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 mexicanus

HABIT Perennial. Rhizomes elongated. Culms 60 cm long; 1 -noded. Culm-internodes elliptical in section. Culm-nodes glabrous. Leaves mostly basal. Leaf-sheaths 6–10 cm long; longer than adjacent culm internode. Ligule a ciliolate membrane; 0.3 mm long. Leaf-blades 15–25 cm long; 10–15 mm wide. Leaf-blade margins tuberculate-ciliate. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes; with 1 peduncles per sheath. Peduncle 25 cm long.

Racemes 14; digitate; ascending; unilateral; 10–14 cm long. Central inflorescence axis 9 cm long. Rhachis angular; 0.3 mm wide; glabrous on surface; smooth on margins, or scaberulous on margins; glabrous on margins. Spikelet packing adaxial; 5.6 spikelets per cm. Raceme-bases brief; glabrous, or pilose.

Spikelets appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 2–2.1 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 elliptic; 1 length of spikelet; hyaline; pallid; 2–3 -veined. Upper glume primary vein absent, or obscure. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of fertile lemma; 1 length of spikelet; 2–3 -veined; without midvein, or with obscure midvein; acute. Fertile lemma 2–2.1 mm long; indurate; dark brown; shiny; without keel. Lemma margins involute. Lemma apex acute; without ornament. Palea involute; indurate.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION North America: Mexico.

NOTES Paniceae. Black 1994.

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