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.

Axonopus

HABIT Annual (8), or perennial (85). Rhizomes absent (75), or short (14), or elongated (9). Stolons absent (76), or present (19). Culms erect (39/49), or geniculately ascending (16/49), or decumbent (5/49); robust (14/27), or slender (12/27), or weak (1/27); 3–70.1–260 cm long; firm (89), or wiry (2); without nodal roots (1/1), or rooting from lower nodes (1/1). Culm-internodes terete (8/29), or elliptical in section (23/29). Culm-nodes flush with internodes (1/3), or swollen (2/3). Lateral branches lacking (20/31), or sparse (7/31), or ample (7/31). Leaves differentiated into sheath and blade (74), or without demarcation between sheath and blade (17). Leaf-sheaths open for most of their length (1/1). Leaf-sheath auricles absent (90), or erect (3). Ligule an eciliate membrane (1), or a ciliolate membrane (73), or a ciliate membrane (13), or a fringe of hairs (4), or absent (1). Leaf-blade base without a false petiole (90), or with a brief petiole-like connection to sheath (1). Leaf-blades persistent (90), or deciduous at the ligule (6); filiform (5), or linear (86), or lanceolate (10), or oblong (1); stiff (21), or firm (70). Leaf-blade midrib conspicuous (4/4). Leaf-blade apex muticous (90), or pungent (2).

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme (1), or composed of racemes; terminal (81), or terminal and axillary (13).

Racemes single (3), or paired (24), or digitate (71), or borne along a central axis (12); erect (9), or ascending (77), or spreading (21), or drooping (2), or deflexed (1); unilateral. Rhachis wingless (87), or narrowly winged (3), or broadly winged (1); membranous (1/1); not appreciably folded (2/4), or folded longitudinally to embrace spikelets (2/4); flattened (2/87), or angular (85/87); terminating in a spikelet (88), or barren extension (3). Spikelet packing adaxial; contiguous (90), or lax (1); 1 -rowed (1/17), or 2 -rowed (16/17). Raceme-bases brief (89), or filiform (1), or linear (2).

Spikelets sunken (1/90), or appressed (89/90); solitary. Fertile spikelets sessile (62), or pedicelled (35). Pedicels oblong (3/28), or reduced to a stump (26/28); tip rectangular (1/2), or cupuliform (1/2).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate (10), or elliptic (44), or oblong (33), or ovate (42), or obovate (4); of unremarkable solid shape (90), or turbinate (1); dorsally compressed; 1.1–2.484–5.1 mm long; falling entire. Floret callus glabrous (1/1), or pubescent (1/1).

GLUMES Glumes one the lower absent or obscure, or two (1); shorter than spikelet (2), or reaching apex of florets (86), or exceeding apex of florets (4); thinner than fertile lemma; parallel to lemmas (90), or gaping (1). Lower glume lanceolate (1/1); 1–5 -veined (1/1). Lower glume surface without pits (1/1). Upper glume lanceolate (1/34), or elliptic (18/34), or oblong (1/34), or ovate (14/34); not gibbous (90), or spurred (1); 1–1.1–1.5 length of adjacent fertile lemma; hyaline (7), or membranous (84); without keels (31/31); 0–1 -veined (1/88), or 2 -veined (35/88), or 3 -veined (24/88), or 4 -veined (31/88), or 5 -veined (45/88), or 6 -veined (7/88), or 7 -veined (10/88), or 9 -veined (1/88). Upper glume lateral veins without ribs (88), or ribbed (3). Upper glume surface smooth (88), or asperulous (2), or scabrous (1); glabrous (56), or puberulous (24), or pubescent (26), or pilose (5), or villous (1); with simple hairs (54/55), or tubercle-based hairs (1/55); without hair tufts (89), or with a transverse fringe of hair (1), or with an apical beard (5). Upper glume apex entire (89), or erose (1), or dentate (1); 3 -fid (1/1); obtuse (9/14), or acute (5/14).

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate (2/34), or elliptic (19/34), or oblong (1/34), or ovate (12/34); 0.9–1.101–2 length of fertile lemma; hyaline (5/9), or membranous (4/9); 0–1 -veined (1/89), or 2 -veined (37/89), or 3 -veined (24/89), or 4 -veined (31/89), or 5 -veined (45/89), or 6–7 -veined (10/89), or 9 -veined (1/89); without ribs (88), or ribbed (3); emarginate (1/14), or obtuse (4/14), or acute (9/14); muticous (32/34), or awned (2/34). Fertile lemma linear (2/39), or elliptic (23/39), or oblong (6/39), or ovate (7/39), or obovate (3/39); dorsally compressed (2/2); membranous (2), or coriaceous (1), or indurate (88); of similar consistency above (90), or much thinner above (1); without keel (90/90); wingless; 4 -veined (1/1). Lemma surface smooth (80), or papillose (7), or striate (4); unwrinkled; without grooves; without hair tufts (90), or with conspicuous apical hairs (1). Lemma margins flat (2), or involute (89); exposing palea (90), or covering most of palea (1). Lemma apex obtuse (38/66), or acute (29/66), or acuminate (2/66); without ornament (48), or scabrous (2), or pubescent (45). Palea embraced by lemma (90), or gaping (1); not rolled (3), or involute (88); 1 length of lemma; hyaline (1), or membranous (1), or coriaceous (1), or indurate (88); 2 -veined (2/2). Palea apex dentate (2/2).

FLOWER Lodicules 2 (10/10); fleshy (3/3); irregularly toothed (1/1). Anthers 2 (2/24), or 3 (22/24). Stigmas 2 (2/2); plumose (90), or sparsely hairy (1).

FRUIT Caryopsis with adherent pericarp (75/75); ellipsoid (3/5), or oblong (1/5), or ovoid (1/5), or obovoid (2/5). Embryo 0.33–0.455–0.5 length of caryopsis. Hilum punctiform (2/3), or elliptic (2/3); 0.25 length of caryopsis.

DISTRIBUTION Africa (3), or Temperate Asia (2), or Tropical Asia (2), or Australasia (2), or Pacific (3), or North America (13), or South America (86).

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