Difference between revisions of "Cyperus mutisii"

Revision as of 21:07, 16 December 2019

Copyright: Flora of North America Association

Herbs, perennial, cespitose, rhizomatous. Culms trigonous, (20–)30–120 cm × 1.4–3.5 mm, glabrous or occasionally with scattered prickles on distal angles. Leaves 2–4(–6), inversely W-shaped, 10–60(–70) cm × (2–)4–13 mm, margins and midribs scabridulous or glabrous. Inflorescences: spikes (1–)3–6, narrowly cylindric, 1–4(–6) cm × 5–11 mm; rays 0 or 3–6, 2–23 cm; bracts 5–8, ascending at ± 45°, inversely W-shaped, (4–) 14–40(–46) cm × 1–12 mm; rachilla deciduous, wings persistent, 0.3–0.5 mm wide. Spikelets 35–100, oblong-ellipsoid, ± terete, elliptic in cross section, 3–7 × (0.9–) 1.3–2 mm; distal spikelets spreading or ascending; floral scales persistent, 1–2(–5), appressed, becoming clear at maturity, laterally brownish to reddish brown, medially greenish, laterally 3–5-ribbed, medially 3-ribbed, often erose at maturity, ovate to elliptic, 2.2–3.2 × 1.5–2.1 mm, apex obtuse. Flowers: anthers 0.6–0.8 mm; styles 0.4–0.8 mm; stigmas 1.2–2.2 mm. Achenes brown to reddish brown, sessile, broadly ellipsoid, slightly dorsiventrally flattened, 1.5–1.8 × 0.7–0.9(–1) mm, apex obtuse, apiculate, surfaces papillose to puncticulate.

Phenology: Fruiting summer–fall (Jun–Nov).
Habitat: Clearings in montane forests, canyons
Elevation: 500–1500 m

Ariz., Mexico, Central America, South America.

Discussion

Cyperus mutisii is recognized by its cylindric spikes borne digitately at the ends of the rays and its short, plump spikelets. As spikelets mature, the floral scales, having erose margins contrasting with the brownish sides, beome useful distinguishing features.

Selected References

None.

Lower Taxa