Poaceae

Axonopus P.Beauv.

First published in Ess. Agrostogr.: 12 (1812)
This genus is accepted
The native range of this genus is Tropical Africa, Central U.S.A. to Tropical & Subtropical America, Easter Island.

Descriptions

nonem

Morphology General Habit
Annual (6), or perennial (83). Rhizomes absent (72), or short (13), or elongated (9). Stolons absent (72), or present (19). Culms erect (36/45), or geniculately ascending (14/45), or decumbent (5/45); robust (14/27), or slender (12/27), or weak (1/27); 6-70.81-260 cm long; firm (85), or wiry (2); without nodal roots (1/1), or rooting from lower nodes (1/1). Culm-internodes terete (7/28), or elliptical in section (23/28). Culm-nodes flush with internodes (1/3), or swollen (2/3). Lateral branches lacking (18/29), or sparse (7/29), or ample (7/29). Leaves differentiated into sheath and blade (70), or without demarcation between sheath and blade (17). Leaf-sheath auricles absent (86), or erect (3). Ligule an eciliate membrane (1), or a ciliolate membrane (71), or a ciliate membrane (13), or a fringe of hairs (2). Leaf-blades persistent (86), or deciduous at the ligule (6); filiform (3), or linear (84), or lanceolate (9); stiff (21), or firm (66). Leaf-blade midrib conspicuous (4/4). Leaf-blade apex muticous (86), or pungent (2).
Morphology Reproductive morphology Inflorescences
Inflorescence composed of racemes; terminal (79), or terminal and axillary (11). Racemes single (1), or paired (24), or digitate (70), or borne along a central axis (11); erect (9), or ascending (74), or spreading (21), or drooping (1), or deflexed (1); unilateral. Rhachis wingless (86), or narrowly winged (1); flattened (2/85), or angular (83/85); terminating in a spikelet (86), or barren extension (1). Spikelet packing adaxial; contiguous (86), or lax (1); 2 -rowed (16/16). Raceme-bases brief (86), or linear (2). Spikelets sunken (1), or appressed (86); solitary. Fertile spikelets sessile (58), or pedicelled (35). Pedicels oblong (3/28), or reduced to a stump (26/28); tip rectangular (1/2), or cupuliform (1/2).
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate (9), or elliptic (43), or oblong (32), or ovate (41), or obovate (3); dorsally compressed; 1.1-2.485-5.1 mm long; falling entire. Floret callus glabrous (1/1), or pubescent (1/1).
Fertile
Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate (9), or elliptic (43), or oblong (32), or ovate (41), or obovate (3); dorsally compressed; 1.1-2.485-5.1 mm long; falling entire. Floret callus glabrous (1/1), or pubescent (1/1).
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes one the lower absent or obscure, or two (1); shorter than spikelet (2), or reaching apex of florets (83), or exceeding apex of florets (3); thinner than fertile lemma; parallel to lemmas (86), or gaping (1). Lower glume lanceolate (1/1); 1-5 -veined (1/1). Upper glume elliptic (17/30), or oblong (1/30), or ovate (12/30); 1-1.1-1.5 length of adjacent fertile lemma; hyaline (5), or membranous (82); without keels (28/28); 0-1 -veined (1/85), or 2 -veined (33/85), or 3 -veined (22/85), or 4 -veined (30/85), or 5 -veined (44/85), or 6 -veined (7/85), or 7 -veined (10/85), or 9 -veined (1/85). Upper glume lateral veins without ribs (84), or ribbed (3). Upper glume surface glabrous (53), or puberulous (24), or pubescent (25), or pilose (5), or villous (1); with simple hairs (53/54), or tubercle-based hairs (1/54); without hair tufts (86), or with an apical beard (5). Upper glume apex entire (86), or dentate (1); 3 -fid (1/1); obtuse (8/11), or acute (3/11).
Morphology Reproductive morphology Flowers Florets
Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic (17/30), or oblong (1/30), or ovate (12/30); 0.9-1.102-2 length of fertile lemma; hyaline (3/6), or membranous (3/6); 0-1 -veined (1/85), or 2 -veined (34/85), or 3 -veined (22/85), or 4 -veined (31/85), or 5 -veined (45/85), or 6-7 -veined (10/85), or 9 -veined (1/85); without ribs (84), or ribbed (3); obtuse (3/11), or acute (8/11). Fertile lemma linear (2/35), or elliptic (22/35), or oblong (5/35), or ovate (6/35), or obovate (2/35); coriaceous (1), or indurate (86); without keel; 4 -veined (1/1). Lemma surface smooth (77), or papillose (6), or striate (4); without hair tufts (86), or with conspicuous apical hairs (1). Lemma margins involute. Lemma apex obtuse (37/62), or acute (26/62), or acuminate (2/62); without ornament (46), or scabrous (2), or pubescent (43). Palea involute; coriaceous (1), or indurate (86).
Morphology Reproductive morphology Flowers
Lodicules 2 (8/8); fleshy (3/3). Anthers 3 (21/21).
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp (73/73); ellipsoid (3/3), or obovoid (1/3). Embryo 0.5 length of caryopsis. Hilum punctiform (1/1).
Distribution
Africa (3), or Temperate Asia (2), or Tropical Asia (2), or Australasia (2), or Pacific (3), or North America (13), or South America (82).
[GB]

