Poaceae
Eragrostis

Eragrostis silveana Swallen

First published in Amer. J. Bot. 19: 438 (1932)
This species is accepted
The native range of this species is S. Texas to Mexico. It is a perennial and grows primarily in the desert or dry shrubland biome.

Descriptions

Morphology General Habit
Perennial; caespitose. Rhizomes short; knotty. Glands elongated. Culms erect, or geniculately ascending; 45-60 cm long. Culm-internodes glandular. Leaf-sheaths viscid; outer margin hairy. Ligule a fringe of hairs. Leaf-blades flat, or involute; 8-25 cm long; 2-4 mm wide; without exudate, or viscid. Leaf-blade apex attenuate.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle. Panicle open; ovate; 20-30 cm long; 10-15 cm wide. Primary panicle branches ascending, or spreading; 6-12 cm long. Panicle branches capillary; viscid; scabrous; bearded in axils. Spikelets solitary. Fertile spikelets pedicelled.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 4-9 fertile florets; with diminished florets at the apex. Spikelets linear, or oblong; laterally compressed; 3.5-5 mm long; 1 mm wide; breaking up at maturity; rhachilla deciduous; disarticulating below each fertile floret.
Fertile
Spikelets comprising 4-9 fertile florets; with diminished florets at the apex. Spikelets linear, or oblong; laterally compressed; 3.5-5 mm long; 1 mm wide; breaking up at maturity; rhachilla deciduous; disarticulating below each fertile floret.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes deciduous; similar; shorter than spikelet. Lower glume ovate; 1 mm long; 1 length of upper glume; chartaceous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 1-1.2 mm long; 0.7-0.8 length of adjacent fertile lemma; chartaceous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex acute.
Morphology Reproductive morphology Flowers Florets
Fertile lemma ovate; 1.4 mm long; 1 mm wide; chartaceous; purple; keeled; 3 -veined. Lemma lateral veins prominent. Lemma apex acute. Palea keels ciliate. Apical sterile florets resembling fertile though underdeveloped.
Morphology Reproductive morphology Flowers
Lodicules 2; cuneate; fleshy.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp; ellipsoid; 0.6 mm long.
Distribution
North America: south-central USA and Mexico.
Reference
Eragrostideae. Gr Texas 1994.
[GB]

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]

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/44392366/44520303

Conservation
LC - least concern
[IUCN]

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

  • IUCN Categories

    • IUCN Red List of Threatened Species
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. 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 2024. 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