrangular; 4–12(–21) × 0.7–1.2 mm, base narrowed to 0.4–1 mm; floral scales persistent, 1–3(–5), appressed, laterally whitish to reddish brown, stramineous with reddish spots, medially green, laterally 3–6-ribbed (midrib distinctly scabrid at 30X), narrowly oblong to ovate, 2.6–4.8 × 1.6–2 mm; apex rounded to ± acute, entire, with mucro 0.3–0.5 mm; sterile terminal scale involute, 0.4–0.6 mm wide, uncinate; distal floral scales with cusp 0.6–1.9. Flowers: anthers 0.5–1.3 mm; styles 0.4–0.5 mm; stigmas 0.5–0.9 mm. Achenes light brown to reddish brown, sessile to slightly stipitate, narrowly ellipsoid, 1.8–2.4 × 0.6–0.8 mm, apex slightly apiculate, surfaces puncticulate.


Phenology: Fruiting mid summer–early fall (Jul–Sep).
Habitat: Damp, disturbed soils, croplands
Elevation: 0–1000 m

Discussion

Included previously in Cyperus retroflexus (or its synonym C. uniflorus), C. floribundus has a much narrower geographic range (southern Texas and northeastern Mexico) and differs in features of spikelet morphology (J. R. Carter and S. D. Jones 1997).

Selected References

None.

Lower Taxa

None.
... more about "Cyperus floribundus"
Gordon C. Tucker* +, Brian G. Marcks* +  and J. Richard Carter * +
(Kükenthal) J. Rich. Carter & S. D. Jones +
Cyperus uniflorus var. floribundus +  and Cyperus uniflorus +
Tex. +  and Mexico. +
0–1000 m +
Damp, disturbed soils, croplands +
Fruiting mid summer–early fall (Jul–Sep). +
Illustrated +
Undefined subg. Chlorocyperus +, Cyperus subg. Mariscus +  and Undefined subg. Papyrus +
Cyperus floribundus +
Cyperus subg. Cyperus +
species +