Paspalum affine

HABIT Perennial. Culms geniculately ascending, or decumbent; 100–200 cm long; without nodal roots, or rooting from lower nodes. Culm-internodes elliptical in section; distally glabrous. Culm-nodes pubescent. Lateral branches lacking, or sparse. Leaf-sheaths keeled; glabrous on surface, or hispid; with tubercle-based hairs. Ligule an eciliate membrane; 2 mm long. Leaf-blades ascending, or spreading; 15–50 cm long; 12–23 mm wide. Leaf-blade surface glabrous; hairless except near base. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 10–31; borne along a central axis; ascending, or drooping; arcuate; unilateral; 4–11 cm long. Central inflorescence axis 8–18 cm long. Rhachis wingless; angular; 0.5–0.7 mm wide. Spikelet packing crowded. Raceme-bases brief; hirsute.

Spikelets in pairs. Fertile spikelets sessile and pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic, or obovate; dorsally compressed; plano-convex; subacute; 2–2.3 mm long; 1.5 mm wide; falling entire.

GLUMES Glumes one the lower absent or obscure; reaching apex of florets; thinner than fertile lemma. Upper glume elliptic; 1 length of spikelet; membranous; dark green; without keels; 3 -veined. Upper glume surface puberulous. Upper glume margins pubescent. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of spikelet; membranous; dark green; 3 -veined; acute. Fertile lemma elliptic; 2 mm long; indurate; pallid; shiny; without keel. Lemma margins involute. Palea involute; indurate.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION North America: Mexico. South America: Mesoamericana and western South America.

NOTES Paniceae. Chase 1994.

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