Poaceae
Hyparrhenia

Hyparrhenia wombaliensis (Vanderyst ex Robyns) Clayton

First published in Kew Bull., Addit. Ser. 2: 75 (1969)
This species is accepted
The native range of this species is W. Central Tropical Africa. It is a perennial and grows primarily in the wet tropical biome.

Descriptions

Morphology General Habit
Perennial; caespitose. Butt sheaths glabrous, or sparsely hairy. Culms erect; slender; 40-60 cm long. Leaves cauline. Ligule an eciliate membrane; 0.5-1 mm long. Leaf-blades filiform, or linear; flat, or convolute; 15-25 cm long; 1-1.5 mm wide. Leaf-blade surface glabrous, or hirsute; sparsely hairy; hairy abaxially.
Morphology Reproductive morphology Inflorescences
Synflorescence simple. Inflorescence composed of racemes; terminal; subtended by a spatheole; exserted. Spatheole linear; 4-10 cm long; membranous. Peduncle 8-10 cm long; glabrous. Racemes 2; paired; erect; 2-3 cm long; bearing 4-6 fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Rhachis hairs white. Rhachis internodes linear; 3.5-5 mm long. Rhachis internode tip oblique; flat. Raceme-bases filiform; unequal (the longer measured); 5-8 mm long; glabrous. 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.
Morphology Reproductive morphology Inflorescences Spikelets
Basal sterile spikelets well-developed; 2 in number (lower raceme); 0 in upper raceme; lanceolate; equalling fertile. Basal sterile spikelet glumes smooth on margins; lower glume muticous. Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; dorsally compressed; 5-6 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; glabrous; acute; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes. Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 5-6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 1 mm long; pubescent; base acute; attached obliquely.
Sterile
Basal sterile spikelets well-developed; 2 in number (lower raceme); 0 in upper raceme; lanceolate; equalling fertile. Basal sterile spikelet glumes smooth on margins; lower glume muticous. Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; dorsally compressed; 5-6 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; glabrous; acute; muticous. 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; 5-6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 1 mm long; pubescent; base acute; 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. Lower glume surface glabrous, or hispidulous. 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 entire; emarginate; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 8-15 mm long overall; with twisted column. Column of lemma awn pubescent; with 0.2-0.3 mm long hairs. Palea absent or minute.
Morphology Reproductive morphology Flowers
Lodicules 2; cuneate; fleshy. Anthers 3. Stigmas 2.
Distribution
Africa: west-central tropical.
Reference
Andropogoneae. WDC.
[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: low confidence
[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

  • 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 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