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 racemiflorum

HABIT Perennial; caespitose; clumped densely. Rhizomes short; pachymorph. Culms arching, or leaning; 1000–1500 cm long; 5–10 mm diam.; woody. Culm-internodes terete; hollow; distally glabrous. Lateral branches dendroid. Branch complement many; flabellate. Culm-sheath ligule 0.5 mm high. Culm-sheath blade triangular; erect; 3–4 cm long; acuminate. Leaf-sheaths outer margin hairy. Leaf-sheath oral hairs setose; deciduous; 6–8 mm long. Leaf-sheath auricles absent. Ligule an eciliate membrane; 0.2–0.5 mm long. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.1–0.15 cm long; petiole glabrous, or pubescent. Leaf-blades linear, or lanceolate; 6–8 cm long; 5–9 mm wide. Leaf-blade midrib indistinct. Leaf-blade surface glabrous; hairless except near base (where woolly tuft beneath).

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; unilateral; 4–6 cm long; bearing 10 fertile spikelets on each. Spikelet packing 2 -rowed.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with diminished florets at the apex. Spikelets oblanceolate; laterally compressed; 14–18 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes elongated below proximal fertile floret. Rhachilla elongation 1 mm long.

GLUMES Glumes several; 3 empty glumes; persistent; dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume linear; 2.8–3.9 mm long; 3 -veined. Lower glume apex acute. Upper glume ovate; 6–6.5 mm long; chartaceous; without keels; 5–7 -veined. Upper glume apex acute.

FLORETS Fertile lemma ovate; 8–10 mm long; coriaceous; without keel; 5–7 -veined. Lemma margins ciliate; hairy above. Lemma apex acute; awned; 1 -awned. Principal lemma awn 1–2 mm long overall. Palea bowed outwards; 1 length of lemma. Palea keels ciliolate; adorned above. 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 North America: Mexico. South America: Mesoamericana, northern South America, western South America, Brazil, and southern South America.

NOTES Bambuseae. Fl Costa Rica 1995.

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