Aristida amazonensis

HABIT Perennial. Culms 35–47 cm long. Lateral branches lacking. Leaf-sheath oral hairs bearded. Ligule a fringe of hairs; 0.1 mm long. Collar glabrous. Leaf-blades straight; conduplicate; 10–14 cm long; 1.8–2 mm wide. Leaf-blade surface scabrous; rough adaxially; pilose; sparsely hairy; hairy adaxially. Leaf-blade apex obtuse; smooth.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted (or subcontracted); 15–29 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; 0.8 mm long; pilose; acute (subacute).

GLUMES Glumes persistent; dissimilar (lower longer than upper sometimes subequal). Lower glume lanceolate; 6.5–8 mm long; 3 -veined. Lower glume primary vein scabrous. Lower glume apex acute (shortly awned); muticous, or mucronate. Upper glume lanceolate; 6.2–7(–7.8) mm long; 1 -veined. Upper glume surface smooth. Upper glume apex entire; acute (shortly awned).

FLORETS Fertile lemma subterete; 8–9 mm long; without keel; rounded throughout; 3 -veined. Lemma surface scaberulous; rough above; without grooves. Lemma margins convolute. Lemma apex awned; 3 -awned. Principal lemma awn straight (or slightly bent); ascending, or spreading; simple at base; with 16.5–20 mm long limb; without a column. Lateral lemma awns ascending; 14.2–18 mm long; shorter than principal (slightly).

DISTRIBUTION South America: Brazil.

NOTES Aristideae. LO-W 1993.

ADDITIONAL CHARACTERS Blades constricted near the apex.

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