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.

Digitaria

HABIT Annual (109), or perennial (161). Rhizomes absent (220), or short (15), or elongated (34). Stolons absent (247), or present (23). Culms erect (127/222), or geniculately ascending (63/222), or decumbent (58/222), or prostrate (12/222), or rambling (9/222), or leaning (1/222); robust (6/31), or slender (22/31), or weak (3/31); 3–54.63–300 cm long; spongy (1), or firm (258), or wiry (5), or woody (2); without nodal roots (11/42), or with prop roots (1/42), or rooting from lower nodes (40/42). Culm-internodes unequal, the upper longer (1/1); terete (5/7), or elliptical in section (2/7). Culm-nodes constricted (3/4), or swollen (1/4). Lateral branches lacking (25/50), or sparse (13/50), or ample (19/50). Leaf-sheath auricles absent (259), or erect (6). Ligule an eciliate membrane (232), or a ciliolate membrane (31), or a ciliate membrane (2), or a fringe of hairs (1). Leaf-blades filiform (7), or linear (244), or lanceolate (41), or elliptic (1), or oblong (1); herbaceous (263), or chartaceous (1), or coriaceous (1); stiff (3), or firm (255), or flaccid (7). Leaf-blade midrib indistinct (1/8), or evident (2/8), or conspicuous (6/8). Leaf-blade margins unthickened (1/16), or cartilaginous (16/16).

INFLORESCENCE Bisexual (264), or dioecious (1). Inflorescence a panicle (5), or composed of racemes (260), or comprising only a few spikelets (1); terminal (261), or terminal and axillary (4); not deciduous as a whole (259), or deciduous as a whole (6); exserted, or embraced at base by subtending leaf (3). Peduncle persistent (264), or fracturing (1).

Panicle open (5/5). Primary panicle branches not whorled (4/5), or whorled at lower nodes (1/5).

Racemes single (26/260), or paired (73/260), or digitate (152/260), or borne along a central axis (90/260); not compacted (225/226), or in a multilateral false spike (1/226); side by side (175/176), or end to end (1/176); appressed (7/260), or erect (31/260), or ascending (211/260), or spreading (22/260), or radiating (4/260); unilateral (260/260); bearing few fertile spikelets (2/260), or many spikelets (258/260); bearing 2–34–120 fertile spikelets on each. Rhachis wingless (170/260), or narrowly winged (61/260), or broadly winged (33/260); not appreciably folded (93/94), or folded longitudinally to embrace spikelets (1/94), or forming pockets (1/94); flattened (3/220), or angular (216/220), or subterete (1/220). Spikelet packing crowded (2/260), or contiguous (218/260), or lax (25/260), or distant (16/260); 2 -rowed (2/2). Raceme-bases brief (236/260), or filiform (24/260), or linear (2/260).

Spikelets appressed (28/30), or ascending (1/30), or spreading (1/30); solitary (22), or in pairs (164), or in threes (100), or clustered at each node (40). Fertile spikelets sessile (6), or sessile and pedicelled (17), or pedicelled (243); 1–3–25 in the cluster. Pedicels free (260/260), or fused to each other (1/260); filiform (11/13), or linear (1/13), or cuneate (1/13); tip rectangular (9/83), or widened (18/83), or discoid (18/83), or cupuliform (45/83).

STERILE SPIKELETS Basal sterile spikelets absent, or rudimentary (3).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear (1), or lanceolate (82), or elliptic (150), or oblong (53), or ovate (24), or obovate (5), or oblanceolate (1); dorsally compressed; symmetrical (260), or gibbous (5); 0.8–2.543–14 mm long; persistent on plant (2), or falling entire (263). Rhachilla internodes brief up to lowest fertile floret (251), or elongated between glumes (5), or elongated below basal sterile floret (8), or elongated below proximal fertile floret (1).

