Cyperus lanceolatus |
Cyperus pumilus |
|
---|---|---|
epiphytic flatsedge |
low flatsedge |
|
Habit | Herbs, perennial, cespitose, rhizomatous. | Herbs, annual, cespitose. |
Culms | trigonous, compressed, 15–75 cm × 0.5–3 mm, glabrous. |
trigonous, 1–35 cm × 0.5–1 mm, glabrous. |
Leaves | 1–3, 5–30 cm × 1–2 mm. |
flat, 5–20 cm × 1–2 mm. |
Inflorescences | spikes 1(–2), ovoid, 5–23 × 9–21 mm; rays 2–3(–4), 0–15 mm; if rays absent, head single, compact, sessile, (12–)15–20 mm diam.; bracts 2–3, horizontal to vertical, 2–14 cm × 0.5–3.5 mm. |
heads ± digitate, 8–26 mm diam.; rays 1–6, 0.5–5 cm; bracts 3–4, ± horizontal, flat, 3–18 cm × 1–2 mm. |
Spikelets | 1–6, oblong-lanceoloid, 5–26 × 2–3 mm; floral scales 12–54, closely imbricate, laterally yellowish brown, medially pale brown, occasionally greenish, laterally 1-ribbed, medially 3-ribbed, distinctly 2-keeled basally, ovate, 1.8–2.6 × 1.4–1.7 mm, apex obtuse. |
6–25, ovoid to linear-lanceoloid, compressed, 4–15 × 1–2 mm; floral scales 8–28(–40), clear, laterally ribless, ovate, 1.4–1.6 × 0.8 mm, apex awned, awn excurved, 0.3–0.5 mm. |
Flowers | stamens 2; anthers 0.4–0.5 mm, connectives not prolonged; styles 0.3–1 mm; stigmas 0.6–0.8(–1) mm. |
stamens 1–2; anthers 0.2 mm; styles 0.5 mm; stigmas 0.3 mm. |
Achenes | brown, network of ridges forming isodiametric or square cells, stipitate, obovoid to ellipsoid, 1.1–1.3 × (0.5–)0.6 mm, apex acute to broadly rounded, surfaces minutely punctate or finely papillose. |
dark brown to black, sessile, obovoid, 0.6 × 0.4 mm, apex obtuse, apiculate, surfaces minutely punctate. |
Cyperus lanceolatus |
Cyperus pumilus |
|
Phenology | Fruiting summer. | Fruiting spring–summer. |
Habitat | Marshes | Disturbed, sandy soils |
Elevation | 0–100 m (0–300 ft) | 0–50 m (0–200 ft) |
Distribution |
AL; FL; GA; LA; TX; Mexico; Central America; South America; Africa
|
FL; Asia; Africa (including Madagascar); Indian Ocean Islands; Pacific Islands; Australia [Introduced in North America; West Indies (introduced)] |
Discussion | Cyperus pumilus is distinctive because it is our only distigmatic Cyperus with awned floral scales. Cyperus hyalinus Vahl, a southeastern Asian and Australian species, has recently been collected in Miami-Dade County, Florida (Mears s.n., EIU, VSC). This is an aberrant species sometimes placed in the monotypic genus Queenslandiella as Q. hyalina (Vahl) F. Ballard; it differs from C. pumilus in having deciduous rachillae as well as deciduous floral scales. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 23, p. 162. | FNA vol. 23, p. 163. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycreus | Cyperaceae > Cyperus > subg. Pycreus |
Sibling taxa | ||
Synonyms | C. densus, C. humboldtianus, C. lanceolatus var. compositus, Pycreus densus | C. leucolepis, Juncellus leucolepis, Pycreus pumilus |
Name authority | Poiret: in J. Lamarck et al., Encycl. 7: 245. (1806) | Linnaeus: Cent. Pl. II, 6. (1756) |
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