Axonopus iridifolius

HABIT Perennial. Culms erect, or geniculately ascending; 55–100 cm long. Culm-internodes elliptical in section. Culm-nodes pubescent. Leaves basal and cauline. Leaf-sheaths 5–40 cm long; keeled; pilose. Ligule a ciliolate membrane; 1 mm long. Leaf-blades flat, or conduplicate; 6–25 cm long; 2–19 mm wide. Leaf-blade surface scabrous. Leaf-blade apex obtuse; soon splitting, or simple.

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

Racemes 6–20; digitate, or borne along a central axis; ascending; unilateral; 8–18 cm long. Central inflorescence axis 6–15 cm long. Rhachis angular; 0.3 mm wide; dark-coloured (purple); glabrous on surface; scabrous on margins; glabrous on margins. Spikelet packing adaxial; 5.5 spikelets per cm. Raceme-bases brief; pubescent.

Spikelets appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; obtuse; 2.1–3 mm long; 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; purple; 5 -veined. Upper glume surface puberulous; hairy between veins.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; 1.2–1.4 length of fertile lemma; 1 length of spikelet; purple; 4–5 -veined; without midvein, or with obscure midvein; pubescent; hairy between veins. Fertile lemma 1.8–2.1 mm long; indurate; yellow; without keel. Lemma margins involute. Lemma apex pubescent. Palea involute; indurate.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: northern South America and western South America.

NOTES Paniceae. Black 1994.

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