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.

Eragrostis riparia

HABIT Annual, or perennial; short-lived. Culms erect, or geniculately ascending; 15–40 cm long. Culm-internodes smooth, or scaberulous. Culm-nodes glabrous. Lateral branches ample. Leaf-sheaths striately veined; smooth, or scaberulous; glabrous on surface, or pilose; with tubercle-based hairs; outer margin hairy. Leaf-sheath oral hairs bearded; 3–4 mm long. Ligule a fringe of hairs; 0.3 mm long. Leaf-blades flat, or convolute; 3–7 cm long; 2–5 mm wide; stiff. Leaf-blade surface scaberulous; glabrous; hairless throughout, or except near base. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle. Peduncle smooth.

Panicle spiciform; oblong; 2–7 cm long; 0.25–0.75 cm wide. Primary panicle branches 0.5–2 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 0.5–2.75 mm long.

FERTILE SPIKELETS Spikelets comprising 5–8 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 3–4 mm long; 1–1.75 mm wide; breaking up at maturity; rhachilla deciduous; disarticulating below each fertile floret. Rhachilla internodes 0.3 mm long.

GLUMES Glumes deciduous; similar; shorter than spikelet. Lower glume ovate; 1 mm long; 0.75 length of upper glume; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume apex obtuse, or acute. Upper glume ovate; 1.3–1.5 mm long; 1 length of adjacent fertile lemma; 1-keeled; 1 -veined. Upper glume primary vein scaberulous. Upper glume lateral veins absent. Upper glume apex obtuse, or acute.

FLORETS Fertile lemma ovate; 1.25–1.5 mm long; chartaceous; keeled; 3 -veined. Lemma midvein without distinctive roughness, or scaberulous. Lemma surface smooth, or scaberulous. Lemma apex obtuse. Palea 1–1.3 mm long. Palea keels scaberulous; ciliate; with hairs 0.2 mm long. Apical sterile florets resembling fertile though underdeveloped.

FRUIT Caryopsis with adherent pericarp; ovoid, or orbicular; 0.5 mm long; dark brown. Embryo 0.5 length of caryopsis; projecting below grain.

DISTRIBUTION Asia-tropical: India, Indo-China, and Malesia.

NOTES Eragrostideae. Fl Ceyl 1993.

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