GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Aristida pubescens

HABIT Perennial; caespitose. Basal innovations intravaginal. Culms erect; 10–22 cm long; 2 -noded. Culm-internodes elliptical in section; distally pubescent. Lateral branches lacking. Leaf-sheaths pubescent. Leaf-sheath oral hairs bearded; 3.5 mm long. Ligule a fringe of hairs. Collar pubescent. Leaf-blades straight, or curved, or flexuous; flat, or conduplicate; 4–6 cm long; 2–2.5 mm wide. Leaf-blade surface ribbed; grooved adaxially; scaberulous; rough abaxially; puberulous; hairy adaxially. Leaf-blade margins scaberulous. Leaf-blade apex filiform.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; 4–10 cm long. Panicle axis pubescent. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 11–12 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 1 mm long; pubescent; obtuse.

GLUMES Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume linear, or lanceolate; 9–10.5 mm long; 0.75 length of upper glume; membranous; 1 -veined. Lower glume primary vein ciliolate. Lower glume lateral veins absent. Lower glume surface glabrous, or puberulous. Lower glume apex awned; 1 -awned. Lower glume awn 0.8 mm long. Upper glume linear, or lanceolate; 11–12 mm long; 1.2 length of adjacent fertile lemma; membranous; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex dentate; 2 -fid; mucronate, or awned; 1 -awned. Upper glume awn 0.8 mm long.

FLORETS Fertile lemma linear; subterete; 9 mm long; coriaceous; without keel; 3 -veined. Lemma midvein scabrous. Lemma surface scaberulous; rough above. Lemma margins convolute; covering most of palea. Lemma apex awned; 3 -awned. Principal lemma awn with 14 mm long limb. Lateral lemma awns 12 mm long; subequal to principal, or shorter than principal. Palea 1.5 mm long; 0.1–0.2 length of lemma; hyaline; 0 -veined.

FLOWER Lodicules 2; 1.5 mm long. Anthers 3; 2 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: southern South America.

NOTES Aristideae. Caro & Sanchez 1997.

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