Cyperus hypochlorus

Hillebr. (1888)

This name is accepted

Kingdom: Viridiplantae Phylum: Magnoliophyta Class/Clade: Monocots Order: Poales Family: Cyperaceae Genus: Cyperus

‘ahu‘awa [ahuawa]

Description

Key Characters:

Growth Form: Perennials with short, woody rhizomes clothed with dark reddish brown or purplish brown scales and their fibrous remnants.

Stems: culms stout, 50–130 cm tall, 5–16 mm in diameter near base, trigonous, smooth.

Roots:

Leaves: Leaves simple. Leaves several. Blades linear as long as or slightly longer than the culm, 3–15 mm wide. Blades coriaceous. Margins entire. Sheaths dark reddish brown. Stipules absent.

Flowers: Flowers in inflorescences umbelliform, compound or partially compound, moderately dense, 5–18 cm long, 7–25 cm wide, rays 6–12, spreading, 3–16 cm long, once branched, each branch with 2–4 secondary rays, spikes cylindrical to oblong–elliptic, 2.5–4 cm long, 1.2–2 cm wide, densely bearing numerous spikelets, bracteoles setaceous, shorter than to as long as the subtending lateral spikes; involucral bracts 5– 10, the lower ones much longer than the inflorescence and up to 12 mm wide; spikelets 3–8–flowered, widely spreading to slightly reflexed, linear-lanceoloid, subterete, slightly turgid, 6–16 mm long, 1.5– 2.5 mm wide, rachilla broadly winged; glumes green and often tinged pale yellowish brown, chartaceous with hyaline upper margins, oblong-lanceolate or oblong–elliptic, 3.5–5.5 mm long, 1.5–2.5 mm wide, laxly imbricate, suberect but those in upper part of spikelet weakly spreading, 7–nerved or 9–nerved, midnerve prolonged into a minute recurved mucro. Flowers bisexual (perfect). Corolla (petals) absent. Stamens 3. Ovary superior; style 5–6 mm long.

Fruit: Achenes oblong–ellipsoid; trigonous; 1.7–2 mm long; ca. 0.8 mm wide. Seeds 1; seed coat thin; free from pericarp; embryo basal; endosperm abundant.

Ploidy:

Habitat: Occurring in mesic to wet forest.

Elevation Range: 350–1,280 m.

Historical Distribution

Uses and Culture

USES

Natural History

Statewide Status

Endemic

Island Status

Kaua'i Endemic
O'ahu Endemic
Molokai Endemic
Maui Endemic
Hawai'i Endemic

Dispersal Agents


Pollinators

Bibliography

Name Published In: Fl. Hawaiian Isl.: 468 (1888)

Occurrences

SNo. Scientific Name Locality Habitat Basis of Record Recorded By Record Number Island Source Date
1 Cyperus hypochlorus Waimea District; Waialae Ridge and N side of ridge above falls Metrosideros-Acacia mixed mesic forest w/ Mariscus pennatiformis, Panicum nephelophilum, Diospyros, Charpentiera, Dianella, Dodonaea, Styphelia, Antidesma, Poa sandvicensis, Schiedea, Alsinidendron, endemic ferns are diverse in cool, shady gulchs. Preserved_Specimen Wood, K.R. 2369 Kauai BISH 1993-02-10
2 Cyperus hypochlorus Keawapilau Gulch Preserved_Specimen Welton, P. 631 Oahu BISH 1991-01-21
3 Cyperus hypochlorus Waimea District. Kawaiiki Ridge. South facing slope just below the ridge. Diverse Mesic Forest W/Acacia koa w/Metrosideros with Zanthoxylum, Dodonea, Dubautia, Kadua affinis, Syzgium, or ridges. Open upper hillside w/Dicranopteris patches, open large Dianella patch w/ Cyperus and grasses. Preserved_Specimen Tangalin, N. 3110 Kauai BISH 2012-04-13
4 Cyperus hypochlorus Makaha Ridge, off Makaha Rd In mesic forest. Preserved_Specimen Hobdy, R.W. 3587 Kauai BISH 1993-03-23
5 Cyperus hypochlorus Waimea District. Makaha, upper north fork, north facing slopes behind and east of kokio keokeo. Metrosideros-Acacia-Alphitonia montane mesic forest w/ Euphorbia atrococca, Myrsine lanaiensis, Dodonaea viscosa, Psychotria mariniana, Wikstroemia furcata, Diospyros sandwicensis, Kadua affinis, Coprosma waimeae, C. foliosa, Polyscias kavaiensis, Anti Preserved_Specimen Wood, K.R. 16669 Kauai BISH 2015-12-03
6 Cyperus hypochlorus Ridgeline in vicinity of Puu Kawiwi, Waianae Kai Forest Reserve Occasional, under a low Acacia-Metrosideros canopy. Preserved_Specimen Takeuchi, W.N. 17 Oahu BISH 1983-12-11
7 Cyperus hypochlorus Waimea District. Waimea Canyon, just southeast of Kukui peak. Acacia-Metrosideros lowland dry to mesic forest with Dodonaea viscosa, Leptecophylla tameiameiae, Hibiscus waimeae, Diospyros sandwicensis, Chrysodracon aurea (=C. stenophylla), Planchonella sandwicensis, Nestegis sandwicensis, Bobea brevipres, Sida Preserved_Specimen Wood, K.R. 16351 Kauai BISH 2015-03-05
8 Cyperus hypochlorus Waimea District. Makaha Valley. Diospyros-Acacia-Metrosideros montane mesic forest w/ Diospyros sandwicensis, D. hillebrandii, Alphitonia ponderosa, Pisonia sandwicensis, Dodonaea viscosa, Pleomele aurea, Psychotria mariniana, Kadua affinis, Coprosma waimeae, C. foliosa, Myrsine lan Preserved_Specimen Wood, K.R. 15889 Kauai BISH 2014-03-20