George R. Proctor (2012). Flora of the Cayman Isands (Second Edition). Royal Botanic Gardens, Kew

Morphology General Habit
annual to robust perennial herbs, erect or decumbent, branched or unbranched, the internodes solid, the leaf-sheaths smooth or scabrous; ligule a ciliate membrane or a fringe of hairs
Morphology Leaves
Leaf-blades filiform to lanceolate, flat, conduplicate or involute, the margins smooth or scabrous
Morphology Reproductive morphology Inflorescences
Inflorescence with spreading primary branches having 1-sided or distichous spikelets; secondary branches (if present) appressesed; rachis terminating in a spikelet; callus not differentiated
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets disarticulating at base, dorsiventrally compressed or plano-convex; lower glume absent, upper glume as long as the spikelet
Morphology Reproductive morphology Flowers Florets
Lower floret lemma membranous; upper floret lemma 0.5–1-times the length of the lower floret lemma, cartilaginous and smooth or muricate, shiny or dull, mostly with involute margins
Morphology Reproductive morphology Seeds
Seed with white or grayish embryo.
Distribution
A tropical and subtropical genus with about 110 species.
[Cayman]

Gramineae, W. D. Clayton, S. M. Phillips And S. A. Renvoize. Flora of Tropical East Africa. 1974

Morphology General Habit
Caespitose or stoloniferous perennials, rarely annuals
Morphology Leaves
Leaf-blades flat to involute; ligule short, membranous
Morphology Reproductive morphology Inflorescences
Inflorescence composed of 2-many slender racemes, these digitate or borne upon a short common axis, rarely solitary; rhachis triquetrous, glabrous to villous, bearing single spikelets, their lower lemma adaxial
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets lanceolate to oblong, dorsally compressed, small; lower glume absent; upper glume membranous, as long as the spikelet; lower floret barren, without a palea, resembling the upper glume; upper lemma ± crustaceous, usually obtuse, the margins inrolled and clasping only the edges of the obtuse palea
Morphology Reproductive morphology Fruits
Caryopsis elliptic, dorsally compressed
Distribution
Species ± 110; tropics, but most of the species confined to South America.
[FTEA]

