Poaceae
Eragrostis

Eragrostis rojasii Hack.

First published in Repert. Spec. Nov. Regni Veg. 7: 373 (1909)
This species is accepted
The native range of this species is Brazil to NE. Argentina. It is a perennial and grows primarily in the subtropical biome.

Descriptions

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

Morphology General Habit
Perennial; caespitose. Basal innovations intravaginal. Culms erect; 40-65 cm long; 1-4 -noded. Leaves mostly basal. Leaf-sheaths 5-20 cm long; longer than adjacent culm internode; hirsute. Ligule a fringe of hairs; 0.2-0.5 mm long. Leaf-blades flat, or involute; 10-30 cm long; 1.5-3 mm wide. Leaf-blade surface scabrous; glabrous; hairless except near base. Leaf-blade apex acuminate.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle; embraced at base by subtending leaf. Panicle open; obovate; 20-50 cm long. Primary panicle branches appressed, or ascending; 10-20 cm long. Panicle branches capillary; scabrous; bearded in axils. Spikelets solitary. Fertile spikelets pedicelled. Pedicels scabrous.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 3-7 fertile florets; with diminished florets at the apex. Spikelets linear, or lanceolate; laterally compressed; 4-8 mm long; 1.2-3 mm wide; breaking up at maturity; rhachilla persistent; retaining paleas. Rhachilla internodes eventually visible between lemmas.
Fertile
Spikelets comprising 3-7 fertile florets; with diminished florets at the apex. Spikelets linear, or lanceolate; laterally compressed; 4-8 mm long; 1.2-3 mm wide; breaking up at maturity; rhachilla persistent; retaining paleas. Rhachilla internodes eventually visible between lemmas.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes deciduous; similar; shorter than spikelet. Lower glume lanceolate; 2.5-4 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 2.7-4 mm long; 0.9 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex acuminate.
Morphology Reproductive morphology Flowers Florets
Fertile lemma ovate; 3.1-4.5 mm long; membranous; keeled; 3 -veined. Lemma midvein scabrous. Lemma lateral veins obscure. Lemma apex acute. Palea keels scabrous; adorned above. Apical sterile florets resembling fertile though underdeveloped.
Morphology Reproductive morphology Flowers
Lodicules 2; cuneate; fleshy. Anthers 3; 0.6-0.8 mm long.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp; ovoid; sulcate on hilar side; 1-1.1 mm long; light brown; reticulate.
Distribution
South America: Brazil and southern South America.
Reference
Eragrostideae. Boech & Valls 1995.
[GB]

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0

  • 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

  • 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 2026. 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 2026. 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