Cyperaceae Juss.
Herbs, usually perennial, often rhizomatous. Stems usually solid, often 3-angled. Leaves usually linear, some or all often reduced to basal sheaths. Flowers hermaphrodite or unisexual, each in the axil of a glume (bracteole), arranged in spikelets; inflorescence various, a simple or compound irregular umbel or panicle, or a capitate cluster of spikelets or a solitary terminal spike; commonly with 1 to several setaceous to leaf-like involucral bracts. Perianth of bristles, scales, hairs or 0. Stamens 3-(2-1), rarely 4-6. Ovary superior, 1-locular; style-branches 2 or 3; ovule solitary. Fruit a nut, indehiscent. Cosmopolitan, c. 90 genera and c. 4000 spp.
† Treated in Vol. II.
Key
2
Rhachilla not produced beyond utricle; flowers usually in several spikes but occasionally in a solitary spike
Rhachilla produced beyond utricle into a hook; flowers in a solitary spike
UNCINIA†
6
Inflorescence usually bracteate, terminal but often apparently lateral; nut without persistent style-base
Inflorescence ebracteate, terminal and appearing so, nut crowned by enlarged persistent style-base
10
Stems terete; glumes spirally arranged
GAHNIA†
15
Leaves similar to stems, or reduced to basal sheaths
LEPIDOSPERMA†
![Fig. 26. CYPERACEAE, flowers; A: Cyperus. B-C: Scirpus; B with hypogynous bristles, C without bristles D-E: Carex; D male, E female, showing nut enclosed in utricle (split lengthwise). © All rights reserved. [Image: 26XC]](https://data.landcareresearch.co.nz/Image/26XC/SysPortalPreview)
