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.

Lachnagrostis ammobia

HABIT Annual; caespitose. Basal innovations extravaginal. Culms 15–35 cm long. Culm-internodes smooth. Leaf-sheaths striately veined; smooth, or scaberulous. Ligule an eciliate membrane; 2.5–4.5 mm long; scaberulous on abaxial surface; acute. Leaf-blades filiform; involute; 6–16 cm long; 0.4–0.8 mm wide. Leaf-blade surface scaberulous; rough abaxially, or on both sides. Leaf-blade margins scabrous. Leaf-blade apex obtuse.

INFLORESCENCE Inflorescence a panicle; deciduous as a whole. Peduncle fracturing.

Panicle open; elliptic; 10–16 cm long; 1.5–12 cm wide. Panicle branches capillary; scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 5–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 1.5–2 mm long; 0.66 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume elliptic; 1 length of upper glume; membranous; much thinner on margins; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume surface smooth, or asperulous. Lower glume apex acute. Upper glume elliptic; 5–7 mm long; 2 length of adjacent fertile lemma; membranous; with hyaline margins; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume surface smooth, or scabrous. Upper glume apex acute.

FLORETS Fertile lemma oblong; 3.2–3.7 mm long; hyaline; without keel; 5 -veined. Lemma lateral veins excurrent. Lemma surface villous. Lemma apex truncate; awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; straight, or curved; 4–5.5 mm long overall. Palea 0.66–0.75 length of lemma; hyaline; 2 -veined. Rhachilla extension 0.5–0.8 mm long; pilose; with 1–2 mm long hairs.

FLOWER Lodicules 2; 0.9–1.2 mm long; membranous. Anthers 3; 0.9–1.3 mm long.

FRUIT Caryopsis with adherent pericarp; 2 mm long.

DISTRIBUTION Australasia: New Zealand.

NOTES Aveneae. Edgar 1997.

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