Poaceae
Anthoxanthum

Anthoxanthum mexicanum (Rupr. ex E.Fourn.) Mez

First published in Repert. Spec. Nov. Regni Veg. 17: 291 (1921)
This species is accepted
The native range of this species is Mexico (Puebla, Oaxaca, Chiapas) to Guatemala, Venezuela. It is a perennial and grows primarily in the montane tropical 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. Culms geniculately ascending; 40-70 cm long. Lateral branches lacking. Ligule an eciliate membrane. Leaf-blades 5-15 cm long; 2-4 mm wide. Leaf-blade apex abruptly acute.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle. Panicle contracted; linear, or lanceolate; interrupted; 6-12 cm long. Spikelets solitary. Fertile spikelets pedicelled. Pedicels ciliate.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 5-6 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes elongated below proximal fertile floret. Rhachilla elongation 0.2 mm long.
Fertile
Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 5-6 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes elongated below proximal fertile floret. Rhachilla elongation 0.2 mm long.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes persistent; dissimilar; exceeding apex of florets; thinner than fertile lemma. Lower glume ovate; 3.5-4 mm long; 0.66 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume oblong; 5-6 mm long; 2 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume surface asperulous. Upper glume apex acute.
Morphology Reproductive morphology Flowers Florets
Basal sterile florets dissimilar; barren; without significant palea; attached to and deciduous with the fertile. Lemma of lower sterile floret oblong; 5 mm long; chartaceous; without keels; 5 -veined; pubescent; bearing tawny hairs; dentate; 2 -fid; obtuse; awned. Awn of lower sterile floret dorsal; arising 0.75 way up back of lemma; 1-1.5 mm long. Lemma of upper sterile floret oblong; 5 mm long; chartaceous; pubescent; dentate; 2 -fid; obtuse; awned. Awn of upper sterile floret dorsal; arising 0.25 way up back of lemma; geniculate; 6-7 mm long. Fertile lemma oblong; 2.5 mm long; cartilaginous; without keel; 5 -veined. Lemma lateral veins obscure. Lemma margins convolute; covering most of palea. Lemma apex obtuse. Palea oblong; 1 -veined; without keels.
Morphology Reproductive morphology Flowers
Lodicules absent. Anthers 2. Stigmas 2; protogynous; pubescent.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp. Hilum punctiform.
Distribution
North America: Mexico. South America: Mesoamericana and northern South America.
Reference
Aveneae. WDC 1994.
[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