1. Family: Poaceae Barnhart
    1. Nastus Juss.

      1. This genus is accepted, and its native range is W. Indian Ocean.

    [GB]

    nonem

    Habit
    Perennial. Rhizomes short; pachymorph. Culms erect (4/17), or leaning (1/17), or scandent (12/17); 100-1343-2600 cm long; woody. Culm-internodes terete. Lateral branches dendroid. Branch complement three (1/13), or several (1/13), or many (11/13); in a clump (1/1); apparently arising below the node (1), or at the node (24); with subequal branches (2/4), or 1 branch dominant (2/4), or 2 branches dominant (1/4). Culm-sheaths deciduous (1/1); auriculate (1/1). Culm-sheath blade lanceolate (1/4), or narrowly ovate (1/4), or triangular (2/4); constricted at base (2/2). Leaf-sheath auricles absent (23), or erect (1), or falcate (1). Ligule an eciliate membrane (21), or a ciliate membrane (1), or absent (3). Leaf-blade base without a false petiole (8), or with a brief petiole-like connection to sheath (17). Leaf-blades linear (8), or lanceolate (20), or oblong (1); stiff (3), or firm (22). Leaf-blade midrib conspicuous (3/3). Leaf-blade venation without cross veins (24), or with obscure cross veins (1).
    Inflorescences
    Inflorescence a panicle (20/23), or composed of racemes (1/23), or comprising only a few spikelets (2/23); subtended by an unspecialized leaf-sheath (22/23), or a spatheole (1/23); exserted (22/23), or embraced at base by subtending leaf (1/23). Panicle open (12/17), or contracted (5/17). Racemes single (1/1); bearing few fertile spikelets (1/1); bearing 3-4 fertile spikelets on each (1/1). Spikelets solitary (23/23). Fertile spikelets sessile (3/19), or pedicelled (16/19).
    Spikelets
    Spikelets comprising 1-2 basal sterile florets (10/19), or 3 basal sterile florets (2/19), or 4 basal sterile florets (1/19); 1 fertile florets (22/23), or 2 fertile florets (1/23); without rhachilla extension (8/23), or with diminished florets at the apex (15/23). Spikelets lanceolate (7/23), or elliptic (1/23), or oblong (11/23), or ovate (10/23); laterally compressed (22/23), or subterete (1/23); 4.98-11.02-30 mm long; breaking up at maturity (23/23); disarticulating below each fertile floret (23/23).
    Fertile
    Spikelets comprising 1-2 basal sterile florets (10/19), or 3 basal sterile florets (2/19), or 4 basal sterile florets (1/19); 1 fertile florets (22/23), or 2 fertile florets (1/23); without rhachilla extension (8/23), or with diminished florets at the apex (15/23). Spikelets lanceolate (7/23), or elliptic (1/23), or oblong (11/23), or ovate (10/23); laterally compressed (22/23), or subterete (1/23); 4.98-11.02-30 mm long; breaking up at maturity (23/23); disarticulating below each fertile floret (23/23).
    Glume
    Glumes two (7/23), or several (16/23); shorter than spikelet (23/23), or reaching apex of florets (1/23). Lower glume linear (1/22), or lanceolate (2/22), or ovate (20/22); chartaceous (22/22); 1-keeled (1/1); 3 -veined (1/6), or 5 -veined (4/6), or 7 -veined (1/6). Lower glume surface glabrous (21/23), or puberulous (2/23), or pubescent (2/23). Lower glume apex obtuse (1/22), or acute (14/22), or acuminate (5/22), or setaceously attenuate (2/22); muticous (19/22), or mucronate (3/22). Upper glume lanceolate (1/23), or elliptic (1/23), or ovate (22/23); 0.2-0.25-0.3 length of adjacent fertile lemma; chartaceous (22/23), or coriaceous (1/23); without keels (23/23); 3 -veined (1/11), or 5 -veined (3/11), or 7 -veined (5/11), or 9 -veined (2/11). Upper glume surface glabrous (20/23), or puberulous (1/23), or pubescent (3/23), or pilose (1/23). Upper glume apex truncate (1/22), or obtuse (2/22), or acute (13/22), or acuminate (6/22), or setaceously attenuate (1/22); muticous (20/23), or mucronate (3/23).
    Florets
    Basal sterile florets barren (19/19); with palea (5/19), or without significant palea (14/19). Lemma of lower sterile floret elliptic (3/19), or oblong (3/19), or ovate (13/19); 0.4-0.45-0.5 length of fertile lemma; coriaceous (19/19); 5 -veined (3/9), or 6 -veined (1/9), or 7 -veined (3/9), or 8 -veined (1/9), or 9 -veined (3/9), or 10 -veined (1/9), or 11 -veined (3/9); truncate (1/7), or obtuse (3/7), or acute (2/7), or acuminate (3/7); muticous (15/19), or mucronate (4/19). Fertile lemma elliptic (2/23), or oblong (2/23), or ovate (19/23); coriaceous (23/23); without keel (20/23), or keeled (3/23); 7 -veined (6/12), or 8 -veined (2/12), or 9 -veined (6/12), or 10 -veined (2/12), or 11 -veined (4/12), or 12-13 -veined (1/12). Lemma surface glabrous (15/23), or puberulous (3/23), or pubescent (5/23), or pilose (1/23), or hirsute (1/23); hairy on back (9/10), or between veins (1/10). Lemma apex entire (22/23), or dentate (1/23); 3 -fid (1/1); truncate (2/23), or obtuse (5/23), or acute (13/23), or acuminate (5/23); without ornament (21/23), or pubescent (2/23); muticous (21/23), or mucronate (2/23), or awned (1/23); 1 -awned (1/1). Palea 0.9-0.9667-1 length of lemma; coriaceous (23/23); 6 -veined (1/1); without keels (10/23), or 2-keeled (13/23). Palea keels eciliate (10/13), or ciliate (3/13). Palea surface glabrous (19/23), or puberulous (1/23), or pubescent (2/23), or pilose (1/23). Palea apex dentate (3/3). Apical sterile florets 1 in number (15/15); male (1/15), or barren (15/15); rudimentary (1/15), or lanceolate (2/15), or elliptic (13/15).
    Flowers
    Lodicules 3 (23/23); glabrous (14/23), or ciliate (9/23). Anthers 6 (23/23). Stigmas 3 (23/23). Ovary unappendaged (8/23), or umbonate (15/23); pubescent on apex (6/6).
    Fruits
    Caryopsis with adherent pericarp (23/23); obovoid (3/3).
    Distribution
    Africa (12), or Tropical Asia (13), or Pacific (1).

    Images

    Distribution

    Native to:

    Madagascar, Réunion

    Nastus Juss. appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    Gardner, R. [9873], Papua New Guinea K000743027

    First published in Gen. Pl.: 34 (1789)

    Accepted by

    • Govaerts, R. (2019). World Checklist of Vascular Plants (WCVP Database) The Board of Trustees of the Royal Botanic Gardens, Kew.

    Sources

    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 Selected Plant Families 2020. 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 2020. 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