GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Axonopus oiapocensis

HABIT Annual. Culms 50 cm long; 1 -noded. Culm-nodes bearded. Lateral branches lacking. Leaf-sheaths 5–8 cm long; keeled; papillose. Leaf-sheath oral hairs ciliate. Ligule a ciliolate membrane; 0.2–0.3 mm long. Leaf-blades 5–10 cm long; 2–4 mm wide. Leaf-blade apex obtuse.

INFLORESCENCE Inflorescence composed of racemes; with 2–7 peduncles per sheath. Peduncle 10–20 cm long.

Racemes 2; paired; ascending; unilateral; 1–2.5 cm long. Central inflorescence axis 0 cm long. Rhachis angular; 0.2 mm wide; drab; glabrous on surface; smooth on margins; glabrous on margins. Spikelet packing adaxial; 3–4 spikelets per cm.

Spikelets appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or elliptic; dorsally compressed; acuminate; 2.1 mm long; 0.7 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; 4–5 -veined. Upper glume primary vein absent, or obscure. Upper glume lateral veins obscure, or distinct. Upper glume surface pubescent; hairy between veins.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; 1.1 length of fertile lemma; 1 length of spikelet; 4–5 -veined; without midvein, or with obscure midvein; obscurely veined, or distinctly veined; pubescent; hairy on veins. Fertile lemma 1.8–1.9 mm long; indurate; grey; without keel. Lemma margins involute. Lemma apex obtuse; pubescent. Palea involute; indurate.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: northern South America and Brazil.

NOTES Paniceae. Black 1994.

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