Guadua Macrospiculata

HABIT:

• Perennial; caespitose.
• Rhizomes short; pachymorph.
• Culms scandent; pendulous at the tip; 800–1500 cm long; 18–40 mm diam.; woody; with root thorns from the nodes.
• Culm-internodes terete; thick-walled, or solid; 11–32 cm long; distally pubescent.
• Culm-nodes with distinct supra-nodal ridge; pubescent.
• Lateral branches dendroid; intravaginal.
• Bud complement 1.
• Branch complement many; with 1 branch dominant.
• Culm-sheaths deciduous; 6–14.5 cm long; coriaceous; glabrous; hairy on margins; without auricles, or auriculate; with 1–3 mm high auricles; ciliate on shoulders; shoulders with curved hairs; shoulders with 3 mm long hairs.
• Culm-sheath ligule 1–1.5 mm high; ciliate.
• Culm-sheath blade ovate; demarcated but persistent; erect; 2–10 cm long; 25–90 mm wide; pubescent.
• Leaves 5–15 per branch.
• Leaf-sheaths glabrous on surface, or pubescent; outer margin hairy.
• Leaf-sheath oral hairs setose; erect, or curly; 3–10 mm long.
• Leaf-sheath auricles falcate; 0.5–1.25 mm long.
• Ligule a ciliolate membrane; 0.25 mm long.
• Collar with external ligule.
• Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.1–0.15 cm long; petiole pubescent.
• Leaf-blades lanceolate; 2–12 cm long; 8–28 mm wide.
• Leaf-blade midrib conspicuous.
• Leaf-blade venation with 12–14 secondary veins; with distinct cross veins.
• Leaf-blade surface smooth, or scabrous; rough abaxially; glabrous, or pilose; hairy adaxially.
• 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:

• Spikelets comprising 1–2 basal sterile florets; 6–17 fertile florets; with diminished florets at the apex.
• Spikelets linear, or lanceolate; subterete; 30–170 mm long; 3–5 mm wide; breaking up at maturity; disarticulating below each fertile floret.
• Rhachilla internodes 4–9 mm long; glabrous.

 

GLUMES:

• Glumes several; 0 empty glumes; persistent; similar; shorter than spikelet.
• Upper glume ovate; 4–8 mm long; coriaceous; without keels.
• Upper glume lateral veins with cross-veins.
• Upper glume surface glabrous, or puberulous; inner surface pubescent.
• Upper glume margins eciliate.
• Upper glume apex acute; mucronate.

 

FLORETS:

• Basal sterile florets similar; barren; with palea.
• Lemma of lower sterile floret elliptic; 6–14 mm long; chartaceous; 17–20 -veined; pubescent; hairy above; acuminate; mucronate.
• Palea of lower sterile floret 1 mm long.
• Fertile lemma elliptic; 15–24 mm long; 7–10 mm wide; coriaceous; without keel; 18–25 -veined.
• Lemma lateral veins with cross-veins.
• Lemma surface glabrous; inner surface pubescent.
• Lemma apex acuminate; mucronate.
• Palea 10–16 mm long; 11–13 -veined; 2-keeled.
• Palea keels winged; conspicuously winged; ciliolate; adorned above; with 0.5 of their length adorned.
• Palea surface pubescent; hairy on back.
• Apical sterile florets 1 in number; rudimentary.

 

FLOWER:

• Lodicules 3; 4–8 mm long; membranous; veined; ciliate.
• Anthers 6; 6–7 mm long; yellow; anther tip apiculate.
• Stigmas 3.
• Ovary pubescent on apex.

 

FRUIT:

• Caryopsis with adherent pericarp; fusiform; 7 mm long.

 

DISTRIBUTION:

• Brazil

 

Sources:
GrassBase - The Online World Grass Flora
INBAR (International Network for Bamboo and Rattan)