Aristida longifolia

HABIT Perennial. Culms 70–130 cm long. Lateral branches lacking. Leaf-sheath oral hairs lacking, or bearded (less frequent, deciduous). Ligule a ciliolate membrane; 0.2 mm long. Collar glabrous. Leaf-blades straight; flat; 35–75 cm long; 3–8 mm wide. Leaf-blade surface scabrous (denselly); rough on both sides; glabrous; hairless throughout. Leaf-blade apex acute; antrorsely scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; 30–60 cm long.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets subterete; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; straight; 1 mm long; bearded; acute.

GLUMES Glumes persistent; dissimilar (lower shorter than upper, rarely subequal or upper slightly longer than lower). Lower glume lanceolate; 8.5–12(–14) mm long; 1 -veined. Lower glume primary vein scabrous. Lower glume surface scabrous; rough generally. Lower glume apex acute; muticous. Upper glume lanceolate; 11–15 mm long; 1 -veined. Upper glume surface smooth. Upper glume apex entire; acute.

FLORETS Fertile lemma subterete; 14.5–16(–18) mm long; without keel; rounded throughout; 3 -veined. Lemma midvein scabrous. Lemma surface smooth; without grooves. Lemma margins convolute. Lemma apex awned; 3 -awned. Principal lemma awn straight; ascending; simple at base; with 20–33 mm long limb; without a column. Lateral lemma awns ascending; 20–33 mm long; subequal to principal.

DISTRIBUTION South America: Mesoamericana, northern South America, western South America, and Brazil.

NOTES Aristideae. LO-W 1993.

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