Cyperus hermaphroditus |
Cyperus aggregatus |
|
---|---|---|
hermaphrodite flatsedge |
ballast sedge, inflated-scale flatsedge |
|
Habit | Herbs, perennial, rhizomatous. | Herbs, perennial, cespitose, rhizomatous. |
Culms | trigonous, (10–)30–80(–140) cm × (0.4–)1–3(–5) mm, glabrous. |
trigonous, 20–100 cm × 0.8–2.5 mm, glabrous. |
Leaves | V-shaped or flanged V-shaped, (5–)15–70(–90) cm × (2–)4–10(–13) mm, glabrous. |
5–10, V-shaped to flanged V-shaped, 10–70(–90) cm × 2–7 mm, margins and midribs scabridulous or glabrous. |
Inflorescences | spikes 1(–5), rather densely ovoid or oblong-cylindric, (10–)25–45(–62) × 7–22 mm, 11–21 spikelets per 5 mm of rachis; rays (3–)5–10(–17), (1–)5–12(–24) cm; bracts (2–)4–8, ascending at 30–45°, V- or inversely W-shaped, (2–)8–40(–65) cm × (1–)2–8 mm; rachilla deciduous, wings 0.4–0.5 mm wide. |
spikes 1(–6), densely cylindric, 6–30 × 5–11 mm; rays 3–12, 0.4–5(–7) cm; rays and rachis glabrous; usually only 1–2 spikes of inflorescence on elongate rays, other spikes sessile or nearly so; bracts 4–7, horizontal to slightly ascending, 1–16 cm × 0.5–4 mm; rachilla deciduous, wings persistent, 0.5 mm wide. |
Spikelets | (10–)50–150, oblong to linear, quadrangular, (3–)4–8(–18) × (0.8–)1–1.2(–1.6) mm; distal spikelet spreading or ascending; floral scales (1–) 3–8, pale greenish white to golden brown, deep brown, or reddish brown, medially usually green, weakly to strongly 3(–4)-ribbed laterally, 1–3-ribbed medially, ovate to elliptic, (2–)2.6–3.2(–4) × 1.2–2 mm, apex obtuse. |
20–80, ellipsoid, roughly quadrangular, 3–5 × 1–1.4 mm; floral scales 1–2(–4), appressed, stramineous to golden brown, often red-speckled, medially greenish, 9-ribbed, elliptic to ovate, 2.4–3.4 × 1.8–2.6 mm, apex obtuse. |
Flowers | anthers (0.4–)0.6–1 mm; styles 0.4–1.6 mm; stigmas 1–1.5 mm. |
anthers 0.4–0.6 mm; styles 0.7–1.1 mm; stigmas 1.4–2.1 mm. |
Achenes | brown or reddish brown, sessile or nearly so, ellipsoid, 1.4–1.8(–2) × 0.6–0.8(–1) mm, apex acute to obtuse, slightly apiculate, surfaces puncticulate. |
dark brown to reddish brown, sessile, broadly ellipsoid, 1.8–2.1 × 0.8–1 mm, apex apiculate, surfaces glabrous to finely puncticulate. |
Cyperus hermaphroditus |
Cyperus aggregatus |
|
Phenology | Fruiting summer–fall. | Fruiting mid summer–fall (Jul–Oct). |
Habitat | Arroyos | Dry roadsides, pastures, thickets |
Elevation | 500–1200 m (1600–3900 ft) | 0–500 m (0–1600 ft) |
Distribution |
AZ; TX; Mexico; South America; West Indies |
AZ; LA; MS; NJ; NM; OR; PA; TX; Mexico; Central America; South America [Introduced, Australia]
|
Discussion | An erroneous report of Cyperus hermaphroditus from Alabama was based on misidentification of C. thyrsiflorus. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The records of Cyperus aggregatus in New Jersey, Oregon, and Pennsylvania represent introductions from ballast. The closely related Mexican and Central American Cyperus regiomontanus Britton has been collected once as an adventive or waif in southern California. It is distinguished from C. aggregatus by its silvery green, subulate-lanceolate spikelets and achenes that are only 0.4–0.6 mm wide. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 186. | FNA vol. 23. |
Parent taxa | Cyperaceae > Cyperus > subg. Cyperus | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | Carex hermaphrodita, Mariscus hermaphroditus, Mariscus jacquinii | Mariscus aggregatus, C. cayennensis, C. flavus, C. flavus var. aggregatus, C. flavus var. laevis, Kyllinga cayennensis, Kyllinga squarrosa, Mariscus flavus, Mariscus laevis |
Name authority | (Jacquin) Standley: Contr. U.S. Natl. Herb. 18: 88. (1916) | (Willdenow) Endlicher: Cat. Horti Vindob. 1: 93. (1842) |
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