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.

Gigantochloa

HABIT Perennial. Rhizomes short; pachymorph. Culms erect (51/51); 300–1254–2600 cm long; woody; without nodal roots (1/5), or rooting from lower nodes (1/5), or with aerial roots from the nodes (4/5). Culm-internodes terete. Culm-nodes swollen (1/1). Lateral branches dendroid. Branch complement one (3/21), or two (1/21), or three (2/21), or several (16/21), or many (2/21); in a horizontal line (1/1); with subequal branches (1/8), or 1 branch dominant (7/8); thinner than stem (1/1). Culm-sheaths persistent (8/30), or tardily deciduous (2/30), or deciduous but leaving a persistent girdle (2/30), or deciduous (18/30); without auricles (2/44), or auriculate (42/44). Culm-sheath blade lanceolate (24/46), or narrowly ovate (3/46), or ovate (9/46), or triangular (11/46); constricted at base (4/20), or narrower than sheath (14/20), or as wide as sheath at base (2/20). Leaf-sheath auricles absent (27), or erect (15), or falcate (14). Ligule an eciliate membrane (45), or a ciliolate membrane (8), or a ciliate membrane (3). Leaf-blade base with a brief petiole-like connection to sheath. Leaf-blades lanceolate (48), or oblong (11), or ovate (2); herbaceous (48), or chartaceous (8). Leaf-blade midrib evident (1/2), or conspicuous (1/2). Leaf-blade venation without cross veins (53), or with obscure cross veins (1), or with distinct cross veins (3).

INFLORESCENCE Synflorescence bractiferous (47/47); clustered at the nodes (47/47); in globose clusters (6/47), or stellate clusters (29/47), or compact unilateral clumps (2/47), or untidy tufts (12/47); with glumaceous subtending bracts (44/47), or spathaceous subtending bracts (3/47); with axillary buds at base of spikelet (47/47); leafy between clusters (1/31), or leafless between clusters (30/31), or leafless between branches (1/31).

Fertile spikelets sessile (47/47).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets (4/4); 1 fertile florets (5/47), or 2 fertile florets (14/47), or 3–4 fertile florets (23/47), or 5 fertile florets (4/47); without rhachilla extension (6/47), or with diminished florets at the apex (41/47). Spikelets linear (5/47), or lanceolate (34/47), or oblong (3/47), or ovate (9/47); laterally compressed (43/47), or subterete (4/47); 6–15.72–50 mm long; breaking up at maturity (47/47); disarticulating above glumes but not between florets (47/47). Rhachilla internodes suppressed between florets (42/43), or definite (1/43). Floret callus pubescent (2/3), or pilose (1/3).

GLUMES Glumes one the lower absent or obscure (2/47), or two (20/47), or several (34/47); persistent (47/47); shorter than spikelet (47/47). Lower glume ovate (13/13). Lower glume surface without pits (46/46); glabrous (45/46), or puberulous (1/46), or pubescent (1/46). Lower glume apex obtuse (1/11), or acute (3/11), or acuminate (7/11); muticous (7/13), or mucronate (6/13). Upper glume lanceolate (2/41), or ovate (39/41), or orbicular (1/41). Upper glume lateral veins with cross-veins (1/1). Upper glume surface glabrous (43/47), or puberulous (1/47), or pubescent (2/47), or pilose (1/47), or hispid (1/47). Upper glume apex obtuse (3/36), or acute (21/36), or acuminate (11/36), or cuspidate (1/36); muticous (22/41), or mucronate (19/41).

FLORETS Basal sterile florets male (4/4); with palea (4/4). Lemma of lower sterile floret lanceolate (1/3), or elliptic (1/3), or obovate (1/3); obtuse (1/2), or acuminate (1/2); muticous (1/3), or mucronate (2/3). Fertile lemma lanceolate (7/47), or elliptic (1/47), or oblong (1/47), or ovate (40/47), or orbicular (1/47); chartaceous (44/47), or coriaceous (3/47); without keel (47/47); wingless (47/47); 8–10 -veined (1/6), or 15–17 -veined (2/6), or 18 -veined (1/6), or 19 -veined (2/6), or 20 -veined (1/6), or 21–27 -veined (2/6), or 28–31 -veined (1/6), or 36–40 -veined (1/6). Lemma surface unwrinkled (47/47); without grooves (47/47); glabrous (35/47), or puberulous (5/47), or pubescent (6/47), or pilose (1/47). Lemma margins flat (46/47), or convolute (1/47); eciliate (18/47), or ciliolate (9/47), or ciliate (20/47), or pilose (1/47). Lemma apex obtuse (2/47), or acute (23/47), or acuminate (17/47), or cuspidate (3/47), or apiculate (1/47), or rostrate (1/47); muticous (37/47), or mucronate (10/47). Palea 0.9–0.9889–1 length of lemma; 3–9–13 -veined; without keels (4/47), or 2-keeled but the uppermost without keels (4/47), or 2-keeled (39/47). Palea keels eciliate (11/43), or puberulous (1/43), or ciliolate (16/43), or ciliate (15/43). Palea surface glabrous (41/47), or puberulous (3/47), or pubescent (1/47), or pilose (2/47). Palea apex entire (3/17), or dentate (14/17). Apical sterile florets 1 in number (34/34); barren (34/34); rudimentary (1/31), or lanceolate (30/31).

FLOWER Lodicules absent (42/47), or 3 (5/47); glabrous (1/5), or ciliate (4/5). Anthers 6 (47/47), or 7 (1/47). Stigmas 1 (38/39), or 2 (3/39); plumose (32/47), or pubescent (15/47). Ovary unappendaged (17/47), or umbonate (30/47); pubescent on apex (25/29), or pubescent all over (4/29).

FRUIT Caryopsis with adherent pericarp (44/44); linear (2/6), or lanceolate (2/6), or oblong (2/6).

DISTRIBUTION Temperate Asia (6), or Tropical Asia (54).

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