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 pictum

HABIT Perennial; caespitose. Culms 15–35 cm long. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs; 1–1.5 mm long. Leaf-blades flat, or conduplicate, or convolute; 4–12 cm long; 2–3 mm wide; coriaceous. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence a panicle; comprising 20–25 fertile spikelets; embraced at base by subtending leaf.

Panicle contracted; oblong; 3.5–8 cm long. Primary panicle branches 2–3 cm long. Panicle branches glabrous in axils.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels scabrous.

FERTILE SPIKELETS Spikelets comprising 3–4 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 13–16 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; pilose. Floret callus hairs 0.5–1 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma; gaping. Lower glume lanceolate; 11–13 mm long; 1 length of upper glume; membranous; without keels; 3 -veined. Lower glume apex acute. Upper glume lanceolate; 11–13 mm long; 1.3 length of adjacent fertile lemma; membranous; without keels; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; 8.5–12 mm long; chartaceous; without keel; 9 -veined. Lemma surface pilose; hairy below; with a transverse row of hair tufts. Lemma apex lobed; 2 -fid; incised 0.5 of lemma length; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 8.5–11 mm long overall; with twisted column. Lateral lemma awns arising on apex of lobes; 3–4 mm long. Palea 4–5 mm long. Palea keels ciliolate. Palea surface pilose; hairy on back; hairy below. Palea apex emarginate. Apical sterile florets resembling fertile though underdeveloped.

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

FRUIT Caryopsis with adherent pericarp. Embryo 0.5 length of caryopsis.

DISTRIBUTION South America: southern South America.

NOTES Arundineae. Fl Pat 1993.

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