Rytidosperma semiannulare

HABIT Perennial; caespitose. Culms erect; 20–45 cm long; 3 -noded. Culm-nodes glabrous. Leaf-sheaths glabrous on surface. Ligule a fringe of hairs; 0.5 mm long. Leaf-blades straight; involute; 7–15 cm long; 1–2 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; lanceolate; 5–8 cm long. Primary panicle branches appressed. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels scabrous.

FERTILE SPIKELETS Spikelets comprising 5–6 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 7–11 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; pubescent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma; incurved at apex. Lower glume lanceolate; 7–11 mm long; 1 length of upper glume; chartaceous; much thinner on margins; without keels; 7 -veined. Lower glume apex acuminate. Upper glume lanceolate; 7–11 mm long; 1.5 length of adjacent fertile lemma; chartaceous; with membranous margins; without keels; 5 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 4–5 mm long; chartaceous; without keel; 9 -veined. Lemma surface pubescent; with a transverse row of hair tufts. Lemma hairs 3–4 mm long. Lemma apex lobed; 2 -fid; incised 0.5 of lemma length; setaceously attenuate; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 9 mm long overall; with twisted column. Column of lemma awn 2–3 mm long. Palea linear, or oblong; 2.5–3.5 mm long. Palea keels ciliolate; adorned above. Palea surface pubescent; hairy on back; hairy below. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; fleshy; ciliate. Anthers 3; 1 mm long; yellow.

FRUIT Caryopsis with adherent pericarp; obovoid; 1.5 mm long.

DISTRIBUTION Australasia: Australia. Pacific: north-central.

NOTES Arundineae. Vickery 1993.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.