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.

Stipa arabica

HABIT Perennial; caespitose. Culms erect; 30–70 cm long. Culm-internodes distally pubescent. Leaf-sheaths glabrous on surface, or pubescent. Ligule an eciliate membrane; 4–6 mm long. Leaf-blades filiform; involute; 1–2.5 mm wide; stiff. Leaf-blade surface pubescent; hairy abaxially, or on both sides. Leaf-blade apex hardened.

INFLORESCENCE Inflorescence a panicle; embraced at base by subtending leaf.

Panicle open; linear; 15–35 cm long; bearing few spikelets.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 25–35 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; curved; pubescent; pungent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 1 length of upper glume; membranous; without keels; 3(–5) -veined. Lower glume apex acuminate. Upper glume lanceolate; 25–35 mm long; membranous; without keels; 3(–5) -veined. Upper glume apex acuminate.

FLORETS Fertile lemma elliptic; subterete; 8–11.5 mm long; coriaceous; without keel. Lemma surface pubescent; hairy in lines. Lemma margins convolute; covering most of palea. Lemma apex surmounted by a ring of hairs; awned; 1 -awned. Principal lemma awn bigeniculate; 100–160 mm long overall; with twisted column; deciduous; limb plumose; with 2–4 mm long hairs. Column of lemma awn hirtellous; with 0.5–1.3 mm long hairs. Palea 1 length of lemma; 2 -veined; without keels.

FLOWER Lodicules 3. Anthers 3; anther tip smooth. Stigmas 3. Styles free to the base. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION Europe: eastern. Asia-temperate: Soviet Middle Asia, Caucasus, western Asia, and China. Asia-tropical: India.

NOTES Stipeae. Fl Pak 1993.

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