Poaceae
Trisetaria

Trisetaria macrochaeta (Boiss.) Maire

First published in Bull. Soc. Hist. Nat. Afrique N. 33: 92 (1942)
This species is accepted
The native range of this species is W. Central Spain, Libya to Israel. It is an annual and grows primarily in the subtropical biome.

Descriptions

Morphology General Habit
Annual; culms solitary, or caespitose. Culms erect, or geniculately ascending; 10-22 cm long. Leaf-sheaths smooth, or scaberulous; glabrous on surface. Ligule an eciliate membrane; 0.5 mm long. Leaf-blades flat, or convolute; 4-8 cm long; 1-1.5 mm wide. Leaf-blade midrib conspicuous. Leaf-blade surface puberulous; hairy adaxially. Leaf-blade margins scabrous.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle. Panicle contracted; oblong, or ovate; 1-7 cm long; 0.5-3.5 cm wide. Primary panicle branches 0.5-3 cm long. Panicle axis scabrous. Panicle branches scabrous. Spikelets solitary. Fertile spikelets pedicelled. Pedicels scabrous.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 2 fertile florets; with a barren rhachilla extension. Spikelets cuneate; laterally compressed; 3.5-4 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes glabrous, or pubescent.
Fertile
Spikelets comprising 2 fertile florets; with a barren rhachilla extension. Spikelets cuneate; laterally compressed; 3.5-4 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes glabrous, or pubescent.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes persistent; dissimilar; exceeding apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume linear, or lanceolate; 2.5-3 mm long; 0.7-0.8 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex attenuate; muticous, or mucronate, or awned; 1 -awned. Lower glume awn 0.5 mm long. Upper glume ovate; 3.5-4 mm long; 1-1.25 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume apex entire, or dentate; 2 -fid; acuminate; muticous, or mucronate, or awned; 1 -awned. Upper glume awn 0.5 mm long.
Morphology Reproductive morphology Flowers Florets
Fertile lemma lanceolate; 3 mm long; membranous; shiny; without keel; 3 -veined. Lemma surface glabrous, or pubescent. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn dorsal; arising 0.6 way up back of lemma; geniculate; 5-7 mm long overall; with twisted column. Lateral lemma awns arising on apex of lobes; 1.5 mm long; shorter than principal. Palea gaping; linear; 0.66 length of lemma; hyaline. Palea keels scabrous. Palea apex dentate; 2 -fid.
Morphology Reproductive morphology Flowers
Anthers 3; 1 mm long. Ovary glabrous.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp. Hilum punctiform.
Distribution
Europe: southwestern. Africa: north. Asia-temperate: western Asia.
Reference
Aveneae. Fl Afr N 1993.
[GB]

Sources

  • 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

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2023. 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 2023. 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