Stipa castellanosii

HABIT Perennial; caespitose. Culms erect; 90–100 cm long; 2–3 mm diam. Culm-nodes swollen; brown; glabrous. Lateral branches lacking. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs ciliate; 2 mm long. Ligule a ciliolate membrane; 0.5–1.5 mm long; hyaline. Leaf-blades filiform; flat, or convolute; 12–20 cm long; 1 mm wide; stiff. Leaf-blade surface scaberulous; glabrous. Leaf-blade apex acuminate; muticous.

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

Panicle spiciform; linear; 15–25 cm long; 1.5–2 cm wide. Primary panicle branches appressed; 2–3 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 6.2–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; pubescent; acute.

GLUMES Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 6.2–7 mm long; 1 length of upper glume; hyaline; without keels. Lower glume apex setaceously attenuate. Upper glume lanceolate; 6.2–7 mm long; 2 length of adjacent fertile lemma; hyaline; without keels. Upper glume apex setaceously attenuate.

FLORETS Fertile lemma linear to lanceolate; subterete; 3.8–4 mm long; 0.25 mm wide; scarious; without keel; 5 -veined. Lemma surface scabrous; rough above; pilose; hairy below. Lemma margins convolute; covering most of palea. Lemma apex awned; 1 -awned. Principal lemma awn flexuous; 30–38 mm long overall; deciduous; abscissing from top of lemma. Palea 1 mm long.

FLOWER Anthers 3; yellow.

FRUIT Caryopsis with adherent pericarp; fusiform. Hilum linear.

DISTRIBUTION South America: southern South America.

NOTES Stipeae. Roig 2005.

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