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.

Hymenachne grumosa

HABIT Perennial. Rhizomes elongated. Culms erect; 130–200 cm long. Culm-internodes terete; 8–30 cm long; distally glabrous. Culm-nodes purple; glabrous. Lateral branches ample; arising from upper culm. Leaf-sheaths 9–20 cm long; glabrous on surface. Ligule an eciliate membrane; 1.2–2 mm long. Collar dark; glabrous. Leaf-blade base broadly rounded. Leaf-blades lanceolate; 14–44 cm long; 6–30 mm wide. Leaf-blade midrib conspicuous. Leaf-blade surface glabrous. Leaf-blade margins scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 15–45 cm long; 3.5–13 cm wide; contracted about secondary branches. Primary panicle branches ascending. Panicle axis scabrous. Panicle branches scabrous.

Spikelets in pairs. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; obtuse; 2.3–3 mm long; 0.5–1 mm wide; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 1–1.7 mm long; 0.5–0.75 length of spikelet; membranous; without keels; 3 -veined. Lower glume primary vein scabrous. Lower glume lateral veins transversely connected at apex. Lower glume apex acute. Upper glume elliptic; 1.8–2.5 mm long; 0.9 length of spikelet; membranous; without keels; 5 -veined. Upper glume primary vein scaberulous. Upper glume apex acute.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of spikelet; membranous; 5 -veined; acute. Palea of lower sterile floret 1 length of lemma. Fertile lemma elliptic; dorsally compressed; 2–2.6 mm long; 0.5–0.7 mm wide; chartaceous; without keel; 5 -veined. Lemma margins involute. Lemma apex acute; scabrous. Palea embraced by lemma; involute; chartaceous.

FLOWER Anthers 3.

FRUIT Caryopsis obovoid; 1.1–1.3 mm long; light brown. Embryo 0.5 length of caryopsis. Hilum elliptic.

DISTRIBUTION South America: western South America, Brazil, and southern South America.

NOTES Paniceae. Zuloaga 1994.

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