GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Guadua uncinata

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms scandent; 300–800 cm long; 20–60 mm diam.; woody; with root thorns from the nodes. Culm-internodes terete; with small lumen, or solid; 20–40 cm long; distally mealy, or pubescent. Culm-nodes with distinct supra-nodal ridge; pubescent. Lateral branches dendroid; intravaginal. Bud complement 1. Branch complement two, or three, or several; with 1 branch dominant. Culm-sheaths deciduous; 13–28 cm long; 2.8–7.5 length of internode; coriaceous; pubescent; with dark brown hairs; hairy on margins; auriculate; with 4–6 mm high auricles; setose on shoulders; shoulders with straight hairs, or curved hairs; shoulders with 3–7 mm long hairs. Culm-sheath ligule 0.5–1 mm high; ciliate. Culm-sheath blade ovate; demarcated but persistent; erect; 1.7–8.5 cm long; 10–60 mm wide; pubescent; mucronate. Leaves 7–9 per branch. Leaf-sheaths glabrous on surface, or pubescent. Leaf-sheath oral hairs setose; erect, or curly; 6–11 mm long; pale. Leaf-sheath auricles falcate. Ligule an eciliate membrane, or a ciliolate membrane; 0.2–0.8 mm long; pubescent on abaxial surface; truncate. Collar with external ligule. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.3–0.6 cm long; petiole glabrous. Leaf-blades lanceolate, or oblong; 6.5–18 cm long; 14–42 mm wide; dark green and light green; discolorous with last colour beneath. Leaf-blade venation with 15–20 secondary veins; with distinct cross veins. Leaf-blade surface pilose; sparsely hairy; hairy abaxially. Leaf-blade margins scabrous. Leaf-blade apex attenuate.

INFLORESCENCE Synflorescence bractiferous; clustered at the nodes; in untidy tufts; 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 1–2 basal sterile florets; 3–5 fertile florets; with diminished florets at the apex. Spikelets linear, or lanceolate; straight, or curved; subterete; 3–8 mm long; 3–6 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 4–9 mm long; pubescent; hairy at tip.

GLUMES Glumes several; comprising 1–4 gemmiferous bracts; 0 empty glumes; persistent; similar; shorter than spikelet. Upper glume ovate; 3–8 mm long; coriaceous; without keels; 10–15 -veined. Upper glume lateral veins with cross-veins. Upper glume surface glabrous, or puberulous. Upper glume margins eciliate, or ciliolate. Upper glume apex acute; mucronate.

FLORETS Basal sterile florets similar; barren; with palea. Lemma of lower sterile floret ovate; 7–11 mm long; chartaceous; 15–16 -veined; glabrous, or puberulous; smooth on margins; acuminate; mucronate. Palea of lower sterile floret 1 mm long. Fertile lemma ovate; 10–15 mm long; 6–9 mm wide; coriaceous; without keel; 12–25 -veined. Lemma surface glabrous, or puberulous; inner surface pubescent. Lemma apex acuminate; mucronate. Palea 9–14 mm long; 9–13 -veined; 2-keeled. Palea keels winged; conspicuously winged; ciliolate; adorned above; with 0.33 of their length adorned. Apical sterile florets 1 in number; rudimentary.

FLOWER Lodicules 3; 4–6 mm long; membranous; veined; ciliate. Anthers 6; 4–6 mm long; pallid; anther tip apiculate. Stigmas 3. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: western South America.

NOTES Bambuseae. Londonho & Clark 2002.

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