Chusquea arachniformis

HABIT Perennial. Culms scandent; pendulous at the tip; 200–300 cm long; 3–5 mm diam.; woody; without nodal roots. Culm-internodes terete; 20–28 cm long; distally glabrous. Culm-nodes with distinct supra-nodal ridge. Lateral branches dendroid; infravaginal. Branch complement many; in a clump; thinner than stem. Culm-sheaths persistent; 9–26.5 cm long; retrorsely scabrous; pubescent; hairy above; hairy on margins. Culm-sheath ligule 0.5 mm high. Culm-sheath blade lanceolate; indistinctly demarcated from sheath; erect; 0.3–28 cm long; pubescent. Leaves 3–6 per branch. Leaf-sheaths keeled (above); striately veined; glabrous on surface; outer margin hairy. Ligule an eciliate membrane; 1.5–3.5 mm long. Collar with external ligule. Leaf-blade base asymmetrical; with a brief petiole-like connection to sheath; petiole 0.3–0.4 cm long. Leaf-blades lanceolate, or ovate; 9–14 cm long; 16–25 mm wide. Leaf-blade venation without cross veins. Leaf-blade surface glabrous. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle; bracteate at branch bases (1.5–2mm); subtended by an inflated leaf-sheath.

Panicle capitate; linear; continuous, or interrupted; 2–4 cm long; 1.5 cm wide. Panicle axis angular; pubescent. Panicle branches angular; pubescent.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 10.5–11.5 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 3.5–4 mm long; membranous; 1-keeled; 3 -veined. Lower glume surface puberulous. Lower glume apex acuminate; awned; 1 -awned. Lower glume awn 8.5–16 mm long. Upper glume lanceolate; 4–4.5 mm long; 0.33 length of adjacent fertile lemma; membranous; 1-keeled; 5 -veined. Upper glume surface puberulous. Upper glume apex obtuse; awned; 1 -awned. Upper glume awn 2.4–4 mm long.

FLORETS Basal sterile florets barren; without significant palea; attached to and deciduous with the fertile. Lemma of lower sterile floret lanceolate; 9–11.7 mm long; 0.9 length of fertile lemma; chartaceous; 9 -veined; puberulous; hairy above; acute; awned. Awn of lower sterile floret 2.4–4 mm long. Lemma of upper sterile floret lanceolate; 10.9–13 mm long; chartaceous; pubescent; obtuse. Fertile lemma ovate; 9.8–10.7 mm long; coriaceous; without keel; rounded except near apex; 7 -veined. Lemma surface pilose; hairy above. Lemma apex acute. Palea 8.6–9.8 mm long; 4 -veined.

FLOWER Lodicules 3; 1.5–2.5 mm long; membranous; ciliate. Anthers 3; 6 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; apex unappendaged.

DISTRIBUTION South America: western South America.

NOTES Bambuseae. Londono 2001.

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