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.

Melica rigida

HABIT Perennial. Rhizomes short. Culms erect; 20–75 cm long. Culm-internodes smooth. Lateral branches lacking. Leaf-sheaths tubular for much of their length; with 1 of their length closed; retrorsely scabrous; glabrous on surface. Ligule an eciliate membrane; 0.5–5 mm long; pubescent on abaxial surface; lacerate. Leaf-blades flat, or involute; 3–9 cm long; 2–2.5 mm wide; stiff. Leaf-blade surface scabrous; rough adaxially; glabrous, or puberulous. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open, or contracted; linear; 6–20 cm long; 1–2 cm wide. Primary panicle branches appressed; simple. Panicle axis dominant; scaberulous. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; curved; scabrous; pubescent; hairy above.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with diminished florets at the apex. Spikelets elliptic; dorsally compressed; 8–11 mm long; falling entire. Rhachilla internodes scaberulous. Floret callus pubescent. Floret callus hairs 0.1–0.3 mm long.

GLUMES Glumes dissimilar; with lower wider than upper; exceeding apex of florets; thinner than fertile lemma. Lower glume obovate; 8–11 mm long; 1 length of upper glume; membranous; much thinner above; much thinner on margins; without keels; 7–9 -veined. Lower glume apex obtuse. Upper glume lanceolate; 4–6 mm long; 1 length of adjacent fertile lemma; membranous; much thinner above; with hyaline margins; without keels; 5–7 -veined. Upper glume apex acute.

FLORETS Fertile lemma elliptic; 5.5–8.5 mm long; 2–2.5 mm wide; chartaceous; much thinner above; much thinner on margins; without keel. Lemma lateral veins obscure. Lemma surface scaberulous. Lemma margins ciliate. Lemma hairs 0.5 mm long. Lemma apex acute. Palea oblanceolate; 5–6 mm long; 2 -veined. Palea keels ciliolate. Palea surface smooth. Palea apex dentate; 2 -fid. Apical sterile florets barren; in a clump; cuneate; 1.5–3 mm long. Apical sterile lemmas truncate.

FLOWER Lodicules 2; united; oblong; 0.3–0.5 mm long; fleshy; truncate. Anthers 3; 1–1.5 mm long; eventually exserted, or retained within floret.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 2.5–3 mm long; dark brown. Embryo 0.25 length of caryopsis. Hilum linear.

DISTRIBUTION South America: Brazil and southern South America.

NOTES Meliceae. Torres 1995.

Please cite this publication as detailed in How to Cite Version: 27th January 2014.