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.

Deyeuxia pusilla

HABIT Perennial; caespitose. Culms erect; 2–5 cm long; 0.5 mm diam.; 2 -noded. Culm-internodes striate; distally glabrous. Leaf-sheaths longer than adjacent culm internode; striately veined; papillose; glabrous on surface. Ligule an eciliate membrane; 0.5 mm long; entire, or erose; truncate, or obtuse. Leaf-blades straight, or curved; filiform; conduplicate; 1–2.8 cm long; 0.4–0.6 mm wide; stiff. Leaf-blade venation with 4 secondary veins. Leaf-blade surface papillose; glabrous. Leaf-blade apex obtuse; callose.

INFLORESCENCE Inflorescence a panicle; shorter than basal leaves.

Panicle open; oblong; 1.5–1.8 cm long; bearing few spikelets. Primary panicle branches ascending; simple. Panicle axis scabrous. Panicle branches stiff; angular; with prominent pulvini.

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

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets ovate; laterally compressed; 1.8–2 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent. Floret callus hairs 0.2–0.3 mm long; 0.1–0.2 length of lemma.

GLUMES Glumes persistent; similar; shorter than spikelet; firmer than fertile lemma; shiny. Lower glume lanceolate; 1.2–1.3 mm long; 1 length of upper glume; coriaceous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume lanceolate; 1.2–1.5 mm long; 0.75 length of adjacent fertile lemma; coriaceous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 1.8–2 mm long; chartaceous; without keel, or keeled; lightly keeled; 5 -veined. Lemma lateral veins obscure. Lemma apex obtuse; awned; 1 -awned. Principal lemma awn dorsal; arising 0.75 way up back of lemma; straight; 1.3 mm long overall. Palea 1 length of lemma; 2 -veined. Palea keels contiguous above a sulcus. Rhachilla extension 1 mm long; pilose.

FLOWER Lodicules 2; 0.8 mm long. Anthers 3; 0.6 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-tropical: Papuasia.

NOTES Aveneae. Reeder 1997.

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