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.

Nassella laevissima

HABIT Perennial; caespitose; clumped densely. Culms erect; slender; 10–40 cm long; 0.25 mm diam. Lateral branches lacking. Leaves mostly basal. Ligule an eciliate membrane; 1–2 mm long. Leaf-blades filiform; conduplicate; 10–20 cm long; 0.5 mm wide. Leaf-blade surface scabrous; rough adaxially. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle; comprising 3–12 fertile spikelets.

Panicle contracted; linear; 3–10 cm long; bearing few spikelets.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 1.5–10 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 7–8 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; curved; bearded; acute. Floret callus hairs 0.7–1 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 7–8 mm long; 1–1.2 length of upper glume; membranous; purple; 1-keeled; 3 -veined. Lower glume surface pubescent. Lower glume apex attenuate; awned; 1 -awned. Lower glume awn 1.5–2 mm long. Upper glume lanceolate; 1.5–2 mm long; 2–2.2 length of adjacent fertile lemma; membranous; purple; 1-keeled; 3 -veined. Upper glume surface pubescent. Upper glume apex attenuate; awned; 1 -awned. Upper glume awn 1.5–2 mm long.

FLORETS Fertile lemma obovate; laterally compressed; 2.5–3 mm long; coriaceous; shiny; keeled; lightly keeled. Lemma surface glabrous. Lemma margins convolute; covering most of palea. Lemma apex truncate; awned; 1 -awned. Principal lemma awn eccentric; flexuous; 16–22 mm long overall; deciduous. Palea 1.5 mm long; membranous; 0 -veined; without keels.

FLOWER Lodicules 2. Anthers 3.

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

DISTRIBUTION South America: southern South America.

NOTES Stipeae. Fl Pat.

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