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.

Rhipidocladum sibilans

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms arching, or leaning; 400–800 cm long; 7–15 mm diam.; woody. Culm-internodes terete; hollow; distally glabrous. Lateral branches dendroid. Branch complement many; flabellate. Culm-sheaths 1.7–2 times as long as wide. Culm-sheath ligule 1–2 mm high; ciliate. Culm-sheath blade triangular; erect; 14–18 cm long; glabrous on surface; acuminate. Leaves 5–7 per branch. Leaf-sheaths glabrous on surface; outer margin glabrous, or hairy. Leaf-sheath oral hairs ciliate; deciduous; 1–3 mm long. Leaf-sheath auricles absent. Ligule an eciliate membrane; 0.2 mm long. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.1 cm long. Leaf-blades 50–70 cm long; 1.8–3.5 mm wide. Leaf-blade midrib indistinct. Leaf-blade surface glabrous, or pubescent; hairy abaxially.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; 4–6 cm long; bearing 2–3 fertile spikelets on each.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with diminished florets at the apex. Spikelets linear; subterete; 15–35 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes elongated between glumes. Rhachilla elongation 8 mm long. Rhachilla internodes 3–4 mm long; pilose; hairy at tip.

GLUMES Glumes several; 4 empty glumes; persistent; shorter than spikelet; thinner than fertile lemma. Lower glume linear; 2–4 mm long; 0.5 length of upper glume. Lower glume apex acute; awned; 1 -awned. Lower glume awn 1–3 mm long. Upper glume lanceolate; 8–9 mm long; chartaceous; without keels; 5–7 -veined. Upper glume surface pubescent; hairy at apex. Upper glume apex acute; awned; 1 -awned. Upper glume awn 3–6 mm long.

FLORETS Fertile lemma lanceolate; 9 mm long; coriaceous; light green and purple; mottled with last colour; without keel; 15–19 -veined. Lemma margins ciliate; hairy above. Lemma apex acute; pubescent; awned; 1 -awned. Principal lemma awn 3–6 mm long overall. Palea 1 length of lemma; 4 -veined. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 3; membranous. Anthers 3; 5 mm long; yellow. Stigmas 2.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: northern South America.

NOTES Bambuseae. Fl Guiana 1995.

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