Aristida portoricensis

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; 30–50 cm long. Lateral branches sparse. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs scanty. Ligule a fringe of hairs. Leaf-blades curved, or flexuous; involute; 5–10 cm long; 0.5–1 mm wide. Leaf-blade surface hirsute; sparsely hairy; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate; 3–8 cm long; contracted about primary branches. Primary panicle branches ascending, or spreading; 2–4 cm long; bearing spikelets almost to the base. Panicle branches stiff.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 12 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 0.75 mm long; pubescent; pungent.

GLUMES Glumes similar; shorter than spikelet; thinner than fertile lemma. Lower glume linear; 7 mm long; 0.7 length of upper glume; membranous; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume surface scabrous. Lower glume apex setaceously attenuate. Upper glume linear; 10 mm long; membranous; 1 -veined. Upper glume primary vein smooth. Upper glume lateral veins absent. Upper glume surface scabrous. Upper glume apex setaceously attenuate.

FLORETS Fertile lemma linear; subterete; 12 mm long; coriaceous; 3 -veined. Lemma margins convolute; covering most of palea. Lemma apex awned; 3 -awned. Principal lemma awn spreading; with 20–30 mm long limb; with a straight or slightly twisted column. Column of lemma awn 2–3 mm long. Lateral lemma awns spreading less than principal; 20–30 mm long; subequal to principal.

FLOWER Anthers 3.

DISTRIBUTION South America: Caribbean.

NOTES Aristideae. N Amer Fl 1994.

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