Skip to main content Skip to main navigation menu Skip to site footer
Responsive image
Issue: Vol. 619 No. 1: 5 Oct. 2023
Type: Article
Published: 2023-10-05
DOI: 10.11646/phytotaxa.619.1.8
Page range: 117-122
Abstract views: 86
PDF downloaded: 9

Exochaenium natalense (Gentianaceae), a reinstated taxon endemic to KwaZulu-Natal, South Africa

Institute of Biology; University of Neuchâtel; Rue Emile-Argand 11; 2000 Neuchâtel; Switzerland
Custodians of Rare and Endangered Wildflowers (CREW) Programme; South African National Biodiversity Institute; South Africa
Custodians of Rare and Endangered Wildflowers (CREW) Programme; South African National Biodiversity Institute; South Africa
Bews Herbarium; Centre for Functional Biodiversity; School of Life Sciences; University of KwaZulu-Natal; Pietermaritzburg; South Africa
Eudicots KwaZulu-Natal Pondoland South africa summer rainfall region taxonomy

Abstract

Based on morphological and ecological considerations, Belmontia natalensis (syn. Exochaenium grande var. homostylum) is reinstated as Exochaenium natalense (Gentianaceae). It only occurs in a section of the coastal region of the Eastern Cape (Pondoland) and southern KwaZulu-Natal provinces, South Africa. Exochaenium natalense differs from E. grande, the only other South African Exochaenium taxon, by having smaller flowers (corolla diameter < 2 cm vs > 3 cm) with a different colour (white vs cream-salmon or yellow). Because the type material of E. natalense consists of two sheets, a lectotype is designated.

 

References

  1. Grisebach, A.H.R. (1845) Gentianaceae. In: Candolle, A. de (Ed.) Prodromus systematis naturalis regni vegetabilis, vol. 9. Fortin, Masson et Sociorum, Paris, pp. 39–141. [https://www.biodiversitylibrary.org/item/247794#page/43/mode/1up]
  2. Hill, A.W. (1908) Notes on Sebaea and Exochaenium. Bulletin of Miscellaneous Information (Royal Gardens, Kew) 1908: 317–341. https://doi.org/10.2307/4111714
  3. Hill, A.W. & Prain, D. (1909) Gentianaceae. In: Thiselton-Dyer, W.T. (Ed.) Flora Capensis. Vol. IV, Section 1. Lovell Reeve & Co. LTD, London, pp. 1056–1121. [https://www.biodiversitylibrary.org/item/15242#page/1070/mode/1up]
  4. Kissling, J. (2012) Taxonomy of Exochaenium and Lagenias: two resurrected genera of tribe Exaceae (Gentianaceae). Systematic Botany 37 (1): 238–253. https://doi.org/10.1600/036364412X616800
  5. Kissling, J. (2015) Exochaenium clavatum subsp. stella-pallustre (Gentianaceae—Exaceae), a new subspecies from Zambia. Phytotaxa 203 (3): 297–300. https://doi.org/10.11646/phytotaxa.203.3.10
  6. Kissling, J. & Barrett, S.C.H. (2013) Variation and evolution of herkogamy in Exochaenium (Gentianaceae): implication for the evolution of distyly. Annals of Botany 112 (1): 95–102. https://doi.org/10.1093/aob/mct097
  7. Kissling, J., Yuan, Y.-M., Küpfer, P. & Mansion, G. (2009) The polyphyletic genus Sebaea (Gentianaceae): A step forward in understanding the morphological and karyological evolution of the Exaceae. Molecular Phylogenetics and Evolution 53 (3): 734–748. https://doi.org/10.1016/j.ympev.2009.07.025
  8. Linnaeus, C. (1753) Species Plantarum. Vol. 1. Holmiae, Impensis Laurentii Salvii, pp. 135, 142, 271. https://doi.org/10.5962/bhl.title.669
  9. Marais, W. & Verdoorn, I.C. (1963) Gentianaceae. In: Dyer, R.A., Codd, L.E. & Rycroft, H.B. (Eds.) Flora of Southern Africa. Vol. 26. Government Printer, Pretoria, pp. 172–211.
  10. Meyer, E.H.F. (1837) Commentariorum de plantis Africae Australioris. Vol. 1, fascic. 2. Leopold Voss, Leipzig, 326 pp. https://doi.org/10.5962/bhl.title.50
  11. Mucina, L. & Rutherford, M.L. (2006) The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria, pp. 1–816.
  12. Schinz, H. (1894) Beitraege zur Kenntnis der Afrikanischen Flora. Bulletin de l’Herbier Boissier 2: 180–228. [https://www.biodiversitylibrary.org/item/105264#page/200/mode/1up]
  13. Schinz, H. (1896) Gentianaceae. Bulletin de l’Herbier Boissier 4: 442–444. [https://www.biodiversitylibrary.org/item/104951#page/476/mode/1up]
  14. Schinz, H. (1906) Gentianaceae. Bulletin de l’Herbier Boissier, Sér. 2, 6: 714–746. [https://www.biodiversitylibrary.org/item/105785#page/794/mode/1up]
  15. Theirs, B. (2022 [continuously updated]) Index Herbariorum: A global Directory of Public Herbaria and Associated Staff. New York Botanical Garden’s Virtual Herbarium. Available from: http://sweetgum.nybg.org/science/ih/ (Accessed 15 August 2022).
  16. Turland, N.J., Wiersema, J.H., Barrie, F.R., Greuter, W., Hawksworth, D.L., Herendeen, P.S., Knapp, S., Kusber, W.-H., Li, D.-Z., Marhold, K., May, T.W., McNeill, J., Monro, A.M., Prado, J., Price, M.J. & Smith, G.F. (Eds.) (2018) International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017. Regnum Vegetabile 159. Koeltz Botanical Books, Glashütten. https://doi.org/10.12705/Code.2018
  17. Wolfe, L.M., Massinga, P.H. & Johnson, S.D. (2009) A quantitative evaluation of the distylous syndrome in Sebaea grandis (Gentianaceae). South African Journal of Botany 75 (4): 785–790. https://doi.org/10.1016/j.sajb.2009.07.014