Lye, K.A. (1995) Cyperaceae in Flora of Somalia 4: 98-147
Plants usually perennial, sometimes annual, herbs, tufted, with creeping rhizomes of stoloniferous, sometimes producing tubers or bulbs; stems usually 3-angled, sometimes terete or 6-angled. Leaves 3-ranked, usually all basal or almost so, sometimes to midlength, usually linear and grasslike, sometimes lower scale-like and covering the stem base and rhizome, sometimes all leaves reduced to sheaths. Inflorescences terminal, often a somewhat umbel-like open anthela or congested and head-like, usually consisting of numerous spikelets set in distinct spikes or digitate clusters; involucral bracts usually similar to the leaves, the base of each branch (ray) enclosed in a tubular 2-keeled prophyll. Spikelets more or less compressed, linear or ovate, with 1-50 flowers; axes often winged by the decurrent base of the persisent of caducous glume bases; floret scales 2-ranked, white, grey, green, brown, reddish brown, or blackish, often variegated, with 1-5 more or less distinct veins on each side of the midrib; midribs often green or of another colour than the rest of the scale, sometimes excurrent and forming a short striaght or recurved mucro; flowers bisexual, without bristles or scales; stamens 3, 2, or 1, connectives often extending beyond the thecae; ovaries with 1 style; styles 3- or 2-fid, rarely almost undivided. Fruits nutlets, sessile, 3-angled or lenticular. usually obvoid or ellipsoid, surfaces often tuberculate or papillose.
Cyperus, as interpreted here, includes about 650 species. This is a broad interpretation. It includes about 300 species that are sometimes included in one of the many segregates that have been recognized.
