Aristida pansa

HABIT Perennial; caespitose. Butt sheaths glabrous, or pubescent. Culms erect; 20–50 cm long; wiry. Leaf-sheaths outer margin hairy. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs. Leaf-blades flat, or involute; 5–15 cm long; 0.7–1.5 mm wide. Leaf-blade surface scabrous; rough adaxially; glabrous, or pubescent; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear, or lanceolate; 10–20 cm long. Primary panicle branches appressed, or ascending; 2–8 cm long. Panicle branches with insignificant pulvini.

Spikelets appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 7–12 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 1 mm long; pubescent; acute.

GLUMES Glumes similar; reaching apex of florets; thinner than fertile lemma. Lower glume lanceolate; 5–7 mm long; 0.6–0.75 length of upper glume; membranous; 1 -veined. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 7–12 mm long; 1 length of adjacent fertile lemma; membranous; 1 -veined. Upper glume lateral veins absent. Upper glume apex acuminate.

FLORETS Fertile lemma linear; subterete; 7–12 mm long; coriaceous; without keel; 3 -veined. Lemma margins convolute; covering most of palea. Lemma apex awned; 3 -awned. Principal lemma awn 3-branched; ascending, or spreading; with 10–20 mm long limb; with a straight or slightly twisted column. Column of lemma awn 2 mm long. Lateral lemma awns spreading as much as principal; 10–20 mm long; subequal to principal.

FLOWER Anthers 3.

DISTRIBUTION North America: southwest USA, south-central USA, and Mexico.

NOTES Aristideae. Gr Tex 1993.

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