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 nudiflorum

HABIT Perennial; caespitose. Rhizomes absent, or short. Butt sheaths persistent and investing base of culm. Culms erect; 10–30 cm long; 2 -noded. Culm-nodes glabrous. Leaf-sheaths glabrous on surface. Ligule a fringe of hairs. Leaf-blades aciculate; involute; 2–10 cm long; 1 mm wide; stiff. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence a panicle; comprising 5–10 fertile spikelets. Peduncle pubescent above.

Panicle contracted; linear, or lanceolate; 3–7 cm long; bearing few spikelets. Panicle axis pubescent. Panicle branches pubescent.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 5–6 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 8–13 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; pilose.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 8–13 mm long; 1 length of upper glume; membranous; without keels; 5 -veined. Lower glume apex acute. Upper glume lanceolate; 8–13 mm long; 1.5–2.3 length of adjacent fertile lemma; membranous; without keels; 5 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; 5.5 mm long; chartaceous; pallid; shiny; without keel; 9 -veined. Lemma surface with marginal hair tufts (rarely with 2 additional dorsal tufts); bearing 4 hair tufts in all, or 6 hair tufts in all. Lemma apex lobed; 2 -fid; with lobes 2.5 mm long; incised 0.33 of lemma length; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 8 mm long overall; with twisted column. Lateral lemma awns arising on apex of lobes; 2.5 mm long. Palea oblong; 4 mm long. Palea keels ciliolate. Palea apex emarginate, or truncate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; fleshy; ciliate. Anthers 3; 1–1.25 mm long; yellow.

FRUIT Caryopsis with adherent pericarp; oblanceolate; 2 mm long.

DISTRIBUTION Australasia: Australia.

NOTES Arundineae. Vickery 1993.

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