Gigantochloa

HABIT Perennial. Rhizomes short; pachymorph. Culms erect (50/50); 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 (3/20), or two (1/20), or three (2/20), or several (15/20), or many (2/20); 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 (24/45), or narrowly ovate (3/45), or ovate (8/45), or triangular (11/45); constricted at base (4/20), or narrower than sheath (14/20), or as wide as sheath at base (2/20). Leaf-sheath auricles absent (26), or erect (15), or falcate (14). Ligule an eciliate membrane (44), or a ciliolate membrane (8), or a ciliate membrane (3). Leaf-blade base with a brief petiole-like connection to sheath. Leaf-blades lanceolate (47), or oblong (11), or ovate (2); herbaceous (47), or chartaceous (8). Leaf-blade midrib evident (1/2), or conspicuous (1/2). Leaf-blade venation without cross veins (52), or with obscure cross veins (1), or with distinct cross veins (3).

INFLORESCENCE Synflorescence bractiferous (46/46); clustered at the nodes (46/46); in globose clusters (6/46), or stellate clusters (28/46), or compact unilateral clumps (2/46), or untidy tufts (12/46); with glumaceous subtending bracts (43/46), or spathaceous subtending bracts (3/46); with axillary buds at base of spikelet (46/46); leafy between clusters (1/30), or leafless between clusters (29/30), or leafless between branches (1/30).

Fertile spikelets sessile (46/46).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets (4/4); 1 fertile florets (5/46), or 2 fertile florets (13/46), or 3–4 fertile florets (23/46), or 5 fertile florets (4/46); without rhachilla extension (6/46), or with diminished florets at the apex (40/46). Spikelets linear (5/46), or lanceolate (33/46), or oblong (3/46), or ovate (9/46); laterally compressed (42/46), or subterete (4/46); 6–15.68–50 mm long; breaking up at maturity (46/46); disarticulating above glumes but not between florets (46/46). Rhachilla internodes suppressed between florets (41/42), or definite (1/42). Floret callus pubescent (2/3), or pilose (1/3).

GLUMES Glumes one the lower absent or obscure (2/46), or two (20/46), or several (33/46); persistent (46/46); shorter than spikelet (46/46). Lower glume ovate (13/13). Lower glume surface without pits (45/45); glabrous (44/45), or puberulous (1/45), or pubescent (1/45). Lower glume apex obtuse (1/11), or acute (3/11), or acuminate (7/11); muticous (7/13), or mucronate (6/13). Upper glume lanceolate (2/40), or ovate (38/40), or orbicular (1/40). Upper glume lateral veins with cross-veins (1/1). Upper glume surface glabrous (42/46), or puberulous (1/46), or pubescent (2/46), or pilose (1/46), or hispid (1/46). Upper glume apex obtuse (3/36), or acute (21/36), or acuminate (11/36), or cuspidate (1/36); muticous (22/40), or mucronate (18/40).

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 (7/46), or elliptic (1/46), or oblong (1/46), or ovate (39/46), or orbicular (1/46); chartaceous (43/46), or coriaceous (3/46); without keel (46/46); wingless (46/46); 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 (46/46); without grooves (46/46); glabrous (34/46), or puberulous (5/46), or pubescent (6/46), or pilose (1/46). Lemma margins flat (45/46), or convolute (1/46); eciliate (17/46), or ciliolate (9/46), or ciliate (20/46), or pilose (1/46). Lemma apex obtuse (2/46), or acute (22/46), or acuminate (17/46), or cuspidate (3/46), or apiculate (1/46), or rostrate (1/46); muticous (36/46), or mucronate (10/46). Palea 0.9–0.9875–1 length of lemma; 4 -veined (1/15), or 5–6 -veined (4/15), or 7 -veined (8/15), or 8 -veined (10/15), or 9–11 -veined (8/15), or 12 -veined (4/15), or 13 -veined (2/15); without keels (4/46), or 2-keeled but the uppermost without keels (3/46), or 2-keeled (39/46). Palea keels eciliate (11/42), or puberulous (1/42), or ciliolate (15/42), or ciliate (15/42). Palea surface glabrous (40/46), or puberulous (3/46), or pubescent (1/46), or pilose (2/46). Palea apex entire (3/17), or dentate (14/17). Apical sterile florets 1 in number (33/33); barren (33/33); rudimentary (1/31), or lanceolate (30/31).

FLOWER Lodicules absent (41/46), or 3 (5/46); glabrous (1/5), or ciliate (4/5). Anthers 6 (46/46), or 7 (1/46). Stigmas 1 (37/38), or 2 (2/38); plumose (31/46), or pubescent (15/46). Ovary unappendaged (17/46), or umbonate (29/46); pubescent on apex (25/28), or pubescent all over (3/28).

FRUIT Caryopsis with adherent pericarp (43/43); linear (2/6), or lanceolate (2/6), or oblong (2/6).

DISTRIBUTION Temperate Asia (6), or Tropical Asia (53).

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