Paspalum convexum

HABIT Annual; mat forming, or caespitose. Culms decumbent; 10–60 cm long; 1–1.5 mm diam. Culm-internodes distally glabrous. Culm-nodes glabrous. Lateral branches ample. Leaf-sheaths keeled; glabrous on surface, or pilose; with tubercle-based hairs. Ligule an eciliate membrane; 1–2 mm long; brown. Leaf-blade base broadly rounded. Leaf-blades 5–18 cm long; 5–9 mm wide. Leaf-blade midrib prominent beneath. Leaf-blade surface glabrous to pilose; with tubercle-based hairs.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1–5; borne along a central axis; unilateral; 3–5 cm long. Central inflorescence axis 0–3 cm long. Rhachis narrowly winged; 1 mm wide. Spikelet packing 4 -rowed. Raceme-bases brief; pilose.

Spikelets in pairs. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets orbicular; dorsally compressed; 1.8–2.5 mm long; falling entire.

GLUMES Glumes one the lower absent or obscure; reaching apex of florets; thinner than fertile lemma. Upper glume orbicular; 1 length of spikelet; membranous; without keels; 5–7 -veined. Upper glume surface pubescent. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; orbicular; 1 length of spikelet; membranous; 5 -veined; pubescent; obtuse. Fertile lemma orbicular; 1.8–2.3 mm long; indurate; dark brown; shiny; without keel. Lemma surface striate. Lemma margins involute. Palea involute; indurate.

FLOWER Anthers 3; 0.8–1.1 mm long; purple.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION North America: south-central USA and Mexico. South America: Mesoamericana, Caribbean, northern South America, western South America, and Brazil.

NOTES Paniceae. Fl Costaric 1993.

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