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 pacoensis

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms scandent; 1000 cm long; 18–23 mm diam.; woody. Culm-internodes terete; with small lumen; 80–85 cm long; grey. Culm-nodes pubescent. Lateral branches dendroid. Branch complement several; with 1 branch dominant; as thick as stem. Culm-sheaths 22–30 cm long; 1.5 times as long as wide; hispid; with black hairs; auriculate; with 5–6 mm high auricles; setose on shoulders; shoulders with straight hairs; shoulders with 25 mm long hairs. Culm-sheath blade ovate; narrower than sheath; reflexed; 13–19 cm long; 45–65 mm wide. Leaves 3 per branch. Leaf-sheath oral hairs setose; 25 mm long. Leaf-sheath auricles erect; 2 mm long. Ligule an eciliate membrane; 2 mm long. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.3 cm long. Leaf-blades elliptic; 30–36 cm long; 60–70 mm wide. Leaf-blade venation with 20–24 secondary veins.

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 clusters.

Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with a barren rhachilla extension. Spikelets obovate; laterally compressed; obtuse; 2.5–3 mm long; breaking up at maturity; disarticulating above glumes but not between florets. Rhachilla internodes suppressed between florets.

GLUMES Glumes several; 2–3 empty glumes; persistent; similar; shorter than spikelet. Upper glume oblate; 2 mm long; 1 length of adjacent fertile lemma; chartaceous; without keels; 5 -veined. Upper glume lateral veins prominent. Upper glume surface pubescent. Upper glume margins ciliolate. Upper glume apex obtuse.

FLORETS Fertile lemma oblate; 2–2.5 mm long; chartaceous; much thinner on margins; without keel; 5 -veined. Lemma surface pubescent. Lemma apex obtuse. Palea not rolled; 2–2.5 mm long. Palea surface pubescent; hairy on flanks.

FLOWER Lodicules 3; 1–1.2 mm long; ciliate. Anthers 6. Stigmas 2.

FRUIT Caryopsis with fleshy pericarp; orbicular; isodiametric.

DISTRIBUTION Asia-tropical: Indo-China.

NOTES Bambuseae. Nguyen & Tran 2011.

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