Abstract
Populations of plants from around Kleinmond in the Western Cape Province (South Africa), previously identified as Pelargonium setulosum, differ from typical populations of that species in ecology, distribution, and morphologically in the shape of the nectar guides, and appear to constitute a separate species. Field work was done, specimens were collected in the field, and material from four different herbaria were studied to record morphological variation. The Kleinmond populations previously included in P. setulosum are described as the new species P. pseudosetulosum. Morphological, ecological, and geographical evidence indicate that this species forms part of Pelargonium subg. Pelargonium sect. Pelargonium.
References
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<p>Ecklon, C.F. & Zeyher, C.L.P. (1835) <em>Enumeratio plantarum Africae australis extratropicae: quae collectae, determinatae et expositae. Sumtibus auctorum.</em> Prostat apud Perthes & Besser, Hamburgi, 144 pp.</p>
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<p>Knuth, R. (1912) Geraniaeeae. <em>In</em>: Engler, A. (Ed.) <em>Das Pflanzenreich</em> <em>IV.129</em>. Willhelm Engelmann, Leipzig, pp. 316–517. [https://www.biodiversitylibrary.org/bibliography/250#/summary]</p>
<p>Le Roux, M.M. (2019) A taxonomic revision of the southern African species of <em>Pelargonium</em> section <em>Peristera</em> (Geraniaceae). <em>Phytotaxa</em> 418 (2): 119–157. https://doi.org/10.11646/phytotaxa.418.2.1</p>
<p>Leistner, O.A. & Morris, J.W. (1976) Southern African place names. <em>Annals of the Cape Provincial Museums </em>12: 1–565.</p>
<p>Manning, J.C. & Goldblatt, P. (Eds.) (2012) Plants of the Greater Cape Floristic Region 1: The Core Cape flora. <em>Strelitzia 29</em>. South African National Biodiversity Institute, Pretoria, pp. 853.</p>
<p>Röschenbleck, J., Albers, F., Müller, K., Weinl, S. & Kudla, J. (2014) Phylogenetics, character evolution and a subgeneric revision of the genus <em>Pelargonium</em> (Geraniaceae). <em>Phytotaxa</em> 159 (2): 31–76. https://doi.org/10.11646/phytotaxa.159.2.1</p>
<p>Snijman, D.A. (Ed.) (2013) Plants of the Greater Cape Floristic Region 2: The Extra Cape flora. <em>Strelitzia 30</em>. South African National Biodiversity Institute, Pretoria, pp. 543.</p>
<p>Steudel, E.T. (1841) <em>Nomenklator botanicus, seu, Synonymia plantarum universalis, part 2</em>. J.G. Cottae, Stuttgart, Tübingen, 810 pp. https://doi.org/10.5962/bhl.title.655</p>
<p>Thiers, B. (2021) 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 11 November 2021)</p>
<p>Turczaninow, N. (1858) Animadversiones in secundam partem herbaria Turczaninowiani, nunc universitatis Caesareae Charkowiensis. <em>Bulletin de la Société Impériale des Maturalistes de Moscou</em> 31: 379–476. [https://www.biodiversitylibrary.org/item/151363#page/395/mode/1up]</p>
<p>Van der Walt, J.J.A. (1977) <em>Pelargoniums of southern Africa</em>. Purnell, Cape Town, 51 pp.</p>
<p>Van der Walt, J.J.A. & Vorster, P.J. (1981) <em>Pelargoniums of southern Africa, Vol. 2</em>. Juta, Johannesburg, Cape Town, 149 pp.</p>