Poaceae
Hyparrhenia

Hyparrhenia coleotricha (Steud.) Andersson ex Clayton

First published in Kew Bull., Addit. Ser. 2: 136 (1969)
This species is accepted
The native range of this species is Eritrea to Tanzania, Yemen. It is an annual and grows primarily in the desert or dry shrubland biome.

Descriptions

Gramineae, W. D. Clayton, S. M. Phillips & S. A. Renvoize. Flora of Tropical East Africa. 1974

Morphology General Habit
Annual; culms 1–2.5 m. high, supported by stilt roots.
Morphology Leaves
Leaf-blades up to 30 cm. long, 17 mm. wide.
Morphology Reproductive morphology Inflorescences
False panicle narrow, loose, 20–30 cm. long; spatheoles narrowly lanceolate, 4.5–7 cm. long, the peduncle from half to nearly as long and pilose with white hairs near the top; racemes 2–2.5 cm. long, 4–8-awned per pair, deflexed; raceme-bases subequal, the upper ± 1.5 mm. long, flattened, stiffly setose above, the tip produced into a scarious linear-oblong appendage 1.5–2 mm. long (± 1 mm. in Tanzania). Homogamous pairs 1 at the base of the lower raceme only.
Morphology Reproductive morphology Inflorescences Spikelets
Sessile spikelet 6.5–8(–9.5 in Tanzania) mm. long, pallid, hispidulous to densely pubescent; callus ± 2 mm. long, pungent; awn 5–7.5 cm. long. Pedicelled spikelet glabrous to sparsely pubescent, with a slender awn 6–11 mm. long.
Sessile
Sessile spikelet 6.5–8(–9.5 in Tanzania) mm. long, pallid, hispidulous to densely pubescent; callus ± 2 mm. long, pungent; awn 5–7.5 cm. long.
Pedicelled
Pedicelled spikelet glabrous to sparsely pubescent, with a slender awn 6–11 mm. long.
Habitat
Deciduous bushland on hill slope; 900–1200 m.
Distribution
T1 T7
[FTEA]

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
Annual. Butt sheaths glabrous, or pilose. Culms erect; 100-250 cm long; with prop roots. Culm-nodes glabrous, or bearded (fulvously). Leaves cauline. Ligule an eciliate membrane; 2-4 mm long. Leaf-blades tapering towards sheath; 15-30 cm long; 7-15 mm wide. Leaf-blade surface glabrous.
Morphology Reproductive morphology Inflorescences
Synflorescence compound; paniculate; 20-30 cm long. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; embraced at base by subtending leaf. Spatheole lanceolate; 4.5-7 cm long; membranous; glabrous. Peduncle pilose above. Racemes 2; paired; deflexed; 2-2.5 cm long; bearing few fertile spikelets; bearing 4-7 fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes linear. Rhachis internode tip oblique; flat. Raceme-bases flattened; subequal; 0.5-1.5 mm long; stiffly setose; extended into an oblong appendage; with 1-2 mm long appendage. Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; flattened; ciliate; tip oblique; toothed (0.3-0.6mm).
Morphology Reproductive morphology Inflorescences Spikelets
Basal sterile spikelets well-developed; on lower raceme 2 in number; 0 in upper raceme; lanceolate; 10-12 mm long; larger than fertile. Basal sterile spikelet glumes glabrous, or pubescent; scabrous on margins; lower glume muticous, or awned (0-3mm). Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; dorsally compressed; 8-12 mm long; longer than fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; pubescent; acute; awned; one glume awned; with 6-8 mm long awn. Companion sterile spikelet lemmas 2; enclosed by glumes. Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 7-9 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 1.5-3 mm long; pubescent; base pungent; attached obliquely.
Sterile
Basal sterile spikelets well-developed; on lower raceme 2 in number; 0 in upper raceme; lanceolate; 10-12 mm long; larger than fertile. Basal sterile spikelet glumes glabrous, or pubescent; scabrous on margins; lower glume muticous, or awned (0-3mm). Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; dorsally compressed; 8-12 mm long; longer than fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; pubescent; acute; awned; one glume awned; with 6-8 mm long awn. Companion sterile spikelet lemmas 2; enclosed by glumes.
Fertile
Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 7-9 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 1.5-3 mm long; pubescent; 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; keel-less except near apex. Lower glume surface villous. Lower glume hairs white. Lower glume apex dentate; 2 -fid. Upper glume linear; coriaceous; without keels.
Morphology Reproductive morphology Flowers Florets
Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 1 length of fertile lemma; hyaline; 2 -veined. Fertile lemma linear; membranous; without keel; 1 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 50-70 mm long overall; with twisted column. Column of lemma awn pubescent. Palea absent or minute.
Morphology Reproductive morphology Flowers
Lodicules 2; cuneate; fleshy. Anthers 3. Stigmas 2.
Distribution
Africa: northeast tropical and east tropical. Asia-temperate: Arabia.
Reference
Andropogoneae. WDC.
Diagnostic
Peduncle hairs white.
[GB]

Sources

  • Angiosperm Extinction Risk Predictions v1

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

  • Flora of Tropical East Africa

    • Flora of Tropical East Africa
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • 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

    • 'The Herbarium Catalogue, Royal Botanic Gardens, Kew. Published on the Internet http://www.kew.org/herbcat [accessed on Day Month Year]'. Please enter the date on which you consulted the system.
    • 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