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.

Racemobambos

HABIT Perennial. Rhizomes absent (14), or elongated (5); pachymorph (5/5). Culms erect (2/15), or leaning (7/15), or scandent (9/15); 300–1280–2600 cm long; woody. Culm-internodes terete. Culm-nodes flush with internodes (9/9). Lateral branches dendroid. Branch complement two (1/18), or three (4/18), or several (12/18), or many (8/18); in a clump (4/4); with subequal branches (5/12), or 1 branch dominant (10/12); as thick as stem (1/1). Culm-sheaths deciduous (11/11); without auricles (15/15). Culm-sheath blade linear (1/7), or lanceolate (5/7), or triangular (1/7); as wide as sheath at base (1/1). Ligule an eciliate membrane (15), or a ciliolate membrane (4). Leaf-blade base without a false petiole (1), or with a brief petiole-like connection to sheath (18). Leaf-blades linear (6), or lanceolate (14); stiff (1), or firm (18).

INFLORESCENCE Inflorescence a panicle (7/18), or composed of racemes (11/18); exserted (16/18), or embraced at base by subtending leaf (2/18).

Panicle open (5/5).

Racemes single (11/11); paucilateral (10/10); bearing few fertile spikelets (11/11); bearing 2 fertile spikelets on each (3/10), or 3 fertile spikelets on each (6/10), or 4 fertile spikelets on each (8/10), or 5 fertile spikelets on each (6/10), or 6–8 fertile spikelets on each (2/10).

Spikelets solitary (18/18). Fertile spikelets sessile (2/18), or sessile and pedicelled (2/18), or pedicelled (14/18).

FERTILE SPIKELETS Spikelets comprising 2 fertile florets (1/18), or 3 fertile florets (5/18), or 4 fertile florets (10/18), or 5 fertile florets (13/18), or 6 fertile florets (8/18), or 7 fertile florets (4/18), or 8 fertile florets (3/18); with diminished florets at the apex (18/18). Spikelets linear (3/18), or lanceolate (13/18), or elliptic (2/18), or oblong (2/18); laterally compressed (18/18); 10–28.59–60 mm long; breaking up at maturity (18/18); disarticulating below each fertile floret (18/18). Rhachilla internodes definite (18/18); glabrous (13/18), or pubescent (5/18).

GLUMES Glumes one the lower absent or obscure (1/18), or two (11/18), or several (6/18); persistent (18/18); shorter than spikelet (18/18). Lower glume lanceolate (4/8), or ovate (4/8); 0.25–0.568–0.75 length of upper glume; membranous (5/5); without keels (5/6), or 1-keeled (1/6); 1 -veined (3/4), or 5 -veined (1/4). Lower glume lateral veins absent (3/17), or distinct (14/17). Lower glume surface without pits (17/17); glabrous (15/17), or puberulous (2/17), or pubescent (1/17). Lower glume apex acute (5/6), or acuminate (1/6), or attenuate (1/6). Upper glume ovate (9/9); 0.6–0.802–1.1 length of adjacent fertile lemma; membranous (5/5); without keels (5/5); 5 -veined (1/8), or 7 -veined (5/8), or 9–10 -veined (1/8). Upper glume surface glabrous (16/18), or puberulous (1/18), or pubescent (1/18). Upper glume apex obtuse (1/9), or acute (6/9), or acuminate (2/9); muticous (8/9), or mucronate (1/9).

FLORETS Fertile lemma ovate (18/18); membranous (5/18), or chartaceous (12/18), or coriaceous (1/18); without keel (18/18); wingless (18/18); 5 -veined (1/7), or 7 -veined (4/7), or 8–9 -veined (2/7), or 10–11 -veined (1/7). Lemma surface unwrinkled (18/18); without grooves (18/18); glabrous (13/18), or puberulous (2/18), or pubescent (4/18), or hirsute (1/18). Lemma margins eciliate (11/18), or ciliolate (1/18), or ciliate (2/18), or pubescent (4/18). Lemma apex acute (4/9), or acuminate (4/9), or setaceously attenuate (1/9); muticous (15/18), or mucronate (3/18). Palea 6–6.5–7 length of lemma; 2 -veined (3/9), or 3 -veined (1/9), or 4–6 -veined (2/9), or 7 -veined (1/9), or 8 -veined (3/9), or 9–10 -veined (2/9); 2-keeled but the uppermost without keels (1/18), or 2-keeled (17/18). Palea keels eciliate (10/18), or pubescent (1/18), or ciliolate (6/18), or ciliate (1/18). Palea surface glabrous (11/18), or puberulous (2/18), or pubescent (6/18). Palea apex dentate (1/1). Apical sterile florets resembling fertile though underdeveloped (14/18), or distinct from fertile (4/18); 1 in number (4/4); rudimentary (4/4).

FLOWER Lodicules absent (1/18), or 3 (17/18); glabrous (9/17), or ciliate (8/17). Anthers 6 (18/18). Stigmas 3 (18/18). Ovary unappendaged (1/18), or umbonate (17/18); glabrous (1/18), or with a few apical hairs (1/18), or pubescent on apex (16/18).

FRUIT Caryopsis with adherent pericarp (18/18).

DISTRIBUTION Tropical Asia.

Please cite this publication as detailed in How to Cite Version: 27th January 2014.