Annual or perennial, rhizomatous or stoloniferous, rooting from lower nodes, sometimes floating. Leaf blade expanded or rolled, linear; ligule a fringed membrane to a fringe of hairs. Inflorescence an elongated, secund, false spike consisting of several sessile, spike-like, 1-sided racemes scattered singly on alternate sides and +/- appressed to long central axis; rachis triquetrous or winged, usually ending in an inconspicuous point; spikelets solitary or paired, often in 2 rows, sessile or very shortly pedicelled; abaxial (upper) glume turned away from rachis. Spikelet ovate, dorsiventrally compressed, falling with glumes; glumes unequal, awnless; lower glume a small membranous scale, 1-5-nerved; upper glume up to two-thirds as long as spikelet, 3-11-nerved, membranous. Florets 2; lower floret male or sterile; lemma membranous, +/- oblong-elliptic, rounded dorsally, subacute, 5-7-nerved, awnless; palea thinly membranous, equalling lemma; upper floret bisexual; lemma firmer than glumes, broadly elliptic, rounded dorsally, almost as long as spikelet, glabrous, rugose, entire, margins inrolled and clasping edges of palea, awnless; palea elliptic-lanceolate, acute, tip often briefly reflexed, flat and 2-keeled with margins involute, indurated. Lodicules 2, broadly cuneate, fleshy. Stamens 3. Ovary glabrous; styles connate at base, plumose. Caryopsis ellipsoid, dorsiventrally compressed. x= 9 (polyploidy).
Species +/- 40, warmer regions of both hemispheres; 2 in sthn Afr., N Namibia and Botswana, northern provinces of South Africa and KwaZulu-Natal.
Annual or perennial (short-lived), loosely tufted. Leaf blade linear-lanceolate, expanded, acute, margins often fringed with bristle-like hairs; ligule an unfringed to fringed membrane. Inflorescence a solitary, cylindrical, terminal spike or spike-like raceme, appearing plumose or like a bottle-brush because of long capillary glume awns; spikelets solitary, subsessile to pedicelled. Spikelet small, 1.2-5.5 mm long, laterally compressed, falling with glumes; glumes +/- equal, membranous, linear or linear-lanceolate, similar, 1-nerved, keeled, finely scabrid, awned; awn capillary, much longer than glumes. Floret 1, bisexual; lemma much shorter than glumes, less firm than glumes, hyaline, lanceolate, acute, 1-nerved, glabrous, awnless; palea very small, hyaline, nerveless. Lodicules 2, broad, cuneate. Stamens 3. Ovary +/- ellipsoid, glabrous; styles short, united at base, plumose. Caryopsis linear-lanceolate, almost as long as glumes at maturity. x= 10 (9) (polyploidy).
Species +/- 10, Africa to Asia and Australia; 3 in sthn Afr., N Namibia, Botswana, northern provinces of South Africa, Swaziland and KwaZulu-Natal.
Perennial, robust, tall reed, long-rhizomatous. Leaves cauline; leaf blade long, linear-lanceolate to lanceolate, expanded or inrolled from margins, deciduous at base of blade or at base of leaf sheath; ligule a fringed membrane or a fringe of hairs. Inflorescence a large, drooping, densely plumose panicle, open or contracted; spikelets solitary, pedicelled. Spikelet laterally compressed, disarticulating above glumes; glumes very unequal, shorter than spikelet, membranous, 3-5-nerved, acuminate, subacute. Florets 3-11; lowermost floret male or sterile, usually 3-nerved, acuminate, awnless; succeeding florets bisexual or rarely uppermost reduced; lemma decreasing in size upwards, similar in texture to glumes, membranous, linear-lanceolate, 1-3-nerved, glabrous but enveloped by long, silky hairs from callus, finely acuminate or tapering into an awn; awn straight, shorter than body of lemma; callus long, slender, blunt, hairy with long, silky hairs; palea shorter than lemma, oblong, linear-oblong or ovate-lanceolate; obtuse, 2-keeled, membranous or subhyaline. Lodicules 2. Stamens 3, sometimes 2 in lowest male floret, if present. Ovary glabrous; style distinct, stigma plumose. x= 12 (aneuploids, high polyploidy).
