Chusquea matlatzinca

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms leaning, or scandent; 200–500 cm long; 5–10 mm diam.; woody; 10–30 -noded; rooting from lower nodes. Culm-internodes terete; solid; 12.6–28.5 cm long; mid-green and purple; mottled; distally glabrous. Culm-nodes with distinct supra-nodal ridge. Lateral branches dendroid; extravaginal, or infravaginal; ascending, or spreading. Bud complement 5–10. Branch complement several; in a horizontal line (bulging downwards at centre); with 1 branch dominant. Culm-sheaths deciduous but leaving a persistent girdle; 5.5–11.5 cm long; 1 times as long as wide; yellow, or green; glabrous. Culm-sheath ligule 1–3 mm high. Culm-sheath blade triangular; deciduous; erect; 1–1.3 cm long; glabrous on surface; acuminate. Leaves 3–5 per branch. Leaf-sheaths smooth, or scaberulous. Ligule an eciliate membrane; 1–5 mm long; truncate. Collar with external ligule. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.2–0.3 cm long; petiole pubescent. Leaf-blades lanceolate; 7–17.5 cm long; 11–18 mm wide; mid-green and glaucous; discolorous with last colour beneath. Leaf-blade venation without cross veins. Leaf-blade surface pubescent; hairy abaxially. Leaf-blade margins scaberulous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; interrupted; 7–13 cm long. Primary panicle branches 0.5–2 cm long. Panicle axis puberulous. Panicle branches pubescent.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels angular; 0.5–3.5 mm long; pubescent.

FERTILE SPIKELETS Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 5.5–6.5 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes two; persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.4–0.7 mm long; 0.5 length of upper glume; membranous; without keels. Lower glume surface pubescent. Upper glume ovate; 0.7–1.1 mm long; 0.15–0.25 length of adjacent fertile lemma; without keels. Upper glume surface pubescent. Upper glume apex obtuse; muticous, or mucronate.

FLORETS Basal sterile florets similar; barren; without significant palea; attached to and deciduous with the fertile. Lemma of lower sterile floret ovate; 2.2–3.5 mm long; 0.5 length of fertile lemma; hyaline; 1–3 -veined; pubescent; ciliolate on margins; awned. Awn of lower sterile floret 1.1–1.5 mm long. Lemma of upper sterile floret ovate; 2.3–2.5 mm long; hyaline; pubescent; ciliolate on margins; awned. Awn of upper sterile floret 1.5–1.9 mm long. Fertile lemma lanceolate; 5–6 mm long; coriaceous; mid-green, or purple; without keel; 5 -veined. Lemma surface pubescent. Lemma margins involute; covering most of palea. Lemma apex acuminate; mucronate. Palea tightly convolute around flower; 5–6 mm long; 2 -veined. Palea keels contiguous above a sulcus. Palea surface pubescent; hairy on flanks. Palea apex with excurrent keel veins.

FLOWER Lodicules 3; 1.5–2 mm long; membranous. Ovary glabrous.

DISTRIBUTION North America: Mexico. South America: Mesoamericana.

NOTES Bambuseae. Clark & Ruiz-Sanchez 2014.

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