The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

epiphytic flatsedge

flatsedge

Habit Herbs, perennial, cespitose, rhizomatous. Herbs, perennial, cespitose, rhizomatous.
Culms

trigonous, compressed, 15–75 cm × 0.5–3 mm, glabrous.

trigonous, base thickened, tuberous, 15–40 cm × 2–2.6 mm, glabrous.

Leaves

1–3, 5–30 cm × 1–2 mm.

flat to V-shaped, 10–30 cm × (3–)4–5.8 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.

spike 1, densely oblong to ellipsoid, 10–20 × 10–20 mm;

rays 4–12, 10–20 cm bracts 3–6, horizontal to ascending at 30°, V-shaped, 3–15 cm × (3–)4(–5.8) mm;

rachilla deciduous, wings persistent, 0.5–0.7 mm wide.

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.

(5–)10–20(–30), linear to oblong, quadrangular, (2.2–)4–12(–16) × 0.7–1.2 mm, densly packed on rachis with 11–21 spikelets per 5 mm rachis;

distal spikelet spreading or ascending;

floral scales persistent, 1–5, appressed, laterally whitish to reddish brown, medially green, narrowly oblong to ovate, laterally 3–6-ribbed, 2.4–3.4 × 1.6–2 mm, apex rounded to ± acute, entire, mucronate, mucro 0.1–0.3 mm;

sterile terminal scale, involute, only 0.4–0.6 mm wide with mucro 0.2–0.5 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.

anthers (0.3–)0.4–0.7 mm;

styles 0.4–0.5 mm;

stigmas 0.5–0.9 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.

light brown, sessile to slightly stipitate, ellipsoid to narrowly ellipsoid to narrowly obovoid, 1.4–1.9 × 0.5–0.75 mm, apex slightly apiculate, surfaces puncticulate.

Cyperus lanceolatus

Cyperus pseudothyrsiflorus

Phenology Fruiting summer. Fruiting mid summer–early fall (Jul–Sep).
Habitat Marshes Damp, disturbed soils, croplands
Elevation 0–100 m (0–300 ft) 0–1000 m (0–3300 ft)
Distribution
from FNA
AL; FL; GA; LA; TX; Mexico; Central America; South America; Africa
[WildflowerSearch map]
[BONAP county map]
from FNA
TX; Mexico
[BONAP county map]
Source FNA vol. 23, p. 162. FNA vol. 23.
Parent taxa Cyperaceae > Cyperus > subg. Pycreus Cyperaceae > Cyperus > subg. Cyperus
Sibling taxa
C. acuminatus, C. aggregatus, C. alopecuroides, C. amabilis, C. articulatus, C. bipartitus, C. cephalanthus, C. compressus, C. croceus, C. cuspidatus, C. dentatus, C. dentoniae, C. diandrus, C. difformis, C. digitatus, C. dipsaceus, C. distans, C. distinctus, C. drummondii, C. echinatus, C. elegans, C. entrerianus, C. eragrostis, C. erythrorhizos, C. esculentus, C. fendlerianus, C. filicinus, C. filiculmis, C. filiformis, C. flavescens, C. flavicomus, C. floribundus, C. fugax, C. fuligineus, C. fuscus, C. giganteus, C. gracilis, C. granitophilus, C. grayi, C. grayoides, C. haspan, C. hermaphroditus, C. houghtonii, C. hypopitys, C. hystricinus, C. involucratus, C. iria, C. laevigatus, C. lancastriensis, C. lecontei, C. lentiginosus, C. ligularis, C. lupulinus, C. manimae, C. microiria, C. mutisii, C. niger, C. ochraceus, C. odoratus, C. onerosus, C. ovatus, C. owanii, C. oxylepis, C. pallidicolor, C. papyrus, C. parishii, C. pilosus, C. planifolius, C. plukenetii, C. polystachyos, C. prolifer, C. prolixus, C. pseudothyrsiflorus, C. pseudovegetus, C. pumilus, C. reflexus, C. refractus, C. retroflexus, C. retrofractus, C. retrorsus, C. rotundus, C. sanguinolentus, C. schweinitzii, C. serotinus, C. seslerioides, C. setigerus, C. spectabilis, C. sphacelatus, C. sphaerolepis, C. squarrosus, C. strigosus, C. surinamensis, C. tetragonus, C. thyrsiflorus, C. virens
C. acuminatus, C. aggregatus, C. alopecuroides, C. amabilis, C. articulatus, C. bipartitus, C. cephalanthus, C. compressus, C. croceus, C. cuspidatus, C. dentatus, C. dentoniae, C. diandrus, C. difformis, C. digitatus, C. dipsaceus, C. distans, C. distinctus, C. drummondii, C. echinatus, C. elegans, C. entrerianus, C. eragrostis, C. erythrorhizos, C. esculentus, C. fendlerianus, C. filicinus, C. filiculmis, C. filiformis, C. flavescens, C. flavicomus, C. floribundus, C. fugax, C. fuligineus, C. fuscus, C. giganteus, C. gracilis, C. granitophilus, C. grayi, C. grayoides, C. haspan, C. hermaphroditus, C. houghtonii, C. hypopitys, C. hystricinus, C. involucratus, C. iria, C. laevigatus, C. lancastriensis, C. lanceolatus, C. lecontei, C. lentiginosus, C. ligularis, C. lupulinus, C. manimae, C. microiria, C. mutisii, C. niger, C. ochraceus, C. odoratus, C. onerosus, C. ovatus, C. owanii, C. oxylepis, C. pallidicolor, C. papyrus, C. parishii, C. pilosus, C. planifolius, C. plukenetii, C. polystachyos, C. prolifer, C. prolixus, C. pseudovegetus, C. pumilus, C. reflexus, C. refractus, C. retroflexus, C. retrofractus, C. retrorsus, C. rotundus, C. sanguinolentus, C. schweinitzii, C. serotinus, C. seslerioides, C. setigerus, C. spectabilis, C. sphacelatus, C. sphaerolepis, C. squarrosus, C. strigosus, C. surinamensis, C. tetragonus, C. thyrsiflorus, C. virens
Synonyms C. densus, C. humboldtianus, C. lanceolatus var. compositus, Pycreus densus C. uniflorus var. pseudothyrsiflorus
Name authority Poiret: in J. Lamarck et al., Encycl. 7: 245. (1806) (Kükenthal) J. Rich. Carter & S. D. Jones: Rhodora 99: 330. (1998)
Web links