Poaceae
Hyparrhenia

Hyparrhenia coriacea Mazade

First published in Adansonia, n.s., 18: 147 (1978)
This species is accepted
The native range of this species is Central African Republic. It is an annual and grows primarily in the seasonally dry tropical biome.

Descriptions

Morphology General Habit
Annual. Culms erect; 250 cm long. Leaves cauline. Leaf-sheaths mostly shorter than adjacent culm internode; glabrous on surface. Leaf-sheath auricles erect. Ligule an eciliate membrane; 3 mm long. Leaf-blades 40-70 cm long; 7-14 mm wide. Leaf-blade surface glabrous, or puberulous; hairy abaxially.
Morphology Reproductive morphology Inflorescences
Synflorescence compound; paniculate. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; enclosed. Spatheole linear; 9 cm long; scarious; glabrous. Peduncle 2.5 cm long; pilose above. Racemes 2; paired; deflexed; bearing few fertile spikelets; bearing 1 fertile spikelets on each. Rhachis fragile at the nodes. Rhachis internodes linear. Rhachis internode tip oblique; flat. Raceme-bases flattened; subequal. Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; tip oblique.
Morphology Reproductive morphology Inflorescences Spikelets
Basal sterile spikelets well-developed; on lower raceme 4 in number; 4 in upper raceme; forming an involucre about the fertile; lanceolate; 13-17 mm long; equalling fertile. Basal sterile spikelet lower glume muticous. Companion sterile spikelets well-developed; lanceolate; dorsally compressed; separately deciduous. Companion sterile spikelet glumes chartaceous; acute. Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong, or oblanceolate; dorsally compressed; 10-15 mm long; 2 mm wide; falling entire; deciduous with accessory branch structures. Spikelet callus linear; 3.5-4.5 mm long; pilose; base pungent; attached obliquely.
Sterile
Basal sterile spikelets well-developed; on lower raceme 4 in number; 4 in upper raceme; forming an involucre about the fertile; lanceolate; 13-17 mm long; equalling fertile. Basal sterile spikelet lower glume muticous. Companion sterile spikelets well-developed; lanceolate; dorsally compressed; separately deciduous. Companion sterile spikelet glumes chartaceous; acute.
Fertile
Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong, or oblanceolate; dorsally compressed; 10-15 mm long; 2 mm wide; falling entire; deciduous with accessory branch structures. Spikelet callus linear; 3.5-4.5 mm long; pilose; base pungent; attached obliquely.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; without keels; 9-11 -veined. Lower glume surface pubescent. Lower glume hairs white; 1 mm long. Upper glume linear; coriaceous; without keels; 3 -veined. Upper glume primary vein scaberulous. Upper glume surface pubescent. Upper glume margins ciliolate. Upper glume apex acute.
Morphology Reproductive morphology Flowers Florets
Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; hyaline; 2 -veined; ciliolate on margins; dentate; 2 -fid. Fertile lemma linear; membranous; without keel. Lemma apex dentate; 2 -fid; with lobes 1-1.5 mm long; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 120-160 mm long overall; with twisted column. Column of lemma awn pubescent; with 1-1.2 mm long hairs. Palea 2-2.6 mm long.
Morphology Reproductive morphology Fruits
Caryopsis oblong; dorsally compressed; 6.5-7.5 mm long.
Distribution
Africa: west-central tropical.
Reference
Andropogoneae. Mazade 2005.
[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: threatened. Confidence: confident
[AERP]

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

  • 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