Aristida contorta

HABIT Annual, or perennial; short-lived; caespitose. Culms erect, or geniculately ascending; zigzag; 12–44 cm long; 2–4 -noded. Culm-internodes antrorsely scabrous; distally glabrous. Lateral branches ample. Leaf-sheaths smooth, or scaberulous; glabrous on surface, or pilose. Leaf-sheath oral hairs ciliate; 3 mm long. Ligule a fringe of hairs; 0.3–0.5 mm long. Leaf-blades flexuous; filiform; involute; 3–10 cm long; 1 mm wide. Leaf-blade surface smooth, or scaberulous; glabrous, or pilose; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic; 9–26 cm long; 4–9 cm wide. Primary panicle branches 2–3 -nate; 1–2.5 cm long. Panicle branches scaberulous, or scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; compressed slightly; 12–30 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 1–2 mm long; pubescent; pungent. Floret callus hairs 0.1–0.3 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 7.4–14.2 mm long; 0.5–0.6 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface asperulous, or scabrous. Lower glume apex acute, or acuminate. Upper glume lanceolate; 12–30 mm long; 2.5–4 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume surface asperulous, or scabrous. Upper glume apex emarginate, or acute, or acuminate; muticous.

FLORETS Fertile lemma lanceolate; laterally compressed; 4.9–7 mm long; coriaceous; pallid, or light brown; without keel; 3 -veined. Lemma surface scabrous; rough above. Lemma margins convolute; covering most of palea. Lemma apex acute; awned; 3 -awned. Principal lemma awn 3-branched; spreading; with 18–95 mm long limb; with twisted column; deciduous; abscissing from top of lemma. Column of lemma awn 7–26 mm long. Lateral lemma awns spreading as much as principal; 16–92 mm long; subequal to principal. Palea 0.2 length of lemma; without keels.

FLOWER Anthers 3; 1.3 mm long.

FRUIT Caryopsis with adherent pericarp; 3–4.5 mm long. Hilum linear; 0.5–0.6 length of caryopsis.

DISTRIBUTION Australasia: Australia.

NOTES Aristideae. Simon 1993.

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