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.

Munroa decumbens

HABIT Annual; mat forming. Stolons present. Culms decumbent; 6–12 cm long. Culm-internodes alternately elongated and bunched. Culm-nodes glabrous, or pubescent. Lateral branches ample. Ligule a fringe of hairs. Leaf-blades 1.5–2.2 cm long; 1.5–2 mm wide; stiff. Leaf-blade margins cartilaginous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence comprising only a few spikelets; comprising 2–3 fertile spikelets; terminal and axillary (in a leafy fascicle); shorter than basal leaves; subtended by an inflated leaf-sheath (2 sheaths); embraced at base by subtending leaf.

Spikelets solitary. Fertile spikelets sessile; heteromorphic (uppermost lacking lower glume).

FERTILE SPIKELETS Spikelets comprising 6–10 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 4.5–5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent.

GLUMES Glumes persistent; dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume linear; 0.5 length of upper glume; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 4–4.5 mm long; 1.2 length of adjacent fertile lemma; membranous; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma cuneate; 3–3.5 mm long; chartaceous; without keel; 3 -veined. Lemma lateral veins excurrent. Lemma surface granulose; with marginal hair tufts and with tufts of hair on midvein; bearing 4 hair tufts in all. Lemma apex lobed; 3 -fid; with outer lobes longer; incised 0.5 of lemma length; awned; 1 -awned. Principal lemma awn apical; 3 mm long overall. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 2; 0.8–1 mm long. Stigmas 2; protogynous.

FRUIT Caryopsis with adherent pericarp; ovoid; laterally compressed; smooth. Embryo 0.5 length of caryopsis; projecting below grain. Endosperm flinty (translucent).

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

NOTES Eragrostideae. Parodi.

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