Stipa atacamensis

HABIT Perennial; caespitose. Culms erect; 15–25 cm long; 0.6–1 mm diam. Culm-internodes distally glabrous, or pubescent. Ligule an eciliate membrane; 2–3 mm long; 0.3–0.5 mm long on basal shoots. Leaf-blades filiform; convolute; 4–8 cm long; 0.5 mm wide. Leaf-blade surface ribbed. Leaf-blade apex pungent.

INFLORESCENCE Inflorescence a panicle; embraced at base by subtending leaf.

Panicle open; linear; 4–6 cm long.

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

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 18 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; curved; 0.75 mm long; glabrous; pungent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 1 length of upper glume; membranous; without keels; 3 -veined. Lower glume apex acuminate. Upper glume lanceolate; 18 mm long; membranous; without keels; 3 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; subterete; 6.5 mm long; coriaceous; without keel; 5 -veined. Lemma surface pubescent; hairy above. Lemma margins convolute; covering most of palea. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn geniculate; 20 mm long overall; with twisted column. Column of lemma awn 10–11 mm long; plumose; with 2–5 mm long hairs. Palea 1 length of lemma; 2 -veined; without keels. Palea surface pubescent.

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

FRUIT Caryopsis with adherent pericarp; fusiform; 5 mm long. Hilum linear.

DISTRIBUTION South America: southern South America.

NOTES Stipeae. Matthei 1995.

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