Gramineae, W. D. Clayton. Flora Zambesiaca 10:3. 1989

Morphology Reproductive morphology Inflorescences
Inflorescence of 2–many racemes, mostly subdigitate but sometimes along a central axis, the spikelets single and adaxial.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets thinly biconvex, lanceolate to oblong-elliptic.
Morphology Reproductive morphology Inflorescences Bracts Glume
Inferior glume absent. Superior glume as long as spikelet; inferior lemma similar, without a palea.
Morphology Reproductive morphology Inflorescences Bracts Lemma
Superior lemma crustaceous, granulose.
[FZ]

nonem

Morphology General Habit
Annual (1), or perennial (1). Culms erect (1), or geniculately ascending (1); 3-33.12-78 cm long. Lateral branches lacking (1/1). Leaf-sheaths open for most of their length (1/1). Ligule a fringe of hairs. Leaf-blades filiform.
Morphology Reproductive morphology Inflorescences
Inflorescence composed of racemes; terminal (1), or terminal and axillary (1). Racemes single; ascending (1), or drooping (1); unilateral. Rhachis narrowly winged (1), or broadly winged (1); membranous (1/1); folded longitudinally to embrace spikelets; terminating in a barren extension. Spikelet packing adaxial. Spikelets appressed; solitary. Fertile spikelets sessile.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate (1), or ovate (1); dorsally compressed; 1.4-2.1-3.1 mm long; falling entire.
Fertile
Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate (1), or ovate (1); dorsally compressed; 1.4-2.1-3.1 mm long; falling entire.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes one the lower absent or obscure; reaching apex of florets; thinner than fertile lemma. Upper glume lanceolate (1), or ovate (1); hyaline; without keels; 2 -veined (1/1). Upper glume surface asperulous (1), or scabrous (1). Upper glume apex entire (1), or erose (1); acute.
Morphology Reproductive morphology Flowers Florets
Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; hyaline; 2 -veined; emarginate (1), or acute (1); awned. Fertile lemma oblong (1), or ovate (1); dorsally compressed; membranous; of similar consistency above (1), or much thinner above (1); without keel. Lemma margins exposing palea (1), or covering most of palea (1). Lemma apex acute. Palea embraced by lemma (1), or gaping (1); 1 length of lemma; hyaline (1), or membranous (1); 2 -veined. Palea apex dentate.
Morphology Reproductive morphology Flowers
Lodicules 2 (1/1). Anthers 2. Stigmas 2 (1/1).
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp; oblong (1), or ovoid (1), or obovoid (1). Embryo 0.33-0.4325-0.5 length of caryopsis. Hilum punctiform (1), or elliptic; 0.25 length of caryopsis.
Distribution
South America.
[GB]

nonem

Morphology General Habit
Annual. Culms erect; 10-75 cm long. Ligule a ciliolate membrane.
Morphology Reproductive morphology Inflorescences
Inflorescence composed of racemes. Racemes digitate; unilateral. Rhachis narrowly winged; angular. Spikelet packing adaxial; 1 -rowed. Spikelets solitary. Fertile spikelets sessile.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets obovate; turbinate; dorsally compressed; 3.5-4 mm long; falling entire.
Fertile
Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets obovate; turbinate; dorsally compressed; 3.5-4 mm long; falling entire.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes one the lower absent or obscure; exceeding apex of florets; thinner than fertile lemma. Upper glume ovate; spurred; membranous; without keels; 3 -veined. Upper glume surface pubescent; with a transverse fringe of hair. Upper glume apex obtuse.
Morphology Reproductive morphology Flowers Florets
Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; membranous; 3 -veined; obtuse. Fertile lemma obovate; indurate. Lemma margins involute. Lemma apex obtuse; pubescent. Palea indurate.
Distribution
South America.
[GB]

Sources

  • Flora Zambesiaca

    • Flora Zambesiaca
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Flora of Tropical East Africa

    • Flora of Tropical East Africa
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Flora of the Cayman Islands

    • Flora of the Cayman Islands
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • GrassBase - The Online World Grass Flora

    • Clayton, W.D., Vorontsova, M.S., Harman, K.T. and Williamson, H. (2006 onwards). GrassBase - The Online World Grass Flora.
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Herbarium Catalogue Specimens

    • 'The Herbarium Catalogue, Royal Botanic Gardens, Kew. Published on the Internet http://www.kew.org/herbcat [accessed on Day Month Year]'. Please enter the date on which you consulted the system.

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0