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.

Melocalamus arrectus

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms scandent; 1000–1500 cm long; 20–40 mm diam.; woody. Culm-internodes terete; hollow; 15–60 cm long; scaberulous; distally glabrous, or pubescent. Culm-nodes swollen; glabrous, or pubescent. Lateral branches dendroid. Bud complement 1. Branch complement one, or two, or three. Culm-sheaths deciduous; 10–14 cm long; 1.6 times as long as wide; coriaceous; pubescent; with appressed hairs; glabrous on margins; truncate at apex; without auricles; ciliate on shoulders. Culm-sheath ligule 1 mm high; ciliate. Culm-sheath blade triangular; erect; 1.6–14 cm long; 17–40 mm wide; pubescent (at base). Leaves 5–8 per branch. Leaf-sheaths 5–12 cm long; keeled; glabrous on surface; outer margin glabrous. Leaf-sheath oral hairs scanty, or lacking; 1–1.5 mm long. Leaf-sheath auricles absent. Ligule an eciliate membrane; 1 mm long; truncate. Leaf-blade base broadly rounded; with a brief petiole-like connection to sheath; petiole 0.2 cm long; petiole glabrous. Leaf-blades lanceolate; 12–22 cm long; 22–40 mm wide. Leaf-blade venation with 12–18 secondary veins; with obscure cross veins. Leaf-blade surface glabrous. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Synflorescence bractiferous; clustered at the nodes; in globose clusters; dense; pubescent on internodes; with glumaceous subtending bracts; with axillary buds at base of spikelet; prophyllate below lateral spikelets; leafless between branches.

Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with diminished florets at the apex. Spikelets obovate; laterally compressed; 2–2.5 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet; shiny. Lower glume ovate; 1.5–2 mm long; chartaceous; without keels. Lower glume apex obtuse. Upper glume ovate; 1.5–2 mm long; chartaceous; without keels. Upper glume apex obtuse.

FLORETS Fertile lemma ovate; 2 mm long; chartaceous; without keel. Lemma apex obtuse. Palea 1 length of lemma. Palea keels ciliolate; adorned below. Palea surface pubescent; hairy on flanks. Apical sterile florets 1 in number; rudimentary.

FLOWER Lodicules 3; 1–1.5 mm long; ciliate. Anthers 6; 1 mm long. Stigmas 2.

FRUIT Caryopsis with fleshy pericarp; orbicular; isodiametric. Endosperm evanescent.

CLEISTOGENES AND VIVIPARY Vivipary occurs.

DISTRIBUTION Asia-temperate: China.

NOTES Bambuseae. Yi 2002.

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