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.

Mesosetum arenarium

HABIT Perennial; caespitose. Rhizomes elongated. Culms erect; 90–120 cm long. Culm-nodes pubescent. Leaf-sheaths glabrous on surface, or hirsute; outer margin glabrous, or hairy. Ligule a fringe of hairs; 3 mm long. Leaf-blades 3–16 cm long; 3–7 mm wide. Leaf-blade surface glabrous, or pilose; hairy on both sides. Leaf-blade margins cartilaginous; glabrous, or ciliate. Leaf-blade apex acuminate; hardened.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; unilateral; 5–14 cm long. Rhachis angular; 1 mm wide; pubescent on surface; ciliate on margins. Spikelet packing adaxial.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 4.4–6.2 mm long; falling entire. Spikelet callus pubescent.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume lanceolate; asymmetrical; 4–5 mm long; 0.8–0.9 length of spikelet; chartaceous; 1-keeled; 3 -veined. Lower glume primary vein ciliate (below). Lower glume lateral veins transversely connected at apex. Lower glume apex acute. Upper glume lanceolate; 4–4.5 mm long; 0.8 length of spikelet; membranous; without keels; 3–5 -veined. Upper glume lateral veins transversely connected at apex. Upper glume margins ciliate. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 1 length of spikelet; membranous; thicker on margins; 5 -veined; pilose; hairy on veins; with dorsal tufts of hair; 1 hair tufts in all; acute. Fertile lemma ovate; dorsally compressed; 3.5–3.8 mm long; coriaceous; without keel; 5 -veined. Lemma margins flat. Lemma apex acuminate. Palea coriaceous; without keels.

FLOWER Anthers 3; 3 mm long; purple.

FRUIT Caryopsis 2.5 mm long; dark brown. Embryo 0.33 length of caryopsis. Hilum linear; 1 length of caryopsis.

DISTRIBUTION South America: Brazil.

NOTES Paniceae. Filgueiras.

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