Flora of New Zealand Series

Type species: I. arundinacea Cirillo  nom. illeg.

Perennials, tufted from long, many-noded rhizomes, with leaves crowded at base. Leaf-sheath firm. Ligule membranous, ± ciliate. Leaf-blade long, flat, stiff, sometimes pseudopetiolate. Culm erect, unbranched, few-noded. Inflorescence a spike-like or narrowly branched silvery panicle; branches bearing numerous, usually paired, unequally pedicelled spikelets. Spikelets 2-flowered; lower floret usually reduced to a lemma, rarely ♂, upper floret ⚥. Glumes subequal, (0)-3-7-nerved, membranous, firmer below, enveloped by long silky hairs from very obtuse basal callus and lower portions of glumes. Lemmas 0-(1)-nerved, often < glumes, hyaline, awnless; lemma of lower floret ± broadly oblong, often denticulate; lemma of upper floret shorter, lanceolate to oblong, rarely 0. Palea broad, hyaline, nerveless, denticulate. Lodicules 0. Callus hairy. Rachilla not prolonged. Stamens 1-2 (in N.Z.)-3. Ovary glabrous; styles fused near base. Caryopsis oblong, loosely enclosed by lemma and palea; embryo ½-⅔ length of caryopsis; hilum elliptic, basal.

10 spp. in tropical and subtropical regions of both Hemispheres. Endemic sp. 1; naturalised sp. 1.