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.

Drake-brockmania somalensis

HABIT Annual; mat forming. Stolons present. Culms prostrate; 5–15 cm long; without nodal roots, or rooting from lower nodes. Ligule an eciliate membrane; 0.7–1 mm long; lacerate; truncate. Leaf-blades 1.5–9.5 cm long; 2.5–4.5 mm wide. Leaf-blade surface hispid; sparsely hairy. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2–6; borne along a central axis; closely spaced; not compacted, or in a head; deflexed, or spreading; oblong to ovate; unilateral; 0.7–1.7 cm long. Central inflorescence axis 0.3–3 cm long. Rhachis deciduous from axis; flattened. Spikelet packing broadside to rhachis; crowded; regular; 2 -rowed.

Spikelets spreading; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 5–9 fertile florets; with diminished florets at the apex. Spikelets oblong, or cuneate; laterally compressed; compressed strongly; 6–11 mm long; falling entire; deciduous with accessory branch structures; readily shedding fertile florets. Rhachilla internodes suppressed between florets.

GLUMES Glumes dissimilar; exceeding apex of florets, or reaching apex of florets, or shorter than spikelet; recurved at apex. Lower glume lanceolate; 2.9–4 mm long; 0.5 length of upper glume; chartaceous; 1-keeled; 1–5 -veined. Lower glume apex acute; mucronate. Upper glume lanceolate; 5–8 mm long; 1.2–1.3 length of adjacent fertile lemma; 1-keeled; 11–17 -veined. Upper glume lateral veins ribbed. Upper glume apex acuminate.

FLORETS Fertile lemma ovate in profile; 4–7 mm long; chartaceous; keeled; 5–7 -veined. Lemma midvein pubescent; hairy below. Lemma margins pubescent; hairy below. Lemma apex acute; muticous, or mucronate. Palea bowed outwards; 2 -veined. Palea keels winged. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; oblong; 0.4–1.2 mm long.

FRUIT Caryopsis with tardily free pericarp; ellipsoid; isodiametric; trigonous; 1.2–1.6 mm long. Embryo 0.4–0.5 length of caryopsis. Hilum punctiform.

DISTRIBUTION Africa: northeast tropical and east tropical. Asia-temperate: Arabia.

NOTES Eragrostideae. WDC.

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