Flora of New Zealand Series

Type species: P. dimidiatum L.

Perennials, of various habit. Leaf-sheath open or closed below. Ligule membranous, glabrous. Collar often bearded. Leaf-blade flat or convolute, rolled in bud. Culm simple or branched. Inflorescence paniculate, of spike-like racemes, these solitary, digitate or scattered along a simple common rachis. Racemes bearing subsessile to short-pedicelled, ± appressed, single or paired spikelets in two rows along one side of narrow or wing-like rachis. Spikelets lanceolate to oblong or orbicular, awnless, dorsally compressed, usually planoconvex, falling entire at maturity, 2-flowered, florets awnless; lower floret Ø, reduced to a lemma; upper floret ⚥. Glumes membranous; lower usually 0, rarely a small scale, upper ≈ spikelet. Lower floret: lemma similar in size and texture to upper glume but less convex, or flat; palea 0 or vestigial. Upper floret: lemma ± crustaceous, glabrous, usually obtuse with firm inrolled margins; palea ≈ lemma and similar in texture; lodicules 2, minute, broadly cuneate, rather fleshy; stamens 3; ovary apex glabrous, styles subterminal, free; caryopsis ± biconvex, embryo < ½ length of caryopsis, hilum subbasal, punctiform.

c. 250 spp. of tropical and warm temperate regions. Naturalised spp. 6; transient spp. 2.