1. Family: Poaceae Barnhart
    1. Acroceras Stapf

      1. This genus is accepted, and its native range is Tropics & Subtropics.

    [FZ]

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

    Inflorescences
    Inflorescence of loose racemes along a central axis bearing paired spikelets, but sometimes approaching a panicle due to irregular secondary branching (true panicle in A. attenuatum).
    Spikelets
    Spikelets dorsally or weakly laterally compressed.
    Glume
    Inferior glume 1/2–3/4 length of spikelet; superior glume and inferior lemma thickened and laterally compressed at apex as if nipped by pincers (A. attenuatum scarcely so).
    Lemma
    Superior lemma dorsally compressed, crustaceous, with a little green crest at apex; palea apex usually reflexed and slightly protruding from lemma, usually bearing 2 green spots.
    [GB]

    nonem

    Habit
    Annual (7), or perennial (10). Rhizomes absent (16), or elongated (1). Stolons absent (16), or present (1). Culms erect (2), or decumbent (13), or prostrate (2), or rambling (4); weak (2/2); 5-52.5-200 cm long; rooting from lower nodes (14/14). Lateral branches sparse (2/3), or ample (1/3). Ligule an eciliate membrane (12), or a ciliolate membrane (5), or a fringe of hairs (1), or absent (1). Leaf-blades linear (7), or lanceolate (13), or oblong (1), or ovate (1); firm (16), or flaccid (1). Leaf-blade midrib evident (1/2), or conspicuous (1/2). Leaf-blade venation without cross veins (14), or with obscure cross veins (3), or with distinct cross veins (1). Leaf-blade margins cartilaginous (2/2).
    Inflorescences
    Inflorescence a panicle (3), or composed of racemes (13), or comprising only a few spikelets (1); terminal (16), or terminal and axillary (1). Panicle open (2/2). Racemes borne along a central axis (13/13); appressed (1/13), or ascending (12/13); unilateral (13/13). Rhachis wingless (12/13), or narrowly winged (1/13); angular (9/9). Spikelet packing contiguous (6/13), or lax (5/13), or distant (2/13). Spikelets appressed (1/7), or ascending (6/7); solitary (7), or in pairs (15). Fertile spikelets sessile (1), or sessile and pedicelled (2), or pedicelled (14); 1 in the cluster (3/11), or 2 in the cluster (11/11). Pedicels free (15/16), or fused to each other (1/16); filiform (1/12), or linear (11/12).
    Spikelets
    Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate (2), or elliptic (9), or oblong (2), or ovate (3), or obovate (1); laterally compressed (12), or subterete (4), or dorsally compressed (1); 1.5-3.612-6.5 mm long; falling entire. Spikelet callus brief (15), or square (2); glabrous (10/10); base truncate (11/11). Rhachilla internodes brief up to lowest fertile floret (12), or elongated between glumes (5).
    Fertile
    Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate (2), or elliptic (9), or oblong (2), or ovate (3), or obovate (1); laterally compressed (12), or subterete (4), or dorsally compressed (1); 1.5-3.612-6.5 mm long; falling entire. Spikelet callus brief (15), or square (2); glabrous (10/10); base truncate (11/11). Rhachilla internodes brief up to lowest fertile floret (12), or elongated between glumes (5).
    Glume
    Glumes shorter than spikelet (9), or reaching apex of florets (8); thinner than fertile lemma. Lower glume lanceolate (1), or elliptic (1), or ovate (15); clasping (5/5); membranous (2), or herbaceous (15); without keels (16), or 1-keeled (1); 3 -veined (13), or 4 -veined (2), or 5 -veined (6), or 6-7 -veined (2). Lower glume surface smooth (16), or asperulous (1), or rugose (1); glabrous (13), or puberulous (3), or pubescent (1), or pilose (1). Lower glume apex obtuse (3), or acute (10), or acuminate (1), or cuspidate (2), or laterally pinched (1); muticous (15), or mucronate (2), or awned (1). Upper glume lanceolate (2), or elliptic (7), or ovate (9); membranous (2), or herbaceous (15); without keels (5/6), or 1-keeled (1/6); 3 -veined (1), or 5 -veined (13), or 7 -veined (2), or 9-11 -veined (1). Upper glume surface smooth (14), or asperulous (1), or rugose (2); glabrous (10), or puberulous (5), or pubescent (1), or pilose (1). Upper glume apex obtuse (3/16), or acute (3/16), or acuminate (1/16), or laterally pinched (9/16); muticous (15), or mucronate (2).
    Florets
    Basal sterile florets male (10), or barren (9); with palea (14), or without significant palea (3). Lemma of lower sterile floret lanceolate (2), or elliptic (3), or oblong (3), or ovate (9); 1 length of fertile lemma; membranous (2), or herbaceous (15); 3 -veined (1/13), or 5 -veined (10/13), or 7 -veined (1/13), or 11 -veined (1/13); obtuse (4), or acute (5), or laterally pinched at apex (8); muticous (15), or mucronate (2). Palea of lower sterile floret hyaline (13/14), or membranous (1/14). Fertile lemma lanceolate (1), or elliptic (10), or oblong (1), or ovate (4), or oblanceolate (1); dorsally compressed; lanceolate in profile (1/1); coriaceous (1), or indurate (16); 3 -veined (1/2), or 5 -veined (1/2). Lemma surface smooth (14), or papillose (1), or striate (2). Lemma margins involute. Lemma apex obtuse (2), or acute (11), or apiculate (4); without ornament (4), or laterally pinched (2), or with a little green crest (11), or with a green spot (2), or with a shallow excavation (2), or pubescent (5); muticous (13), or mucronate (4). Palea embraced by lemma (7), or reflexed at apex (10); not rolled (1), or involute (16); 1 length of lemma; coriaceous (1), or indurate (16); 2 -veined (11/11); without keels (5), or 2-keeled (12). Palea apex lobed (1/1).
    Flowers
    Lodicules 2 (3/3); fleshy (1/1); irregularly toothed (1/1). Anthers 2 (1/5), or 3 (4/5). Stigmas 2 (1/1).
    Fruits
    Caryopsis with adherent pericarp (4/4); ellipsoid (1/2), or oblong (1/2); dorsally compressed (1/1); plano-convex (1/1). Embryo 0.4-0.475-0.5 length of caryopsis. Hilum punctiform (2/3), or linear (1/3); 1 length of caryopsis.
    Distribution
    Africa (11), or Temperate Asia (3), or Tropical Asia (3), or North America (1), or South America (5).
    [FTEA]

