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 volcanicus

HABIT Perennial; caespitose. Culms erect; 30–80 cm long; 1–3 mm diam. Culm-internodes elliptical in section; with small lumen, or solid. Lateral branches ample. Leaf-sheaths longer than adjacent culm internode; keeled; outer margin hairy. Ligule a ciliolate membrane; 0.7–0.9 mm long. Collar pilose. Leaf-blades 9–20 cm long; 4–7 mm wide. Leaf-blade midrib prominent beneath. Leaf-blade margins tuberculate-ciliate. Leaf-blade apex obtuse; hooded.

INFLORESCENCE Inflorescence composed of racemes. Peduncle 6–15 cm long.

Racemes 3–8; digitate; unilateral; 6–13 cm long. Central inflorescence axis 1–3 cm long. Rhachis angular; 0.5 mm wide; with scattered hairs; scabrous on margins; glabrous on margins. Spikelet packing adaxial. Raceme-bases brief; pilose.

Spikelets appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 3–3.5 mm long; falling entire.

GLUMES Glumes one the lower absent or obscure; reaching apex of florets; thinner than fertile lemma. Upper glume ovate; 1 length of spikelet; membranous; without keels; 4–5 -veined. Upper glume primary vein absent, or obscure. Upper glume surface pubescent; hairy at base. Upper glume margins pubescent.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; ovate; 1 length of spikelet; 4–5 -veined; without midvein, or with obscure midvein; pubescent; hairy at base; pubescent on margins. Fertile lemma elliptic; 2.5–3.1 mm long; indurate; without keel. Lemma surface striate. Lemma margins involute. Lemma apex pubescent. Palea involute; indurate.

FLOWER Anthers 3; 2.2 mm long; purple.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: Mesoamericana.

NOTES Paniceae. Fl Costaric 1993.

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