GrassBase - The Online World Grass Flora


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

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

Stipa nullanulla

HABIT Perennial; caespitose. Rootstock evident. Culms erect; 40–50 cm long; 1–2 mm diam.; 2 -noded. Culm-internodes distally glabrous, or pubescent. Culm-nodes glabrous. Lateral branches lacking. Leaf-sheaths loose; longer than adjacent culm internode; glabrous on surface; outer margin hairy. Ligule an eciliate membrane; 1–5 mm long; lacerate. Leaf-blades flat, or involute; 15–20 cm long; 2–3 mm wide; stiff. Leaf-blade surface ribbed; scaberulous; rough abaxially; pubescent; hairy adaxially. Leaf-blade margins scabrous. Leaf-blade apex hardened.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 13–19 cm long. Primary panicle branches spreading; 4–6 cm long. Panicle axis scabrous. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 3–15 mm long.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 9–11 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 2–2.7 mm long; pubescent; pungent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 9–11 mm long; 1 length of upper glume; membranous; without keels; 3 -veined. Lower glume apex acute, or acuminate. Upper glume lanceolate; 8–10 mm long; membranous; without keels; 5 -veined. Upper glume apex acute, or acuminate.

FLORETS Fertile lemma linear; subterete; 5–6 mm long; cartilaginous; dark brown; shiny; without keel; 5 -veined. Lemma surface glabrous. Lemma margins flat; covering most of palea. Lemma apex scabrous; with a short cylindrical neck and surmounted by a ring of hairs; with this appendage 1–1.5 mm long (as to hairs); awned; 1 -awned. Principal lemma awn bigeniculate; 50–70 mm long overall; with twisted column. Middle segment of lemma awn 10–15 mm long. Column of lemma awn 50–60 mm long; puberulous; with 0.2 mm long hairs. Palea 1 length of lemma; 2 -veined; without keels. Palea surface glabrous, or pubescent; hairy above.

FLOWER Lodicules 3. Anthers 3; anther tip smooth. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; 2.7–3 mm long. Embryo 0.25–0.33 length of caryopsis. Hilum linear; 0.66–0.75 length of caryopsis.

DISTRIBUTION Australasia: Australia.

NOTES Stipeae. Vickery etc 1994.

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