Arthraxon submuticus

HABIT Annual; mat forming. Culms rambling; 15–100 cm long; rooting from lower nodes. Leaf-sheaths glabrous on surface, or hispid. Ligule an eciliate membrane. Leaf-blade base cordate. Leaf-blades lanceolate, or ovate; 1.5–4 cm long; 4–15 mm wide. Leaf-blade margins tuberculate-ciliate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 3–5; digitate; 1–3 cm long. Rhachis fragile at the nodes; angular; glabrous on margins. Rhachis internodes filiform.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; 0.5–1 mm long; glabrous.

STERILE SPIKELETS Companion sterile spikelets represented by barren pedicels.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; 3 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus glabrous; base obtuse; attached transversely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; chartaceous; without keels; 7 -veined. Lower glume surface convex; scabrous; rough on veins. Lower glume apex acute. Upper glume lanceolate; chartaceous; with hyaline margins; 1-keeled; keeled above; 3 -veined. Upper glume primary vein scaberulous. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline; 2 -veined; obtuse. Fertile lemma ovate; hyaline; without keel; 0 -veined. Lemma apex acute; muticous. Palea absent or minute.

FLOWER Anthers 3; 1.5 mm long.

DISTRIBUTION Asia-temperate: China. Asia-tropical: India and Indo-China.

NOTES Andropogoneae. WDC.

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