GLUMES Glumes both absent or obscure (8), or one the lower absent or obscure (135), or one to two the lower present in some spikelets (2), or two (132); shorter than spikelet (194/254), or reaching apex of florets (65/254), or exceeding apex of florets (2/254); thinner than fertile lemma (247/261), or similar to fertile lemma in texture (14/261). Lower glume lanceolate (1/134), or elliptic (2/134), or oblong (10/134), or ovate (95/134), or orbicular (4/134), or oblate (27/134); clasping (9/9); 0.33 length of upper glume; hyaline (68/119), or membranous (51/119); without keels (60/60); 0 -veined (98/104), or 1 -veined (9/104), or 2 -veined (1/104), or 3 -veined (2/104). Lower glume lateral veins absent (103/134), or obscure (1/134), or distinct (30/134). Lower glume surface without pits (134/134); glabrous (132/134), or pubescent (2/134), or setose (1/134). Lower glume apex entire (131/134), or erose (2/134), or dentate (1/134); 2 -fid (1/1); emarginate (5/118), or truncate (52/118), or obtuse (68/118), or acute (28/118), or acuminate (1/118). Upper glume linear (2/261), or lanceolate (64/261), or elliptic (119/261), or oblong (42/261), or ovate (40/261), or orbicular (2/261), or oblate (3/261), or obovate (1/261); not gibbous (249/261), or gibbous (6/261), or spurred (6/261); hyaline (16/258), or membranous (241/258), or chartaceous (1/258); with undifferentiated margins (260/261), or hyaline margins (1/261); without keels (228/228); 0 -veined (16/258), or 1 -veined (15/258), or 2 -veined (7/258), or 3 -veined (194/258), or 4 -veined (35/258), or 5 -veined (73/258), or 6 -veined (6/258), or 7 -veined (14/258). Upper glume lateral veins without ribs (246/247), or ribbed (1/247); without cross-veins (2/10), or transversely connected at apex (8/10); meeting at apex (1/1). Upper glume surface smooth (259/261), or scabrous (2/261); glabrous (69/261), or puberulous (26/261), or pubescent (135/261), or pilose (38/261), or hirsute (3/261), or villous (27/261), or hispid (1/261), or setose (2/261), or woolly (1/261); with simple hairs (152/210), or capitate hairs (24/210), or clavate hairs (20/210), or verruculose hairs (17/210). Upper glume apex entire (260/261), or erose (1/261), or dentate (1/261); 2 -fid (1/1); emarginate (7/247), or truncate (10/247), or obtuse (40/247), or acute (196/247), or acuminate (9/247), or setaceously attenuate (1/247).

FLORETS Basal sterile florets barren; with palea (17), or without significant palea (249). Lemma of lower sterile floret lanceolate (42), or elliptic (184), or oblong (39), or ovate (11), or orbicular (1), or obovate (1); 1.1 length of fertile lemma; hyaline (1/264), or membranous (261/264), or chartaceous (1/264), or cartilaginous (1/264); 1–6–13 -veined; without ribs (252/264), or ribbed (12/264); without grooves (262), or sulcate (2), or with 2 longitudinal grooves (2); truncate (3/251), or obtuse (19/251), or acute (219/251), or acuminate (17/251), or rostrate (1/251); muticous (264), or awned (1). Palea of lower sterile floret hyaline (16/17), or membranous (1/17). Fertile florets bisexual (264), or female (1). Fertile lemma lanceolate (41), or elliptic (192), or oblong (29), or ovate (19), or obovate (2); not gibbous (254), or gibbous (11); chartaceous (2), or cartilaginous (263); much thinner on margins; without keel (252/263), or keeled (11/263); wingless; 3 -veined (28/30), or 5 -veined (1/30), or 7 -veined (1/30). Lemma lateral veins obscure (6/6). Lemma surface smooth (201), or granulose (3), or scaberulous (1), or papillose (2), or striate (44), or reticulate (8), or punctate (8); unwrinkled (264), or rugulose (1); without grooves; glabrous (264), or puberulous (1); hairy in lines (1/1); with clavate hairs (1/1). Lemma margins covering most of palea; eciliate (261), or ciliate (4). Lemma apex obtuse (3/246), or acute (162/246), or acuminate (45/246), or apiculate (46/246), or rostrate (2/246); muticous (261), or mucronate (3), or awned (2); 1 -awned (1/1). Palea 0.9–0.9909–1 length of lemma; cartilaginous.

FLOWER Lodicules 2 (15/15); free (14/15), or united (1/15); membranous (4/4); truncate (6/6). Anthers 3 (85/85).

FRUIT Caryopsis with adherent pericarp (40/40); ellipsoid (6/15), or oblong (3/15), or ovoid (5/15), or obovoid (1/15); dorsally compressed (2/6), or flattened (4/6); plano-convex (1/1). Embryo 0.33–0.4243–0.5 length of caryopsis. Hilum punctiform (17/21), or elliptic (4/21).

MALE Male inflorescence similar to female (1/1). Male spikelets resembling female (1/1).

DISTRIBUTION Europe (4), or Africa (112), or Temperate Asia (31), or Tropical Asia (57), or Australasia (47), or Pacific (21), or North America (38), or South America (80), or Antarctica (1).

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