Orinus alticulmus

HABIT Perennial; caespitose; clumped loosely. Rhizomes elongated; scaly. Culms erect; (28–)40–75 cm long; 1.3–2.2 mm diam.; 5–6 -noded. Culm-nodes pubescent. Leaf-sheaths longer than adjacent culm internode; glabrous on surface. Ligule an eciliate membrane; 1 mm long; lacerate. Leaf-blades flat, or involute; 8–14 cm long; 2–3.5 mm wide. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 4–7; borne along a central axis; unilateral; 1.5 cm long. Central inflorescence axis 5–20 cm long. Spikelet packing broadside to rhachis.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 5–6 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 8–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1 mm long; pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume lanceolate; 4–5 mm long; 0.8 length of upper glume; membranous; much thinner on margins; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface glabrous. Lower glume apex obtuse. Upper glume lanceolate; 4.5–6 mm long; 1 length of adjacent fertile lemma; herbaceous; with membranous margins; 1-keeled; 3 -veined. Upper glume surface glabrous. Upper glume apex obtuse.

FLORETS Fertile lemma lanceolate; 4.5–5.5 mm long; chartaceous; keeled; distinctly keeled; 3 -veined. Lemma midvein pubescent. Lemma surface pubescent; hairy all along; hairy on veins. Lemma apex acute. Palea lanceolate; 1.1 length of lemma. Palea keels pubescent. Palea apex emarginate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 1.5–2.4 mm long; purple.

FRUIT Caryopsis with adherent pericarp; oblong; 2.2–2.6 mm long; light brown.

DISTRIBUTION Asia-temperate: China.

NOTES Eragrostideae. Cai & Zhang 2009.

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