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.

Eragrostis pergracilis

HABIT Annual. Culms erect; slender; 10–30 cm long; 2–3 -noded. Lateral branches lacking. Leaf-sheaths wider than blade at the collar; glabrous on surface. Ligule a fringe of hairs. Leaf-blades filiform; involute; 1–5 cm long; 1–1.5 mm wide. Leaf-blade midrib keeled beneath. Leaf-blade venation with 9–11 secondary veins. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; dense, or loose; 3–12 cm long; 2–6 cm wide; 0.25–0.33 of culm length. Primary panicle branches 5–10 -nate; rebranched near base; 1–2.5 cm long. Panicle axis smooth, or scaberulous. Panicle branches capillary; flexuous; angular; smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 20–50 fertile florets; with diminished florets at the apex. Spikelets linear; curved; laterally compressed, or subterete; compressed slightly; 10–40 mm long; 1–1.2 mm wide; breaking up at maturity; rhachilla persistent; retaining paleas. Rhachilla internodes 0.6–0.7 mm long.

GLUMES Glumes deciduous; similar; shorter than spikelet. Lower glume ovate; 1–1.4 mm long; 0.8–0.9 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume ovate; 1–1.4 mm long; 0.66–0.9 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex obtuse.

FLORETS Fertile lemma elliptic, or ovate; elliptic in profile; 1.5–1.6 mm long; membranous; keeled; 3 -veined. Lemma midvein scaberulous. Lemma apex entire, or erose; emarginate, or obtuse. Palea 1.3–1.4 mm long. Palea keels scaberulous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; oblong; 0.3–0.4 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid, or ovoid; dorsally compressed; 0.45–0.55 mm long; obtuse.

DISTRIBUTION Australasia: Australia.

NOTES Eragrostideae. Blake 1994.

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