Jepson eFlora
Key to families | Table of families and genera

Key to Cyperaceae

View taxon page for Cyperaceae

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Flower, fruit enclosed in sac-like structure (perigynium); flowers unisexual

2. Perigynium open at tip ..... CAREX

2' Perigynium open on 1 side ..... KOBRESIA

1' Flower, fruit not enclosed in sac-like structure; flowers bisexual or some staminate

3. Flower bracts 2-ranked; spikelets generally flat

4. Inflorescence in leaf axils; leaves cauline; stem internodes hollow ..... DULICHIUM

4' Inflorescence terminal; leaves basal or basal and cauline; stem internodes solid or spongy with air cavities

5. Spikelets with >= 2 sterile proximal flower bracts; leaf sheaths ± black; inflorescence head-like ..... SCHOENUS

5' Spikelets with 0–1 sterile proximal flower bracts; leaf sheaths not ± black; inflorescence head-like to openly branched

6. Spikelets with 2–36 flower bracts, each bract subtending a bisexual flower; fruits 2–many per spikelet ..... CYPERUS

6' Spikelets with 2(3) flower bracts, proximal bract sterile or subtending a bisexual flower, distal sterile or subtending a staminate flower; fruits 1 per spikelet ..... KYLLINGA

3' Flower bracts spiraled (except Isolepis levynsiana); spikelets not flat (± flat in Isolepis levynsiana)

7. Flower stems generally with cauline leaves 0 (1–2 cauline in Schoenoplectus saximontanus)

8. Inflorescence bracts 0; spikelet 1; leaves 2, blade 0 or tooth-like, <= 1 mm; fruit tubercle generally present ..... ELEOCHARIS

8' Inflorescence bracts >= 1; spikelets >= 1; leaves 1–3, generally some clearly bladed; fruit tubercle 0

9. Flower bract (outer if 2) with >= 3 veins; stem <= 40 cm

10. Flower bract 1 per flower ..... ISOLEPIS

10' Flower bracts (1)2 per flower (a 2nd, inner bract between flower, spikelet axis generally present) ..... LIPOCARPHA

9' Flower bract with 1 vein, at least in distal-most part of spikelet; stem <= 400 cm

11. Stems <= 15 cm, < 1 mm diam; spikelets 1, 3–4.6 mm, 1.5–2.8 mm wide ..... TRICHOPHORUM

11' Stems (1)10–400 cm, <= 10 mm diam; spikelets 1–200, 3–23 mm, 2–7 mm wide

12. Ligule ciliate; stem, leaf air cavities 0; stem wiry; flower bracts shiny, in proximal part of spikelet 3–9-veined, at least in distal-most 1-veined, tip not notched ..... AMPHISCIRPUS

12' Ligule glabrous; stem, leaf generally with air cavities; stem rarely wiry; flower bracts dull, 1-veined, tip generally notched ..... SCHOENOPLECTUS

7' Flower stems with cauline leaves >= 1 (see also Schoenoplectus saximontanus)

13. Inflorescences generally > 1, terminal and generally >= 1 axillary

14. Flowers 10–50 per spikelet ..... SCIRPUS (2)

14' Flowers < 6 per spikelet

15. Stem 5–10 mm diam; leaf blades 5–10 mm wide, margins saw-toothed ..... CLADIUM

15' Stem <= 2 mm diam; leaf blades 0.5–5 mm wide, margins generally scabrous ..... RHYNCHOSPORA

13' Inflorescence 1, terminal

16. Leaf sheath tip margins scabrous or ciliate; stem, leaf blades glabrous or generally ± scabrous or puberulent

17. Leaf sheath tip ciliate, hairs >> 1 mm, soft ..... BULBOSTYLIS

17' Leaf sheath tip scabrous, hairs << 1 mm, stiff ..... FIMBRISTYLIS

16' Leaf sheath tip margins glabrous; stem, leaf blades glabrous or on keels or angles scabrous

18. Stem cylindric; perianth bristles 10–25, smooth, >> fruit ..... ERIOPHORUM

18' Stem 3-angled; perianth bristles 3–6(12), barbed, < to > fruit

19. Flower bracts puberulent (glabrous in age), tip notched, generally with curved awn often broken off; tubers durable ..... BOLBOSCHOENUS

19' Flower bracts glabrous, tip entire or sharp-pointed, awn 0 or minute; tubers 0

20. Inflorescence congested, head-like; perianth bristles > fruit ..... CALLISCIRPUS

20' Inflorescence openly branched with head-like clusters at branch tips; perianth bristles <= fruit ..... SCIRPUS (2)

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Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
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