Cyperus hermaphroditus |
Cyperus dentoniae |
|
---|---|---|
hermaphrodite flatsedge |
Denton's flatsedge, hairy flatsedge |
|
Habit | Herbs, perennial, rhizomatous. | Herbs, perennial, cespitose, shortly rhizomatous. |
Culms | trigonous, (10–)30–80(–140) cm × (0.4–)1–3(–5) mm, glabrous. |
1–4, trigonous, (2–)20–50(–80) cm × (0.8–)1.5–2(–2.8) mm, basally glabrous or nearly so, apically hispidulous, on faces and angles distally, especially so immediately proximal to bracts. |
Leaves | V-shaped or flanged V-shaped, (5–)15–70(–90) cm × (2–)4–10(–13) mm, glabrous. |
2–5(–7), V-shaped, (5–)15–30(–45) cm × (1.5–)2.5–5(–8) mm. |
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. |
spike 1 (occasionally 1–2 smaller sessile spikes at base), densely cylindric, (7–)11–20(–25) × (5–) 7–10(–12) mm; rays 3–6(–10), (1–)3–6(–18) cm, rays and rachis hispidulous; bracts 4–8(–10), ascending at 30–60°, V-shaped, (2–)10–25(–45) cm × (1–)3–6(–8) mm; rachilla deciduous, wings persistent, 0.3–0.4 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–)70–120(–140), oblong-ellipsoid to oblong-lanceoloid, ± terete to quadrangular, (2.2–)3.4–4.5(–5.6) × (0.8–)0.9–1.2(–1.3) mm; distal spikelet spreading or ascending; floral scales 1(–3), appressed, stramineous, red-spotted, strongly 3(–4)-ribbed on either side of green part, medially weakly 3-ribbed, ovate to elliptic ovate, (2.4–)2.8–3.3(–3.6) × 1.6–2 mm, apex acute, mucronulate from excurrent midrib. |
Flowers | anthers (0.4–)0.6–1 mm; styles 0.4–1.6 mm; stigmas 1–1.5 mm. |
anthers (0.3–)0.4–0.6 mm; styles 0.4–0.6(–0.8) mm; stigmas 1–1.4 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. |
brown, stipitate, ellipsoid, (1.6–)1.8–2 × (0.7–) 0.8–0.9 mm, stipe 0.1–0.2 × 0.2 mm, apex ± truncate, apiculate, surfaces puncticulate to glabrous. |
Cyperus hermaphroditus |
Cyperus dentoniae |
|
Phenology | Fruiting summer–fall. | Fruiting mid summer–fall (Jul–Sep). |
Habitat | Arroyos | Various dry, open environments |
Elevation | 500–1200 m (1600–3900 ft) | 500–1000 m (1600–3300 ft) |
Distribution |
AZ; TX; Mexico; South America; West Indies |
AZ; Mexico; Central America; South America |
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.) |
Cyperus dentoniae was not treated in G. Kükenthal’s monograph (1935–1936), apparently because he did not see any materials of the species. The plant has been treated as “C. asper (Liebmann) O’Neill,” a name based on Mariscus asper Liebmann and a synonym of C. mutisii (A. B. Ayers 1946). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 186. | FNA vol. 23, p. 187. |
Parent taxa | Cyperaceae > Cyperus > subg. Cyperus | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | Carex hermaphrodita, Mariscus hermaphroditus, Mariscus jacquinii | Mariscus pubescens, C. flavomariscus var. peduncularis, C. flavus var. peduncularis |
Name authority | (Jacquin) Standley: Contr. U.S. Natl. Herb. 18: 88. (1916) | G. C. Tucker: Syst. Bot. Monogr. 2: 56. (1983) |
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