Orchidaceae
Disa

Disa zombica N.E.Br.

First published in D.Oliver & auct. suc. (eds.), Fl. Trop. Afr. 7: 278 (1898)
This species is accepted
The native range of this species is Tanzania to S. Tropical Africa. It is a tuberous geophyte and grows primarily in the seasonally dry tropical biome.

Descriptions

Orchidaceae, V. S. Summerhayes. Flora of Tropical East Africa. 1968

Morphology General Habit
A terrestrial herb 2.5–5.5 dm. high, glabrous except for the roots.
Vegetative Multiplication Tubers
Tubers elongate-ellipsoid or elongate-ovoid, 2–6 cm. long, 1–2 cm. in diameter, ± densely but shortly tomentose.
Morphology Roots
Roots slender, flexuous, pubescent.
Morphology Stem
Flowering stems erect, rather stout, almost entirely covered by sheathing leaves, terete; leaves 9–13, the lowermost short, sheath-like, red-spotted, the remainder adpressed to the stem, lanceolate, acute, the largest 5–12 cm. long, 1–2 cm. broad, the uppermost similar to the bracts. Sterile stems to 11 cm. long, with several overlapping red-spotted sheaths in the lower part and 1–3 leaves at the apex; leaves narrowly lanceolate, acute, 12–25 cm. long, 1–2 cm. broad.
Morphology Reproductive morphology Inflorescences
Inflorescence 9–16 cm. long, 4–6 cm. in diameter, densely 12–30-flowered.
Morphology Reproductive morphology Inflorescences Bracts
Bracts leafy, lanceolate, acuminate, 2.5–6 cm. long, mostly longer than the flowers.
Morphology Reproductive morphology Flowers
Flowers suberect, greenish-yellow or flesh-coloured, spotted or streaked with purple, the petals and lip ± magenta, malodorous; pedicel with ovary straight, 1.5–2 cm. long.
Morphology Reproductive morphology Flowers Calyx
Dorsal sepal erect, with a narrower lower part 6–10 mm. long and a broadly ovate or elliptical blade which is spurred in the middle, altogether 14–18 mm. long, the blade ± 7 mm. broad, the spur pendent, 5–7 mm. long, slightly swollen in the distal part; laterals spreading upwards, obliquely oblong, obtuse or rounded, ± the same length as the dorsal, 5–7 mm. broad.
Morphology Reproductive morphology Flowers Corolla
Petals erect, spathulate or oblanceolate with a broad ear-like basal part ± 5 mm. long and 4 mm. broad, total length 14–18 mm., 1.5–3.5 mm. broad towards the apex.
Morphology Reproductive morphology Flowers Labellum
Lip pendulous, linear, 13–16 mm. long, 1–2 mm. broad.
Morphology Reproductive morphology Flowers Androecium Stamens Anthers
Anther erect, 6 mm. high, shortly stalked.
Morphology Reproductive morphology Flowers Gynoecium Stigma
Stigma almost orbicular, 3 mm. in diameter.
Habitat
Upland grassland; 1000–2100 m.
Distribution
T4 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]

Orchidaceae, I. la Croix and P.J. Cribb. Flora Zambesiaca 11:1. 1995

Morphology General Habit
Terrestrial herb with separate fertile and sterile shoots.
Morphology General Shoots
Sterile shoot up to 6 cm long; leaves 2–3, conduplicate, erect, 6–20 × 8–20 cm, linear-elliptic, acute or apiculate. Fertile shoot 20–60 cm tall; cauline leaves imbricate, 4–6(13) cm long, ovate-lanceolate, acute, sheathing with the apical half often free; basal leaves shorter, red-spotted or barred.
Sterile
Sterile shoot up to 6 cm long; leaves 2–3, conduplicate, erect, 6–20 × 8–20 cm, linear-elliptic, acute or apiculate.
Fertile
Fertile shoot 20–60 cm tall; cauline leaves imbricate, 4–6(13) cm long, ovate-lanceolate, acute, sheathing with the apical half often free; basal leaves shorter, red-spotted or barred.
Morphology Reproductive morphology Inflorescences
Inflorescence usually dense, 9–16 cm long, 10–25-flowered.
Morphology Reproductive morphology Inflorescences Bracts
Floral bracts 3.5–4.5 cm long, lanceolate-ovate, acute to acuminate, much overtopping the flowers.
Morphology Reproductive morphology Flowers
Flowers with grey-green lateral sepals and magenta to purple petals and dorsal sepal.
Morphology Reproductive morphology Flowers Calyx
Dorsal sepal 14–21 mm long, spathulate; claw 7–11 mm long and c. 3 mm wide, erect, canaliculate; blade 7–11 × 5–10 mm, ovate, obtuse, galeate, ± facing down. Lateral sepals 14–18 mm long, obliquelyoblong, subacute.
Morphology Reproductive morphology Flowers Spur
Spur pendent from a small hump near the base of the blade, not reaching the base of the dorsal sepal, 4–7 mm long, subclavate to clavate.
Morphology Reproductive morphology Flowers Corolla
Petals 2-lobed; anterior lobe 4–7 × 3–5 mm, ovate, flanking the anther, spreading; posterior lobes 12–18 × 2–3 mm, oblanceolate, acute to subacute, erect inside the galea, the lobes partially overlapping.
Morphology Reproductive morphology Flowers Labellum
Lip pendent, 13–17 mm long, linear.
Morphology Reproductive morphology Flowers Rostellum
Rostellum c. 3 mm tall.
Morphology Reproductive morphology Flowers Androecium Stamens Anthers
Anther erect, 4–5 mm long.
Morphology Reproductive morphology Flowers Gynoecium Ovary
Ovary 1–1.5 cm long.
[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

    • '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 2025. 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 2025. 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