Polystachya isochiloides Summerh.

First published in Bull. Misc. Inform. Kew 1939: 498 (1939)
This species is accepted
The native range of this species is NE. & Central Tanzania. It is a pseudobulbous epiphyte and grows primarily in the seasonally dry tropical biome.

Descriptions

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/179365/1576444

Conservation
EN - endangered
[IUCN]

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]

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

Morphology General Habit
An erect epiphytic herb 10–38 cm. high.
Morphology Stem
Stems approximate, terete, with a basal nut-like swelling, up to 38 cm. high, 1–3 mm. in diameter, covered at the base by 1–2 scarious tubular sheaths, 3–5-leaved above.
Morphology Leaves
Leaves almost erect, linear or linear-ligulate, shortly obtuse or subacutely bidentate at apex, 4–17 cm. long, 2–6 mm. wide.
Morphology Reproductive morphology Inflorescences
Inflorescence subequal in length to the leaves, unbranched or weakly branched, to 17 cm. long, 4–many-flowered; peduncle to 12 cm. long, covered with papery sheaths; rhachis densely pubescent; bracts lanceolate or rarely ovate, long- acuminate, 1.5–7 mm. long; pedicel and ovary 5–7 mm. long, glabrous to pubescent.
Morphology Reproductive morphology Flowers
Flowers cream-coloured, fragrant, up-turned, drying yellow or brown.
Morphology Reproductive morphology Flowers Calyx
Dorsal sepal convex, lanceolate, acute, 8–10 mm. long, 2.5–3 mm. wide; lateral sepals subfalcate, triangular-lanceolate, acute, 10 mm. long, 4–5 mm. wide; mentum conical, 3.5–4.5 mm. high; sepals glabrous or very sparsely hairy.
Morphology Reproductive morphology Flowers Corolla
Petals curved, ligulate- oblanceolate, 7–9 mm. long, 1.7–2 mm. wide, acute or slightly acuminate.
Morphology Reproductive morphology Flowers Labellum
Lip shortly clawed, 3-lobed in middle, 3.5–9.5 mm. long, 6–6.5 mm. wide, recurved; side lobes semi-orbicular, rounded, 1 mm. long, 2 mm. wide; mid-lobe ovate-lanceolate to broadly oblong-lanceolate, 4 mm. long, 2.75 mm. wide, strongly recurved, acute or acuminate, margin crisped-undulate.
Morphology Reproductive morphology Flowers Column
Column slightly incurved, 2 mm. long, semi-terete.
Figures
Fig. 79, p. 378.
Habitat
Epiphytic on forest margins; 800–1400 m.
Distribution
T3 T6
[FTEA]

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
  • Herbarium Catalogue Specimens

    • Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/
  • IUCN Categories

    • IUCN Red List of Threatened Species
    • http://creativecommons.org/licenses/by-nc-sa/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