GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Rytidosperma pilosum

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; 25–50 cm long; 3–5 -noded. Culm-nodes glabrous. Leaf-sheaths pilose; with tubercle-based hairs. Ligule a fringe of hairs. Leaf-blades flat, or involute; 6–12 cm long; 1–2 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; lanceolate; 4–5 cm long. Primary panicle branches indistinct the panicle almost racemose, or simple. Panicle branches pubescent.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 7–9 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 9–13 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 0.7–1 mm long; pubescent.

GLUMES Glumes persistent; similar; reaching apex of florets, or exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 9–13 mm long; 1 length of upper glume; membranous; much thinner on margins; 1-keeled; keeled above; 5–7 -veined. Lower glume surface asperulous; rough on veins. Lower glume apex acuminate. Upper glume lanceolate; 9–13 mm long; 1.5 length of adjacent fertile lemma; membranous; with hyaline margins; 1-keeled; keeled above; 5 -veined. Upper glume surface asperulous; rough on veins. Upper glume apex acuminate.

FLORETS Fertile lemma oblong; 6–10 mm long; chartaceous; shiny; without keel; 9 -veined. Lemma surface with a transverse fringe of hair and with marginal hair tufts (above, with or without additional dorsal tufts). Lemma apex lobed; 2 -fid; with lobes 2–4 mm long; incised 0.6 of lemma length; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 11–18 mm long overall; with twisted column. Column of lemma awn 4 mm long. Lateral lemma awns arising on apex of lobes; 6–8 mm long. Palea oblanceolate; 3.5–4 mm long. Palea keels ciliolate. Palea surface pilose; hairy on flanks. Palea apex emarginate. Apical sterile florets resembling fertile though underdeveloped.

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

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Asia-tropical: Malesia. Australasia: Australia and New Zealand. Pacific: north-central.

NOTES Arundineae. Vickery 1993.

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