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.

Stipa arenicola

HABIT Perennial; caespitose. Butt sheaths purple. Culms erect; 15–25 cm long; 1–1.5 mm diam.; 5–8 -noded. Culm-internodes 10–25 cm long; smooth. Lateral branches ample. Leaf-sheaths striately veined; glabrous on surface; outer margin hairy. Ligule an eciliate membrane; 7–12 mm long; 2–3 mm long on basal shoots; hyaline. Collar pubescent. Leaf-blades filiform; conduplicate; 15–29 cm long; 0.5–1 mm wide. Leaf-blade surface smooth; glabrous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle; comprising 11–12 fertile spikelets; shorter than basal leaves; embraced at base by subtending leaf.

Panicle open; lanceolate to elliptic; 9–14 cm long; bearing few spikelets.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels angular; ciliate; hairy at tip.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 25–31 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; curved; 2.8–3 mm long; pubescent; acute.

GLUMES Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 25–31 mm long; 1.1–1.2 length of upper glume; hyaline; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex attenuate. Upper glume lanceolate; 22–27 mm long; 2 length of adjacent fertile lemma; hyaline; without keels. Upper glume apex attenuate.

FLORETS Fertile lemma lanceolate; subterete; 11–13 mm long; coriaceous; without keel; 5 -veined. Lemma surface pubescent. Lemma margins convolute; covering most of palea. Lemma apex surmounted by a ring of hairs; awned; 1 -awned. Principal lemma awn geniculate; 70–80 mm long overall; with 54–62 mm long limb; with twisted column. Column of lemma awn 16–20 mm long; plumose. Palea tightly convolute around flower; 9.5–10 mm long; 2 -veined; 2-keeled. Palea keels ciliolate.

FLOWER Lodicules 2; 3.5–4 mm long. Stigmas 2. Styles free to the base.

FRUIT Caryopsis with adherent pericarp; fusiform; 9–10 mm long. Hilum linear.

DISTRIBUTION South America: southern South America.

NOTES Stipeae. Roig 2004.

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