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.

Lachnagrostis preissii

HABIT Annual; caespitose. Culms erect, or geniculately ascending; 12–45 cm long. Culm-internodes smooth. Leaf-sheaths smooth; glabrous on surface. Ligule an eciliate membrane. Leaf-blades filiform; conduplicate; 0.5 mm wide. Leaf-blade surface smooth.

INFLORESCENCE Inflorescence a panicle. Peduncle smooth.

Panicle open; linear; 4–15 cm long. Primary panicle branches appressed. Panicle axis scabrous. Panicle branches capillary; scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets elliptic; laterally compressed; 4–4.5 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; shiny; gaping. Lower glume lanceolate; 2.7–5.5 mm long; 1.1 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 apex acuminate. Upper glume lanceolate; 3.6–4.2 mm long; 1.1–1.2 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 apex acuminate.

FLORETS Fertile lemma elliptic; 4 mm long; hyaline; without keel; 5 -veined. Lemma surface pilose. Lemma apex dentate; 4 -fid; with simple equal lobes; truncate; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; geniculate; 8–9 mm long overall; with twisted column. Palea 0.75 length of lemma; hyaline. Rhachilla extension pilose.

FLOWER Lodicules 2; membranous. Anthers 3.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION Australasia: Australia.

NOTES Aveneae. Fl W Austral 1994.

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