Cyperaceae
Bulbostylis

Bulbostylis atracuminata (Larridon, Reynders & Goetgh.) Larridon & Roalson

First published in Phytotaxa 395: 204 (2019)
This species is accepted
The native range of this species is S. DR Congo to Zambia. It is an annual and grows primarily in the seasonally dry 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: threatened. Confidence: confident
[AERP]

J. Browning, K.D. Gordon-Gray†, M. Lock, H. Beentje, K. Vollesen, K. Bauters, C. Archer, I. Larridon, M. Xanthos, P. Vorster, J. Bruhl, K. Wilson and X. Zhang (2020). Flora Zambesiaca Volume: 14: Cyperaceae. M.Á. García, J.R. Timberlake (Eds). Kew Publish

Type
Zambia, Mporokoso Dist., Kasanshi dambo, 55 km ESE of Mporokoso, 13.vi.1962, Robinson 5166 (K holotype, MO).
Morphology General Habit
Annual herb growing in small tufts; culms to 50 cm; root system limited
Morphology Leaves
Leaves to 40 cm × c. 0.5 mm, basal, distichous, ± V-shaped to involute, eligulate; sheath orifice lacking typical bundle of hairs
Morphology Reproductive morphology Inflorescences
Inflorescence anthelate, with 1–2(5) spikelets
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets ovoid, relatively large and thick, with many nearly black, spirally arranged glumes
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes 1–3.5 × 0.5–2.5 mm, spathulate, shortly mucronate to 1.2 mm, distinctly fimbriate at tip
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens usually 3
Morphology Reproductive morphology Flowers Gynoecium Style
Style branches 2
Morphology Reproductive morphology Fruits
Nutlet lenticular, obovate, 1 × 0.6 mm, conspicuously smooth, shiny black, often apiculate.
Distribution
Zambia. Also in the southern D.R. Congo (Katanga).
Ecology
In temporarily wet areas (marshes, riverbanks), on shallow soils from humid woodland to edge of open forest; 1400– 1700 m.
Conservation
Widespread; not threatened.
Recognition
This species might be confused with some smaller annual specimens of Nemum angolense, which share an anthelate inflorescence type with nearly black spikelets; both species occur in D.R. Congo and Zambia. There are several distinguishing characters – the spikelets of N. atracuminatum are generally thicker and the glumes show remarkable differences, while the glumes of N. angolense are obovate, obtuse or somewhat acute, and often ciliate on the margin. Those of N. atracuminatum are conspicuously spatulate, mucronate and distinctly fimbriate at the tips.
[FZ]

Sources

  • Angiosperm Extinction Risk Predictions v1

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

  • Flora Zambesiaca

    • Flora Zambesiaca
    • 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