Lamiaceae
Haumaniastrum

Haumaniastrum venosum (Baker) Agnew

First published in Upland Kenya Wild Fl.: 643 (1974)
This species is accepted
The native range of this species is Uganda to S. Tropical Africa. It is a perennial and grows primarily in the seasonally dry tropical biome.

Descriptions

Lamiaceae (Labiatae), A.J. Paton, G. Bramley, O. Ryding, R.M. Polhill, Y.B. Harvey, M. Iwarsson, F. Willis, P.B. Phillipson, K. Balkwill, C.W. Lukhoba, D.F. Otieno, & R.M. Harley. Flora of Tropical East Africa. 2009

Type
Types: Malawi, Shire Highlands, Manganja Hills, Buchanan 266 (K!, syn.) & North Malawi [Nyassaland], Whyte s.n. (K!, syn.)
Morphology General Habit
Perennial herb or woody herb with 1–few stems arising from a woody rootstock, 0.6–1.5 m tall, faintly aromatic
Morphology Stem
Stems erect or ascending, quadrangular, branched or simple above, sometimes with adventitious roots near base, villose or densely villose with hairs patent, antrorse or both
Morphology Leaves
Leaves erect, appressed to stem below, spreading above, sessile; blades lanceolate, oblong or narrowly elliptic, 2–10 × 0.3–1.5 cm, entire or with few serrations, apex acute, base truncate, rounded or broadly cuneate, clasping stem, pubescent or densely so and with sessile glands; veins soon parallel with midrib or diverging, only becoming parallel with midrib distally; upper leaves subtending heads narrowly ovate or elliptic, grading into leaves below, sometimes apiculate at apex, uncoloured or blue or purplish, sometimes marked white
Morphology Reproductive morphology Inflorescences
Heads 5–14(–17) mm long, 5–10 mm in diameter, arranged in a corymb; verticils 6-flowered; bracts ovate, each subtending a 3-flowered cyme
Morphology Reproductive morphology Flowers Calyx
Flowering calyx 1.5 mm long, villose, sometimes purplish; fruiting calyx 3–4 mm long, distally villose; apex of posterior lip rounded, truncate or shallowly 3-lobed; anterior lip slightly longer than posterior, apex truncate to bifid
Morphology Reproductive morphology Flowers Corolla
Corolla dark purple or blue, 4.5–5.5 mm long; tube 3–5 mm long; posterior lip 4-lobed with median lobes small, sparsely pubescent with sessile glands
Morphology Reproductive morphology Fruits
Nutlets brown, 1–1.5 mm long, producing a small amount of mucilage when wet
Figures
Fig 34: 1–2, p 212
Ecology
Grassland, woodland, in wet areas; 250–1600 m
Conservation
Least concern; widespread
Note
This species is most similar to H. uniflorum A.J. Paton below. H. venosum may also be confused with H. bianense A.J. Paton from the Katanga which has similar appressed, clasping leaves but that species has a basal rosette of leaves or persistent leaf-bases and a more densely lanate indumentum.
Distribution
Range: Congo-Kinshasa, Zambia, Malawi, Mozambique, Zimbabwe Flora districts: U2 U4 K5 T1 T4 T6 T7 T8
[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]

J. R. Timberlake, E. S. Martins (2013). Flora Zambesiaca, Vol 8: part 8. Royal Botanic Gardens, Kew

Type
Types: Malawi, Shire Highlands, Manganja Hills, 1891, Buchanan 266 (K syntype); N Malawi (Nyasaland), n.d., Whyte s.n. (K syntype).
Morphology General Habit
Perennial herb or woody herb with 1 to few stem arising from a woody rootstock, 0.6–1.5 m tall; faintly aromatic- Stems erect or ascending, quadrangular, branched or simple above, sometimes with adventitious roots near base, villose or densely villose with hairs spreading, antrorse or both
Morphology Leaves
Leaves erect, adpressed to stem below, spreading above, sessile; blade 20–100 × 3–15 mm, lanceolate, oblong or narrowly elliptic, entire or with few serrations, apex acute, base truncate, rounded or broadly cuneate, clasping stem, pubescent or densely so, with sessile glands; veins soon parallel with midrib or diverging, only becoming parallel with midrib distally; upper leaf subtending heads narrowly ovate or elliptic, grading into leaf below, sometimes apiculate at apex, uncoloured or blue or purplish, sometimes marked white
Morphology Reproductive morphology Flowers
Heads 5–14(17) × 5–10 mm, arranged in a corymb; verticils 6-flowered; bract ovate, each subtending a 3-flowered cyme
Morphology Reproductive morphology Flowers Calyx
Calyx 1.5 mm long at anthesis, villose, sometimes purplish Fruiting calyx 3–4 mm long, distally villose; apex of posterior lip rounded, truncate or shallowly 3-lobed; anterior lip slightly longer than posterior, apex truncate to bifid
Morphology Reproductive morphology Flowers Corolla
Corolla dark purple or blue, 4.5–5.5 mm long; tube 3–5 mm long; posterior lip 4-lobed with median lobes small, sparsely pubescent with sessile glands
Morphology Reproductive morphology Fruits
Nutlets brown, 1–1.5 mm long, producing a small amount of mucilage when wet.
Distribution
Zambia, Zimbabwe, Malawi, Mozambique. Also in Congo (Katanga), Uganda, Kenya and Tanzania.
Ecology
Grassland and miombo woodland, in wet areas; 250–1800 m.
Conservation
Widespread: Least Concern.
Recognition
Haumaniastrum venosum may be confused with H. bianense A.J. Paton from southern Congo which has similar adpressed, clasping leaves, but that species has a basal rosette of leaves or persistent leaf-bases and a more densely lanate indumentum. H. venosum and H. bianense do not overlap in distribution.
[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

  • Flora of Tropical East Africa

    • Flora of Tropical East Africa
    • 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 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