Stipa chubutensis

HABIT Perennial; caespitose. Butt sheaths dark brown. Culms 15–35 cm long; 2–3 -noded. Culm-nodes swollen. Leaf-sheaths mostly shorter than adjacent culm internode. Leaf-sheath oral hairs ciliate; 1.5 mm long. Ligule a ciliolate membrane. Leaf-blades straight, or curved; deciduous at the ligule; filiform; conduplicate; 8–20 cm long; 1 mm wide. Leaf-blade surface smooth. Leaf-blade apex hardened.

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

Panicle open; oblong; dense; 5–11 cm long; 2–3 cm wide.

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

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 17–24 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; curved; 1.5–2 mm long; pilose; pungent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 17–24 mm long; 1 length of upper glume; membranous; without keels; 3 -veined. Lower glume apex acuminate. Upper glume lanceolate; 17–24 mm long; membranous; without keels; 3 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; subterete; 7–9 mm long; coriaceous; without keel; 5 -veined. Lemma surface pilose. Lemma margins convolute; covering most of palea. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 27–50 mm long overall; with twisted column. Column of lemma awn 9–13 mm long; hirtellous. Palea 5–6 mm long; 0.75 length of lemma; 2 -veined; without keels. Palea surface pilose.

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

FRUIT Caryopsis with adherent pericarp; fusiform; 6 mm long. 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.