Pappostipa ameghinoi (Speg.) Romasch.

First published in J. Bot. Res. Inst. Texas 2: 184 (2008)
This species is accepted
The native range of this species is W. Argentina. It is a perennial and grows primarily in the temperate biome.

Descriptions

Morphology General Habit
Perennial; caespitose. Butt sheaths purple. Culms erect; 10-25 cm long; 0.5-0.7 mm diam.; 2-3 -noded. Culm-internodes smooth; distally glabrous, or pubescent. Culm-nodes constricted; glabrous. Leaf-sheaths mostly shorter than adjacent culm internode; smooth; glabrous on surface. Leaf-sheath oral hairs lacking, or pubescent. Ligule a ciliolate membrane; 1 mm long. Leaf-blades straight, or curved; conduplicate; 2-8 cm long; 0.4-0.7 mm wide. Leaf-blade surface smooth; glabrous. Leaf-blade apex pungent.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle; comprising 6-10 fertile spikelets; embraced at base by subtending leaf. Panicle open; oblong; 3-5 cm long; 1-1.5 cm wide; bearing few spikelets. Spikelets solitary. Fertile spikelets pedicelled. Pedicels 3-5 mm long; ciliate; hairy above.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 17-24 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; curved; pubescent; pungent.
Fertile
Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 17-24 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; curved; pubescent; pungent.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 17-24 mm long; 1.05 length of upper glume; membranous; without keels; 3 -veined. Lower glume apex acuminate. Upper glume lanceolate; 16-23 mm long; membranous; without keels; 3 -veined. Upper glume apex acuminate.
Morphology Reproductive morphology Flowers Florets
Fertile lemma lanceolate; subterete; 7-7.5 mm long; coriaceous; without keel; 5 -veined. Lemma surface pilose; hairy below. Lemma margins convolute; covering most of palea. Lemma hairs 1-3 mm long. Lemma apex dentate; 2 -fid; with lobes 1 mm long; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 25-35 mm long overall; with twisted column. Column of lemma awn 9-12 mm long; plumose. Palea 5-5.5 mm long; 2 -veined; without keels. Palea surface pilose.
Morphology Reproductive morphology Flowers
Lodicules 3. Anthers 3; yellow; anther tip smooth. Stigmas 2. Styles free to the base. Ovary glabrous.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp; fusiform. Hilum linear.
Distribution
South America: southern South America.
Reference
Stipeae. Fl Pat 1995.
[GB]

Sources

  • 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 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 2023. 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