Vol. 79 No. 1 (2024)
Articles

Keetia nodulosa sp. nov. (Rubiaceae - Vanguerieae) of West-Central Africa: bacterial leaf nodulation discovered in a fourth genus and tribe of Rubiaceae

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  • Martin Cheek,
  • Jean Michel Onana
Martin Cheek
Herbarium, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AE
Jean Michel Onana
University of Yaoundé I, Faculty of Science, Department of Plant Biology P.O Box 812 Yaoundé
DOI: https://doi.org/10.36253/jopt-15946

Published 2024-03-19

Keywords

  • Bacterial leaf nodules,
  • Burkholderia,
  • cloud forest,
  • conservation,
  • horizontal transfer,
  • Paraburkholderia
    • ...More
    Less

How to Cite

Cheek, M., & Onana, J. M. (2024). Keetia nodulosa sp. nov. (Rubiaceae - Vanguerieae) of West-Central Africa: bacterial leaf nodulation discovered in a fourth genus and tribe of Rubiaceae. Webbia, 79(1), 31–46. https://doi.org/10.36253/jopt-15946

Copyright (c) 2024 Martin Cheek, Jean Michel Onana

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Abstract

Keetia nodulosa Cheek, a cloud forest climber nearly endemic to Cameroon, with a single record from Nigeria, is described and illustrated. It is remarkable as the first known species to be recorded with bacterial leaf nodules (BLN) in the genus Keetia, and also, in the tribe Vanguerieae. Other genera in Rubiaceae with BLN are Psychotria (Psychotrieae-Rubioideae), Sericanthe (Coffeeae) and Pavetta (Pavetteae), both Ixoroideae/Dialypetalanthoideae. The BLN in Keetia (Vanguerieae) are illustrated for the first time here. The characteristics and significance of bacterial leaf nodulation in Keetia nodulosa are discussed in the context of rapidly growing knowledge on the subject in flowering plants. Keetia nodulosa is provisionally assessed using the 2012 IUCN standard as Endangered (EN B2ab(iii)). The importance of its conservation, and options for achieving this are discussed in the context of recent extinctions of other plant species in Cameroon. This discovery of a new cloud forest species is discussed in relation to other cloud forest plant species described in the last twenty years which are also distributed over the highlands of the western half of Cameroon.

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