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.

Stipa barrancaensis

HABIT Perennial; caespitose. Rhizomes short. Butt sheaths red. Culms erect, or geniculately ascending; 50–60 cm long; 1–1.5 mm diam.; 2–3 -noded. Culm-nodes swollen; brown; glabrous. Leaf-sheaths scaberulous; glabrous on surface, or pubescent; outer margin glabrous, or hairy. Ligule an eciliate membrane; 5 mm long; 1 mm long on basal shoots; acute. Leaf-blades curved; conduplicate; 15–25 cm long; 1 mm wide; stiff. Leaf-blade surface glabrous. Leaf-blade apex acuminate; muticous, or pungent.

INFLORESCENCE Inflorescence a panicle; comprising 10–25 fertile spikelets.

Panicle open; oblong; 15–25 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 7–15 mm long; pubescent.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 37–45 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; curved; 2.5–3 mm long; pungent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 37–45 mm long; 1.1 length of upper glume; membranous; without keels; 3 -veined. Lower glume apex attenuate. Upper glume lanceolate; 32–41 mm long; membranous; without keels; 3 -veined. Upper glume apex attenuate.

FLORETS Fertile lemma lanceolate; subterete; 12–14 mm long; coriaceous; without keel; 5 -veined. Lemma surface pubescent; hairy below. Lemma margins convolute; covering most of palea. Lemma apex awned; 1 -awned. Principal lemma awn geniculate; 130–190 mm long overall; with twisted column. Column of lemma awn 12–23 mm long; plumose; with 10 mm long hairs. Palea 0.5 length of lemma; 0 -veined; without keels.

FLOWER Lodicules 3. Anthers 3; anther tip smooth. Stigmas 2. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; fusiform. Hilum linear.

DISTRIBUTION South America: southern South America.

NOTES Stipeae. Fl Pat 1995.

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