Species +/- 3, cosmopolitan; 2 in sthn Afr., widespread in aquatic or semi-aquatic habitats.
Annual or perennial, tufted, rhizomatous, sometimes geniculate. Leaf blade linear to linear-lanceolate, expanded; ligule a conspicuous, unfringed membrane. Inflorescence a dense, oblong or spike-like panicle, sometimes subcapitate or interrupted and lobed, ( P. paradoxa: 1 fertile spikelet surrounded by 5 or 6 sterile spikelets, these often reduced to clavate knobs; the whole falling as a unit); spikelets shortly pedicelled. Spikelet strongly laterally compressed, disarticulating above glumes; glumes +/- equal, completely enclosing lemma, membranous, boat-shaped, almost plano-convex in outline, subobtuse, 3-nerved, strongly keeled, keels often winged and toothed. Florets 3, lowest 2 florets sterile, reduced to rudimentary lemmas, varying from very small to more than half as long as upper lemma, glabrous; uppermost floret bisexual; lemma firmer than glumes, chartaceous, ovate-elliptic or ovate-lanceolate, usually softly hairy, 5-nerved, obtuse or acute, awnless; palea relatively long, keelless. Lodicules 2, membranous, hyaline. Stamens 3. Ovary ellipsoid; styles distinct, plumose. Caryopsis ellipsoid. x= 6, 7 (aneuploids, high polyploidy).
Species +/- 16, north temperate, but mostly from Mediterranean region, also South America; 6 in sthn Afr., widespread weeds or escapes from cultivation.
Annual or perennial, tufted or decumbent, sometimes rhizomatous, stoloniferous, sometimes geniculate. Leafblade expanded, rolled or folded; apex often boat-shaped; ligule an unfringed or rarely a fringed membrane. Inflorescence a panicle, open and often effuse or contracted; spikelets solitary, pedicelled, pedicels swollen at apex. Spikelets 3-6 mm long, laterally compressed, disarticulating above glumes, sometimes viviparous; glumes usually +/- equal, rarely unequal, shorter than spikelet, similar, membranous, ovate or oblong, acute to obtuse, with median keel, awnless, mucronate or rarely awned; lower glume 1-3-nerved; upper glume usually 3-nerved. Florets 2-6, bisexual or uppermost reduced; lemmas decreasing in size upwards, similar in texture to glumes, membranous, lanceolate or oblong, obtuse or subacute, 5-7(-11)-nerved, entire, median-keeled, keel glabrous or hairy, especially towards base, usually awnless, rarely mucronate or awned; callus often with long woolly hairs; palea subequalling lemma, 2-keeled, thinner in texture than lemma. Lodicules 2, +/- 2-lobed. Stamens 3. Ovary glabrous; styles distinct, plumose. Caryopsis ellipsoid to ovoid. x= 7 (aneuploids, high polyploidy).
Species +/- 500, cosmopolitan; 6 in sthn Afr., widespread.
Pedicelled spikelet slightly smaller than sessile spikelet, male or sterile, falling separately, pedicel oblong, scarcely distinguishable from internode, compressed. x= 9, 10 (polyploidy).
Species 4, tropical and subtropical Africa and Asia; 1 in sthn Afr.: Rottboellia cochinchinensis (Lour.) Clayton, northern districts of Namibia, N Botswana, Northern Province, Mpumalanga and N KwaZulu-Natal.
