Podostemaceae

Sphaerothylax Bisch. ex C.Krauss

First published in Flora 27: 426 (1844)
This genus is accepted
The native range of this genus is Cameroon to Ethiopia and S. Africa, Madagascar.

Descriptions

Podostemaceae, H. J. Beentje, M.Sc., Ph.D., F.L.S.. Flora of Tropical East Africa. 2005

Morphology General Habit
Perennial herbs, submerged freshwater aquatics; thalloid base attached to substrate, foliaceous and lobed or ribbon-like and branched; stems absent or very short, to elongate and branched with leaves and flowers congested at the nodes
Morphology Leaves
Leaves dissected into filiform segments
Morphology Reproductive morphology Inflorescences
Spathellas ± sessile on the thalloid part or in clusters axillary to leaves on elongated stems, solitary or aggregated, subtended by 2 scale-like bracts, surrounding the reflexed flower bud until anthesis, when the flower breaks the spathella and the pedicel becomes exserted, with an erect flower
Morphology Reproductive morphology Flowers
Flower with 2 tepals, these minute and subulate; stamen 1; ovary 1-locular, subspherical, with 2 subulate stigmas
Morphology Reproductive morphology Fruits
Capsule subspherical, 8-ribbed, dehiscing into 2 equal or slightly unequal valves, the smaller one caducous; seeds many, black, flattened and ovoid.
[FTEA]

Podostemaceae, C. Cusset. Flora Zambesiaca 9:2. 1997

Morphology General Habit
Submerged freshwater herbs; basal thalloid part firmly appressed and attached to substrate, foliaceous and ± deeply lobed or ribbon-like and branched.
Morphology Stem
Stems absent or very short and hardly emerging from the thallus, or elongate and branched.
Morphology Leaves
Leaves floating and repeatedly forked into ± filamentous segments.
Morphology Reproductive morphology Inflorescences
Pedicel long-exserted from the spathella after anthesis, bearing the flower erect. Spathellas (spathaceous bracts with enclosed flower) solitary or aggregated, ± sessile on the thalloid part, and in clusters in the axils of leaves on the elongated stems, subtended by 2 scale-like bracts, spherical to obovoid, dehiscing irregularly at the apex, or laterally; the flower inverted (reflexed) within the unruptured spathella before anthesis.
Morphology Reproductive morphology Flowers Tepal
Tepals 2, minute, subulate, one on each side of the andropodium.
Morphology Reproductive morphology Flowers Androecium Stamens
Stamen 1.Pollen 2-cellular.
Morphology Reproductive morphology Flowers Gynoecium Pistil
Ovary 1-locular, subspherical, with central placentation; placentas subglobose bearing numerous anatropous ovules; styles 2, subulate.
Morphology Reproductive morphology Fruits
Capsule subspherical, 8-ribbed, dehiscing into 2 slightly unequal valves, the smaller caducous.
Morphology Reproductive morphology Seeds
Seeds black, numerous, flattened ovate.
[FZ]

Sources

  • 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

  • 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