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.

Deschampsia mendocina

HABIT Perennial; caespitose; clumped loosely. Rhizomes short. Culms erect; 20–25 cm long. Leaves mostly basal. Leaf-sheaths striately veined; smooth; glabrous on surface. Ligule an eciliate membrane; 4–6 mm long; acute. Leaf-blades curved; filiform; conduplicate; 6–8 cm long; 0.5–1 mm wide. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; oblong; 5–7 cm long; 1–1.5 cm wide. Primary panicle branches appressed; 2–3 cm long; bearing spikelets almost to the base. Panicle branches glabrous, or puberulous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels scabrous; glabrous.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with a barren rhachilla extension. Spikelets lanceolate, or oblong; laterally compressed; 3.8–4 mm long; breaking up at maturity; disarticulating above glumes but not between florets. Rhachilla internodes definite; 1 mm long; villous; with 1.5 mm long hairs. Floret callus bearded. Floret callus hairs 1.5 mm long; 0.33 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; similar to fertile lemma in texture; shiny. Lower glume lanceolate; 3.6–3.8 mm long; 0.9 length of upper glume; membranous; much thinner on margins; purple; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 3.8–4 mm long; 1.5 length of adjacent fertile lemma; membranous; with scarious margins; purple; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; 2.5 mm long; membranous; much thinner above; dark brown; shiny; without keel; 5 -veined. Lemma apex dentate; 4 -fid; with simple equal lobes; awned; 1 -awned. Principal lemma awn dorsal; arising 0.1 way up back of lemma; straight; 3 mm long overall. Palea 1 length of lemma. Rhachilla extension 1 mm long; pubescent.

FLOWER Lodicules 2; membranous. Anthers 3; 0.8–1 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION South America: southern South America.

NOTES Aveneae. Parodi 1997.

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