Axonopus argentinus

HABIT Perennial. Rhizomes elongated. Stolons absent, or present. Culms slender; 50–120 cm long; 1–3 -noded. Culm-nodes glabrous. Leaf-sheaths 5–30 cm long; keeled. Ligule a ciliolate membrane; 0.4–0.6 mm long. Leaf-blades 10–30 cm long; 3–5 mm wide. Leaf-blade surface glabrous. Leaf-blade apex abruptly acute, or acute; hooded.

INFLORESCENCE Inflorescence composed of racemes; with 1–2 peduncles per sheath. Peduncle 30–50 cm long.

Racemes 3–10; digitate; ascending; unilateral; 10–18 cm long. Central inflorescence axis 2–4 cm long. Rhachis angular; 0.5–0.7 mm wide; drab; glabrous on surface; scabrous on margins; glabrous on margins. Spikelet packing adaxial; 5.5–7 spikelets per cm.

Spikelets appressed; solitary. Fertile spikelets sessile. Pedicels reduced to a stump; glabrous, or ciliate; hairy at base; with 0.5–1.5 mm long hairs.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; subacute, or acute; 2–2.8 mm long; 0.7–0.8 mm wide; falling entire.

GLUMES Glumes one the lower absent or obscure; reaching apex of florets; thinner than fertile lemma. Upper glume 1 length of spikelet; membranous; 2 -veined. Upper glume primary vein absent. Upper glume surface glabrous, or puberulous; hairy on veins.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; 1 length of fertile lemma; 1 length of spikelet; 2 -veined; without midvein; glabrous, or puberulous; hairy on veins. Fertile lemma 2–2.8 mm long; indurate; dark brown; shiny; without keel. Lemma margins involute. Lemma apex obtuse; without ornament. Palea involute; indurate.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: Brazil and southern South America.

NOTES Paniceae. Black 1994.

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