1. Family: Poaceae Barnhart
    1. Genus: Panicum L.
      1. Panicum trachyrhachis Benth.

        This species is accepted, and its native range is Indo-China, Lesser Sunda Islands to N. Australia.

    [GB]
    Habit
    Annual. Culms erect; 60-180 cm long; 3-6 -noded. Culm-nodes glabrous. Leaf-sheaths smooth; glabrous on surface, or pilose; outer margin glabrous. Ligule a ciliate membrane; 1.2-3 mm long. Leaf-blades flat, or involute; 12-45 cm long; 3-7 mm wide. Leaf-blade surface smooth, or scabrous; glabrous. Leaf-blade margins smooth.
    Inflorescences
    Inflorescence a panicle. Panicle open; ovate; 30-65 cm long. Primary panicle branches spreading; whorled at lower nodes; 15-30 cm long; bearing 40-100 fertile spikelets on each lower branch. Panicle axis scabrous. Panicle branches scabrous; glabrous in axils. Spikelets solitary. Fertile spikelets pedicelled. Pedicels 0.8-2.5 mm long; scabrous.
    Spikelets
    Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; compressed slightly; 3.1-3.9 mm long; 1-1.1 mm wide; falling entire. Rhachilla internodes elongated between glumes. Rhachilla elongation 0.3-0.4 mm long.
    Fertile
    Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; compressed slightly; 3.1-3.9 mm long; 1-1.1 mm wide; falling entire. Rhachilla internodes elongated between glumes. Rhachilla elongation 0.3-0.4 mm long.
    Glume
    Glumes reaching apex of florets; thinner than fertile lemma. Lower glume lanceolate; 2.1-2.9 mm long; 0.66-0.75 length of spikelet; membranous; without keels; 3-5 -veined. Lower glume lateral veins thickened. Lower glume apex acute, or acuminate; awned; 1 -awned. Lower glume awn 0.8-1.2 mm long. Upper glume lanceolate; 1 length of spikelet; membranous; without keels; 7 -veined. Upper glume inner surface pubescent (at tip). Upper glume apex acute; muticous, or awned; 1 -awned. Upper glume awn 0-1 mm long.
    Florets
    Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; lanceolate; 1 length of spikelet; membranous; 9 -veined; acute, or acuminate; mucronate. Fertile lemma elliptic; dorsally compressed; 2.1-2.4 mm long; indurate; without keel. Lemma lateral veins distinct. Lemma margins involute. Lemma apex obtuse. Palea involute; indurate.
    Flowers
    Anthers 3; 1.1-1.4 mm long.
    Fruits
    Caryopsis with adherent pericarp.
    Distribution
    Asia-tropical: Indo-China, Malesia, and Papuasia. Australasia: Australia.
    Reference
    Paniceae. Webster 1993.
    [GB]
    Habit
    Annual; caespitose; clumped loosely. Culms erect, or geniculately ascending; robust; 80-180 cm long; 3-5 -noded. Lateral branches lacking, or sparse. Leaf-sheaths mostly shorter than adjacent culm internode; without keel. Ligule a ciliate membrane; 2 mm long. Leaf-blades 10-35 cm long; 5-10 mm wide. Leaf-blade midrib conspicuous. Leaf-blade surface hispid; with tubercle-based hairs. Leaf-blade margins scaberulous.
    Inflorescences
    Inflorescence a panicle. Panicle open; ovate; effuse; 25-40 cm long. Primary panicle branches spreading; 10-18 cm long. Panicle branches scabrous. Spikelets solitary. Fertile spikelets pedicelled. Pedicels angular; 2-4 mm long; scabrous.
    Spikelets
    Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 4.5-5 mm long; 1 mm wide; falling entire. Rhachilla internodes elongated between glumes.
    Fertile
    Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 4.5-5 mm long; 1 mm wide; falling entire. Rhachilla internodes elongated between glumes.
    Glume
    Glumes similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 4.5-5 mm long; 1 length of spikelet; membranous; without keels; 5-7 -veined. Lower glume apex acuminate. Upper glume lanceolate; 3.5-4 mm long; 0.7-0.8 length of spikelet; membranous; without keels; 5-7 -veined. Upper glume apex acute.
    Florets
    Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; lanceolate; 3.5-4 mm long; 0.7-0.8 length of spikelet; membranous; 5-7 -veined; acute. Fertile lemma elliptic; dorsally compressed; 2 mm long; indurate; yellow; without keel. Lemma margins involute. Lemma apex obtuse. Palea involute; indurate.
    Flowers
    Anthers 3; 1.5 mm long.
    Fruits
    Caryopsis 2 mm long.
    Distribution
    Australasia: Australia.
    Reference
    Paniceae. Simon 1995.

    Images

    Distribution

    Native to:

    Laos, Lesser Sunda Is., New Guinea, Northern Territory, Queensland, Thailand, Vietnam

    Panicum trachyrhachis Benth. appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    Schultz, F. [343], Northern Territory K000674357 holotype
    Elsey, J. R. [s.n.], Northern Territory K000674354
    Elsey, J. R. [s.n.], Northern Territory K000674356
    McKinley, A. [s.n.], Northern Territory K000674355
    Kerr, A.F.G. [9581], Thailand Panicum kerrii K000290300 holotype
    Kerr, A.F.G. [9581], Thailand Panicum kerrii K000290298 holotype
    Kerr, A.F.G. [9581], Thailand Panicum kerrii K000290299 holotype
    Nov 13, 1991 Simon, B. K. [3370], Queensland Panicum robustum K000674383 isotype

    First published in Fl. Austral. 7: 490 (1878)

    Accepted by

    • Newman, M., Ketphanh, S., Svengsuksa, B., Thomas, P., Sengdala, K., Lamxay, V. & Armstrong, K. (2007). A checklist of the vascular plants of Lao PDR: 1-394. Royal Botanic Gardens, Edinburgh.
    • Clayton, W.D., Harman, K.T. & Williamson, H. (2006). World Grass Species - Synonymy database The Board of Trustees of the Royal Botanic Gardens, Kew.
    • Henty, E.E. (1969). A manual of the grasses of New Guinea: 1-215. Division of Botany, Dpt. of Forests, LAE, New Guinea.

    Literature

    Kew Backbone Distributions
    • Newman, M., Ketphanh, S., Svengsuksa, B., Thomas, P., Sengdala, K., Lamxay, V. & Armstrong, K. (2007). A checklist of the vascular plants of Lao PDR: 1-394. Royal Botanic Gardens, Edinburgh.
    • Henty, E.E. (1969). A manual of the grasses of New Guinea: 1-215. Division of Botany, Dpt. of Forests, LAE, New Guinea.
    • Camus, E.G. & Camus, A. in H. Lecomte (1922). Flore Générale de l'indo-Chine 1(3): 193-336.

    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.
    Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/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