Stipa macrotricha

HABIT Perennial; caespitose. Butt sheaths thickened and forming a bulb. Culms erect; 60–90 cm long; 2–3 mm diam. Culm-internodes distally glabrous. Leaf-sheath oral hairs ciliate. Ligule an eciliate membrane, or a ciliolate membrane; 6 mm long; lacerate. Collar glabrous. Leaf-blades erect; filiform; involute; 12–27 cm long; 1–1.5 mm wide. Leaf-blade surface glabrous. Leaf-blade apex attenuate; muticous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 12–20 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 11–20 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; curved; 1.8–2 mm long; pungent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume linear; 15–20 mm long; 1 length of upper glume; hyaline; without keels. Lower glume apex setaceously attenuate. Upper glume linear; 15–20 mm long; 2.5 length of adjacent fertile lemma; hyaline; without keels. Upper glume apex attenuate.

FLORETS Fertile lemma linear; subterete; 6–7.5 mm long; chartaceous; without keel. Lemma midvein ciliate; hairy below. Lemma surface papillose; glabrous. Lemma margins convolute; covering most of palea. Lemma apex awned; 1 -awned. Principal lemma awn bigeniculate; 55–80 mm long overall; with 37–54 mm long limb; with twisted column. Column of lemma awn 8–10 mm long; pubescent; with 0.5 mm long hairs.

DISTRIBUTION South America: southern South America.

NOTES Stipeae. Fl San Juan 2011.

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