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.

Dactyloctenium geminatum

HABIT Perennial; mat forming. Stolons present. Culms geniculately ascending; 35–112 cm long; rooting from lower nodes. Ligule a ciliolate membrane. Leaf-blades 4–25 cm long; 3–6 mm wide; glaucous. Leaf-blade margins glabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes (1–)2(–3); single, or paired, or digitate; ascending; straight, or arcuate; unilateral; 3–7 cm long. Rhachis deciduous from axis; flattened; smooth on margins; terminating in a barren extension; extension bristle-like. Spikelet packing broadside to rhachis; crowded; regular; 2 -rowed.

Spikelets pectinate; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 3–6 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 3–5.3 mm long; breaking up at maturity; disarticulating above glumes but not between florets.

GLUMES Glumes persistent; dissimilar; shorter than spikelet. Lower glume elliptic, or ovate; 1.3–1.8 mm long; 1 length of upper glume; 1-keeled; 1 -veined. Lower glume primary vein smooth. Lower glume lateral veins absent. Lower glume apex acute. Upper glume elliptic, or ovate; 1.3–1.8 mm long; 0.4–0.5 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein smooth. Upper glume lateral veins absent. Upper glume apex truncate; awned; 1 -awned. Upper glume awn subapical; 2–3 mm long.

FLORETS Fertile florets appressed to rhachilla. Fertile lemma lanceolate in profile; 3–3.8 mm long; membranous; keeled; 3 -veined. Lemma midvein without distinctive roughness. Lemma lateral veins obscure. Lemma apex acute; mucronate. Palea 1 length of lemma; 2 -veined. Palea keels wingless; scaberulous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 1.1–1.7 mm long.

FRUIT Caryopsis with free soft pericarp; obovoid; 1 mm long; rugose.

DISTRIBUTION Africa: northeast tropical, east tropical, southern tropical, south, and western Indian ocean.

NOTES Eragrostideae. FTEA.

ADDITIONAL CHARACTERS Glume awn 1.5(-2) length of body.

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