Psathyrostachys fragilis (Boiss.) Nevski

First published in V.L.Komarov (ed.), Fl. URSS 2: 716 (1934)
This species is accepted
The native range of this species is Türkiye to Afghanistan, Mongolia. It is a perennial and grows primarily in the temperate biome.

Descriptions

Morphology General Habit
Perennial; caespitose. Rhizomes short. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Culms 30-60 cm long. Ligule an eciliate membrane. Leaf-blades convolute; 15-30 cm long; 1-2 mm wide; glaucous.
Morphology Reproductive morphology Inflorescences
Inflorescence composed of racemes. Racemes 1; single; bilateral; 7-9 cm long. Rhachis fragile at the nodes. Spikelet packing broadside to rhachis. Rhachis internodes linear; 4-5 mm long; falling with spikelet above. Spikelets ascending; in threes. Fertile spikelets sessile; 3 in the cluster; all alike.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 1 fertile florets; with diminished florets at the apex. Spikelets lanceolate; dorsally compressed; 10-13 mm long; falling entire; deciduous with accessory branch structures.
Fertile
Spikelets comprising 1 fertile florets; with diminished florets at the apex. Spikelets lanceolate; dorsally compressed; 10-13 mm long; falling entire; deciduous with accessory branch structures.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes collateral; similar; exceeding apex of florets; gaping. Lower glume subulate; 35-55 mm long; 1 length of upper glume. Lower glume surface scabrous. Upper glume subulate; 35-55 mm long. Upper glume surface scabrous.
Morphology Reproductive morphology Flowers Florets
Fertile lemma lanceolate; 10-13 mm long; coriaceous; without keel; 7 -veined. Lemma surface scabrous; rough above. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn curved; spreading; 40-55 mm long overall. Palea coriaceous. Palea keels scabrous. Apical sterile florets 1 in number; barren; linear.
Morphology Reproductive morphology Flowers
Ovary beaked; pubescent on apex.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp. Hilum linear; 1 length of caryopsis.
Distribution
Asia-temperate: Caucasus and western Asia.
Reference
Triticeae. Fl Iraq.
[GB]

Morphology General Habit
Perennial; caespitose; clumped densely. Butt sheaths glabrous. Culms 45-60 cm long; 2 mm diam. Culm-internodes distally pubescent. Culm-nodes glabrous. Ligule an eciliate membrane. Leaf-blades convolute; 15-30 cm long; 0.5-1.2 mm wide; glaucous. Leaf-blade surface scabrous.
Morphology Reproductive morphology Inflorescences
Inflorescence composed of racemes. Peduncle pubescent above. Racemes 1; single; bilateral; 5-8 cm long; 23-48 mm wide. Rhachis fragile at the nodes; ciliate on margins. Spikelet packing broadside to rhachis. Rhachis internodes linear; falling with spikelet above. Spikelets in pairs, or in threes. Fertile spikelets sessile; 2-3 in the cluster; all alike.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 8-10 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pubescent. Spikelet callus hairs 1 mm long. Rhachilla internodes elongated below proximal fertile floret. Rhachilla elongation 0.5 mm long.
Fertile
Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 8-10 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pubescent. Spikelet callus hairs 1 mm long. Rhachilla internodes elongated below proximal fertile floret. Rhachilla elongation 0.5 mm long.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes collateral; similar; exceeding apex of florets; gaping. Lower glume subulate; 25-40 mm long; 1 length of upper glume. Upper glume subulate; 25-40 mm long.
Morphology Reproductive morphology Flowers Florets
Fertile lemma lanceolate; 8-10 mm long; 1.2-1.5 mm wide; coriaceous; without keel. Lemma surface pubescent; hairy above. Lemma margins ciliolate. Lemma hairs 0.7 mm long. Lemma apex lobed; 2 -fid; with lanceolate lobes; with lobes 2.5 mm long; acuminate; awned; 1 -awned. Principal lemma awn from a sinus; 20-30 mm long overall. Palea coriaceous.
Distribution
Asia-temperate: western Asia.
Reference
Triticeae. Ponert 2005.
[GB]

Sources

  • GrassBase - The Online World Grass Flora

    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • Herbarium Catalogue Specimens

    • 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 Vascular Plants 2022. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2022 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 2022. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2022 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Science Photographs

    • Copyright applied to individual images