Annual or perennial, of various habit. Leaf blade linear-lanceolate or long-linear, expanded or rolled; ligule an unfringed or a fringed membrane or a fringe of hairs. Inflorescence a panicle, open or rarely contracted; spikelets pedicelled. Spikelet lanceolate, oblong, elliptic or almost spherical, usually dorsiventrally compressed, usually falling with glumes; glumes unequal, rarely equal, membranous to hyaline, dissimilar or similar, usually awnless; lower glume usually shorter than spikelet, 0-7-nerved, awnless or minutely awned; upper glume as long as spikelet, 3-14-nerved. Florets 2; lower floret male or sterile; lemma very similar to upper glume, with or without a palea; upper floret bisexual, lemma similar to firmer in texture than glumes, usually becoming indurated, elliptic, ovate-elliptic or rarely oblong, obtuse or subacute, smooth or transversely rugose, glabrous, margins inrolled and clasping edges of palea, awnless; palea similar to and subequalling lemma, often with marginal flaps at base. Lodicules 2, broadly cuneate. Stamens 3. Ovary ellipsoid, glabrous; styles distinct, plumose above. Caryopsis +/- ellipsoid, dorsiventrally compressed. x= 7, 9, 10 (high polyploidy).
Species +/- 470, tropical, subtropical and warm temperate; 42 in sthn Afr., widespread.
Perennial, tufted, with woody culms; culm sheath blades narrow. Leaf blade linear-lanceolate to lanceolate, pseudopetiolated, expanded, deciduous from sheath. Inflorescence a dense, spiny, globose cluster of spikelets at tips of leafy branchlets, each spikelet cluster subtended by a short-bladed papery sheath, and individual spikelets subtended by several short papery bracts. Spikelet falling entire at maturity; glumes unequal, 17-30-nerved with cross-nerves connecting them. Florets 1-4; lower florets male or sterile; upper florets bisexual; lemma 11-23-nerved with cross-nerves, apically awned; palea 16-19-nerved. Lodicules usually 0. Stamens 6; filaments united. Ovary glabrous; apical appendage long, stiff and tapering. x= 12 (polyploidy).
Species 1, Africa: Oxytenanthera abyssinica (A.Rich.) Munro, specimens from Northern Province resemble this species vegetatively but until flowering material is obtained the identification will remain tentative.
Annual or perennial, tufted, stoloniferous, rhizomatous. Leaf blade narrow-linear, expanded, folded or rolled; ligule a fringed membrane or a fringe of hairs. Inflorescence a solitary, terminal, cylindrical to subglobose spike-like panicle, branches short or reduced to stumps, rarely axillary, then gathered into a leafy false panicle, or 2-4 spikelets enclosed in uppermost sheath ( P. clandestinum); spikelets subtended by an involucre of filiform or slender, glabrous, scabrid or plumose, rarely solitary bristles, free to base, falling with spikelets at maturity (except in cultivated forms); spikelets solitary or in clusters of 2-5, outer often reduced, sessile or shortly pedicelled. Spikelet narrowly lanceolate to oblong, dorsiventrally compressed to subterete; glumes unequal, awnless; lower glume up to half as long as spikelet, sometimes suppressed, thinly membranous, nerveless or 1-5-nerved; upper glume very small to as long as spikelet, 1-11-nerved. Florets 2; lower floret male or sterile; lemma lanceolate or ovate-lanceolate, membranous, of variable length, acuminate, acute, 1-15-nerved, awnless or awned; palea well developed or reduced or 0; upper floret bisexual; lemma as long as or little shorter than spikelet, similar to firmer than glumes, membranous to thinly coriaceous, entire, 5-7-nerved, flat, thin margins covering +/- half of palea, mucronate to awned; palea subequal and similar in texture to lemma, 2-nerved. Lodicules small, 2 or 0. Stamens 3; tips of anthers glabrous or minutely penicillate. Ovary ellipsoid; style distinct or connate below. Caryopsis oblong and dorsiventrally compressed to subglobose. x= 9 (aneuploids, polyploidy).
Species +/- 80, cosmopolitan in tropical and warm regions; 14 in sthn Afr., widespread.