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

    Habit
    Annuals or perennials with slender trailing culms, often rooting from the lower nodes
    Leaves
    Leaf-blades linear to ovate, with or without cross-veins; ligule a very short membranous rim
    Inflorescences
    Inflorescence composed of racemes borne along a central axis; rhachis triquetrous, bearing spikelets in pairs (or sometimes on short secondary branchlets), the pedicels of each pair ± connate below
    Spikelets
    Spikelets lanceolate to oblong, plumply subterete, the glumes and lemmas ± thickened at the extreme tip; glumes unequal, membranous, the lower 1/4–3/4, the upper as long as the spikelet; lower floret ♂ or barren, the lemma similar to the upper glume, with a palea; upper lemma crustaceous, dorsally compressed, smooth or finely striate, its margins inrolled and clasping the edges of the palea, glabrous or obscurely puberulous at the green keeled tip; upper palea subacute with the tip briefly reflexed and ± protruberant between the lemma margins
    Fruits
    Caryopsis ellipsoid, flattened on one side.

    Images

    Distribution

    Native to:

    Angola, Argentina Northeast, Assam, Bangladesh, Belize, Benin, Bolivia, Borneo, Botswana, Brazil North, Brazil Northeast, Brazil South, Brazil Southeast, Brazil West-Central, Burkina, Burundi, Cambodia, Cameroon, Cape Provinces, Central African Repu, Chad, China South-Central, Colombia, Comoros, Congo, Costa Rica, Cuba, Dominican Republic, East Himalaya, Ecuador, Equatorial Guinea, Ethiopia, French Guiana, Gabon, Gambia, Ghana, Guatemala, Guinea, Guinea-Bissau, Gulf of Guinea Is., Guyana, Hainan, Haiti, Honduras, India, Ivory Coast, Jamaica, Jawa, Kenya, KwaZulu-Natal, Laos, Lesser Sunda Is., Liberia, Madagascar, Malawi, Malaya, Mali, Maluku, Mauritania, Mexico Central, Mexico Gulf, Mexico Northeast, Mexico Southeast, Mexico Southwest, Mozambique, Myanmar, Namibia, New Guinea, Nicaragua, Niger, Nigeria, Northern Provinces, Panamá, Paraguay, Peru, Philippines, Réunion, Senegal, Sierra Leone, Sri Lanka, Sudan, Sulawesi, Sumatera, Suriname, Tanzania, Thailand, Togo, Trinidad-Tobago, Uganda, Uruguay, Venezuela, Vietnam, Zambia, Zaïre, Zimbabwe

    Acroceras Stapf appears in other Kew resources:

    First published in D.Oliver & auct. suc. (eds.), Fl. Trop. Afr. 9: 621 (1920)

    Accepted by

    • Govaerts, R.H.A. (2011). World checklist of selected plant families published update Facilitated by the Trustees of the Royal Botanic Gardens, Kew.

    Literature

    Flora of West Tropical Africa
    • in F.T.A. 9: 621 (1920).
    Flora Zambesiaca
    • in F.T.A. 9: 621 (1920).
    Flora of Tropical East Africa
    • in F.T.A. 9: 621 (1920)

    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

    GrassBase - The Online World Grass Flora
    http://creativecommons.org/licenses/by-nc-sa/3.0

    Kew Backbone Distributions
    The International Plant Names Index and World Checklist of Selected Plant Families 2019. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

    Kew Names and Taxonomic Backbone
    The International Plant Names Index and World Checklist of Selected Plant Families 2019. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0