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 popinense

HABIT Perennial; caespitose. Butt sheaths pallid; glossy; distinctly ribbed. Culms 20–45 cm long. Culm-internodes ridged; smooth. Culm-nodes purple. Leaf-sheaths mostly shorter than adjacent culm internode; ribbed. Ligule a fringe of hairs. Leaf-blades flat, or involute; 7–15 cm long; 1–2 mm wide. Leaf-blade surface ribbed; grooved adaxially and abaxially; scaberulous; rough adaxially. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence a panicle. Peduncle scaberulous above.

Panicle open; linear, or lanceolate; 4–8 cm long. 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; 13–14 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 1–1.5 mm long; bearded.

GLUMES Glumes persistent; similar; reaching apex of florets; thinner than fertile lemma. Lower glume lanceolate; 14 mm long; 1 length of upper glume; membranous; much thinner on margins; without keels; 7 -veined. Lower glume apex acute. Upper glume lanceolate; 13 mm long; membranous; with hyaline margins; without keels; 5 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; 7.5–8 mm long; chartaceous; without keel; 7 -veined. Lemma surface pilose; hairy below; with 2 transverse rows of hair tufts. Lemma hairs 4 mm long. Lemma apex lobed; 2 -fid; with lobes 3.5 mm long; incised 0.33 of lemma length; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 12 mm long overall; with twisted column. Column of lemma awn 2.5 mm long. Lateral lemma awns 3.5 mm long. Palea oblanceolate; 6.5–7 mm long. Palea keels ciliate; adorned all along. Palea surface pilose; hairy on margins; hairy below. Palea apex dentate; 2 -fid. Apical sterile florets resembling fertile though underdeveloped.

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

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

DISTRIBUTION Australasia: Australia.

NOTES Arundineae. Morris 1997.

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