GrassBase - The Online World Grass Flora

Descriptions

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

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

Rytidosperma penicillatum

HABIT Perennial; caespitose; clumped loosely. Culms geniculately ascending, or decumbent; slender; 35–75 cm long; 3–4 -noded. Culm-nodes glabrous. Leaf-sheaths smooth, or scaberulous; glabrous on surface, or hirsute. Ligule a fringe of hairs. Leaf-blades filiform, or linear; flat, or involute; 7–15 cm long; 1–2 mm wide. Leaf-blade surface hirsute; sparsely hairy.

INFLORESCENCE Inflorescence a panicle. Peduncle pubescent above.

Panicle open; linear; nodding; 5–10 cm long. Primary panicle branches indistinct the panicle almost racemose. Panicle axis pubescent.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels pubescent.

FERTILE SPIKELETS Spikelets comprising 4–6 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 10–12 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 1 mm long; pubescent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 10–12 mm long; 1 length of upper glume; membranous; without keels; 9 -veined. Lower glume apex acute, or acuminate. Upper glume lanceolate; 10–12 mm long; 1.3 length of adjacent fertile lemma; membranous; without keels; 5 -veined. Upper glume apex acute, or acuminate.

FLORETS Fertile lemma oblong; 8 mm long; chartaceous; shiny; without keel; 9 -veined. Lemma surface with marginal hair tufts (above and below, with or without dorsal tufts), or with marginal hair tufts and with a transverse row of hair tufts (below). Lemma hairs 1–2 mm long. Lemma apex lobed; 2 -fid; with lanceolate lobes; with lobes 4 mm long; incised 0.5 of lemma length; acuminate; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 11–12 mm long overall; with twisted column. Lateral lemma awns arising on apex of lobes; 3–4 mm long. Palea lanceolate; 4–4.5 mm long. Palea keels ciliolate. Palea apex emarginate, or truncate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; fleshy; ciliate. Anthers 3; 0.75 mm long.

FRUIT Caryopsis with adherent pericarp; oblong; 2–2.5 mm long.

DISTRIBUTION Asia-tropical: Papuasia. Australasia: Australia and New Zealand.

NOTES Arundineae. Vickery 1993.

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