Chionochloa New Zealand J. Bot. 1: 87 (1963).
Derivation:. From the Greek chion (snow) and chloe (young green corn or grass), in reference to the common name - snow grasses.
Key references (keys and floras):. B.K.Simon, Key to Australian Grasses 84 (1993); S.W.L.Jacobs and S.M.Hastings, Flora of New South Wales 4: 558–559 (1993); N.G.Walsh, Flora Victoria 2: 522–524 (1994); E.Edgar and H.E.Connor, Flora of New Zealand 5: 423–459 (2000); D.Sharp and B.K.Simon, AusGrass (2002); S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th Ed, 182 (2008).
W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (264).
Native. 23 species, from New Zealand, southeastern Australia. 1 species in Australia, NSW and Vic.
Habit. Perennial, tufted. Leaf blades broad or narrow. Ligule a fringe of hairs.
Inflorescence. Inflorescence paniculate (usually hairy in the branch axils), open or contracted.
Spikelets. Spikelets laterally compressed, pedicelled; with naked rachilla extension, or with rachilla terminating in a floret. Fertile spikelets pale, golden or purpled, laterally compressed, disarticulating above glumes.
Glumes. Glumes unequal to more or less equal, shorter than spikelet to exceeding florets (but usually shorter), shorter than adjacent lemmas to long relative to adjacent lemmas, hairless (glabrous, occasionally prickle-toothed) or hairy (the upper, sometimes long-hairy on the lower margin), pointed, awned (rarely) or awnless, similar (membernous, the margins thin). Lower glume 1(–3) nerved. Upper glume 3 nerved or 5 nerved or 7 nerved.
Florets. Fertile florets 3–9. Lemmas membranous, incised, deeply cleft to not deeply cleft (the lateral lobes usually shorter than the body), awned, 7–9 nerved, not keeled. Awns 1 or 3, the median different in form from laterals (when laterals present), from a sinus, geniculate. Lateral awns shorter than median. Awn bases twisted or not twisted, flattened. Lemma hairs not in transverse rows (in vertical lines between the veins). Palea relatively long (exceeding the lemma sinus), usually apically notched, awnless, without apical setae (usually) or awned, 2 nerved, 2 keeled, glabrous or scabrous or hairy. Palea keels hairy. Callus short, blunt. Lodicules 2. Stamens 3. Stigmas 2. Grain small ((1.5-)2.5–3.5(-4) mm long), the hairs apical, minute, stiff, longitudinally grooved. Hilum long-linear (1/2 to 2/3 the length of the grain). Embryo large (1/3 to 1/2 the grain length).
Kranz Anatomy. C3.
2n = 42, 48, 72, and 96, 6, 12, and 16 ploid.
Habitat. Mesophytic.
Classification. Danthonioideae.
Notes. A homogenous genus of New Zealand tussock grasses (with 1 species in Australia), intergrading with Cortaderia and Rytidosperma (Clayton and Renvoize, 1986).
Types Species. C. rigida Zotov.
Biogeographic Element. Clifford & Simon 1981, Simon & Jacobs 1990: Australasian.