Thamnocalamus unispiculatus

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms erect; 300–500 cm long; 10–15(–20) mm diam.; woody. Culm-internodes terete; solid; (6–)20–25(–30) cm long; mid-green; distally mealy. Culm-nodes swollen. Lateral branches dendroid. Bud complement 1. Branch complement one to several; in a horizontal line. Culm-sheaths deciduous; 0.5 length of internode; coriaceous; pilose; with yellow hairs; hairy on margins; without auricles; ciliate on shoulders; shoulders with straight hairs; shoulders with 4 mm long hairs. Culm-sheath ligule 1 mm high; ciliate. Culm-sheath blade triangular; erect, or reflexed; 0.8–3.3 cm long; 2–4 mm wide; glabrous on surface. Leaves 3–6 per branch. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs scanty; deciduous. Leaf-sheath auricles absent. Ligule a ciliolate membrane; 0.5 mm long; scarious; purple; truncate. Leaf-blade base cuneate; with a brief petiole-like connection to sheath; petiole 0.1–0.15 cm long. Leaf-blades linear, or lanceolate; 2.5–7.2 cm long; 3.5–7 mm wide. Leaf-blade venation with 2–4 secondary veins; with distinct cross veins. Leaf-blade surface glabrous. Leaf-blade margins scabrous.

INFLORESCENCE Synflorescence bractiferous; fasciculate; with spathaceous subtending bracts; bracts 20–27 mm long; without axillary buds at base of spikelet; with ultimate bract subtending a compact bracteolate fascicle of spikelets.

Fertile spikelets pedicelled. Pedicels 1 mm long; glabrous.

FERTILE SPIKELETS Spikelets comprising 5–6 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 25–32 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 2–3 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 8–10 mm long; 0.9 length of upper glume; chartaceous; without keels; 5 -veined. Lower glume apex acuminate. Upper glume lanceolate; 8.5–11 mm long; 0.7–0.8 length of adjacent fertile lemma; chartaceous; without keels; 7 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 10–15 mm long; chartaceous; without keel; (5–)7–9 -veined. Lemma apex attenuate. Palea 5–10 mm long; 8 -veined. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 3; lanceolate; 1.5 mm long; ciliate. Stigmas 3; plumose.

FRUIT Caryopsis with adherent pericarp; linear, or oblong; sulcate on hilar side; 6–7 mm long.

DISTRIBUTION Asia-temperate: China.

NOTES Arundinarieae. Yi & Shi 2011.

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