Mesosetum annuum

HABIT Annual. Culms geniculately ascending, or decumbent; slender; 30–85 cm long; without nodal roots, or rooting from lower nodes. Culm-nodes bearded. Leaves mostly basal. Leaf-sheaths glabrous on surface, or pilose; outer margin hairy. Ligule a fringe of hairs; 0.5 mm long. Leaf-blades 1.2–9.2 cm long; 3–6 mm wide. Leaf-blade surface pilose. Leaf-blade margins glabrous, or ciliate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; unilateral; 2.5–12 cm long. Rhachis angular. Spikelet packing adaxial; regular; 2 -rowed.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 3.5–4 mm long; falling entire. Spikelet callus pubescent.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume lanceolate; asymmetrical; 2.8–3 mm long; 0.75 length of spikelet; chartaceous; 1-keeled; 3 -veined. Lower glume surface pilose; hairy below. Lower glume hairs white. Lower glume apex emarginate, or obtuse. Upper glume lanceolate; 2.3–2.5 mm long; 0.6–1 length of spikelet; membranous; without keels; 3 -veined. Upper glume margins ciliate. Upper glume hairs white. 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; ciliate on midvein; acute. Fertile lemma ovate; dorsally compressed; 2.5–3 mm long; coriaceous; without keel; 5 -veined. Lemma margins flat. Lemma apex acuminate. Palea coriaceous; without keels.

FLOWER Anthers 3; purple.

FRUIT Caryopsis ellipsoid; 2.2 mm long. 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.