Abstract
A novel species of Ceropegia sect. Bowkerianae (Apocynaceae: Asclepiadoideae-Ceropegieae-Stapeliinae), C. stylesii, is described from Ngome in northern KwaZulu-Natal, South Africa. This new species is vegetatively similar to C. gerrardii. The rotate non-trapping flowers of C. stylesii superficially appear to be miniature versions of a dark-flowered form of C. gerrardii, with which it is sympatric. Ceropegia stylesii is exceptionally rare with fewer than 10 individuals observed at two localities; its habitat is under anthropogenic threat. Ceropegia stylesii is considered as Critically Endangered (CR) according to IUCN criteria.
References
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<p>Bruyns, P., Klak, C. & Hanáček, P. (2017) A revised, phylogenetically-based concept of <em>Ceropegia </em>(Apocynaceae). <em>South African Journal of Botany</em> 112: 399–436. https://doi.org/10.1016/j.sajb.2017.06.021</p>
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<p>Dyer, R. (1977) Asclepiadaceae. <em>Bothalia </em>12 (2): 255–256.</p>
<p>Dyer, R.A. (1983) <em>Ceropegia, Brachystelma and Riocreuxia in Southern Africa</em>. Balkema, Rotterdam, 242 pp.</p>
<p>Endress, M.E., Meve, U., Middleton, D.J. & Liede-Schumann, S. (2019 [‘2018’]) Apocynaceae. <em>In</em>: Kadereit, J.W. & Bittrich, V. (Eds.) <em>Flowering Plants. The Families and Genera of Vascular Plants, Vol. 15, Eudicots, Apiales, Gentianales (excl. Rubiaceae).</em> Heidelberg, New York: Springer, pp. 207–411. https://doi.org/10.1007/978-3-319-93605-5_3</p>
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<p>Hilliard, O.M. (1982) <em>Helichrysum ingomense</em> Hilliard. <em>Notes of the Royal Botanic Garden Edinburgh</em> 40 (2): 255. https://doi.org/10.4102/abc.v12i2.1409</p>
<p>Hilliard, O.M. (1988) <em>Dierama erectum </em>Hilliard. <em>Notes of the Royal Botanic Garden Edinburgh </em>45 (1): 80.</p>
<p>Hilliard, O.M. & Burt, B.L. (1986) <em>Dracosciadium italae </em>Hilliard & B.L.Burtt. <em>Notes from the Royal Botanic Garden, Edinburgh </em>43 (2): 223.</p>
<p>Hooker, W.J. & Arnott, G.A.W. (1838) <em>Andropogon caesius</em> Nees ex Hook. & Arn. <em>Botany of Captain Beechey‘s Voyage: </em>244.</p>
<p>Huber, H. (1957) Revision der Gattung <em>Ceropegia</em>. <em>Memórias da Sociedade Broteriana</em> 12: 1–203.</p>
<p>Hyde, M.A., Wursten, B., Ballings, P., Dondeyne, S. & Coates Palgrave, M. (2022) Genus page: <em>Ceropegia</em>. <em>Flora of Mozambique</em>. [https://www.mozambiqueflora.com/speciesdata/genus.php?genus_id=1153]</p>
<p>IUCN Standards and Petitions Committee (2022) <em>Guidelines for Using the IUCN Red List Categories and Criteria</em>. Version 15.1. Prepared by the Standards and Petitions Committee, 114 pp. Available from: https://www.iucnredlist.org/resources/redlistguidelines (accessed 20 December 2022)</p>
<p>Linnaeus, C. von (1753) <em>Species Plantarum</em>, vol. 1. et vol. 2. Imprensis Laurentii Salvii, Holmiae, pp. 1–560. (Vol.1), pp. 561–1200 (Vol. 2).</p>
<p>Masinde, P.S. (2007) A revision of <em>Brachystelma </em>Sims (Apocynaceae: Asclepiadoideae-Ceropegieae) in East Africa. <em>Kew Bulletin</em> 62: 37–84.</p>
<p>Masinde, P.S (2012) <em>Ceropegia</em>. <em>In</em>: Beentje, H. (Ed.) <em>Flora of Tropical East Africa. Apocynaceae (Part 2)</em>. Kew: Royal Botanic Gardens, pp. 220–291.</p>
<p>Meve, U. & Liede, S. (2004) Subtribal Division of Ceropegieae (Apocynaceae-Asclepiadoideae). <em>Taxon</em> 53 (1): 61–72. https://doi.org/10.2307/4135489</p>
<p>Meve, U. & Liede-Schumann, S. (2007) <em>Ceropegia</em> (Apocynaceae, Ceropegieae, Stapeliinae): paraphyletic but still taxonomically sound. <em>Annals of the Missouri Botanical Garden</em> 94 (2): 392–406. https://doi.org/10.3417/0026-6493(2007)94[392:CACSPB]2.0.CO;2</p>
<p>Mucina, L., Hoare, D.B., Lötter, M.C., Du Preez, J., Rutherford, M.C., Scott-Shaw, C.R., Bredenkamp, G.J., Powrie, L.W., Scott, L., Camp, K.G.T., Cilliers, S.S., Bezuidenhout, H., Mostert, T.H., Siebert, S.J., Winter, P.J.D., Burrows, J.E., Dobson, L., Ward, R.A., Stalmans, M., Oliver, E.G.H., Siebert, F., Schmidt, E., Kobisi, K. & Kose, L. (2006) Grassland Biome. <em>In</em>: Mucina, L. & Rutherford, M.C. (Eds.) <em>The vegetation of South Africa, Lesotho and Swaziland</em>. Pretoria. Strelitzia, South Africa, pp. 349–436.</p>
<p>Oliver, D. (1883) <em>Lasiostelma sandersonii</em> Oliv. <em>Hooker‘s Icones Plantarum</em> 15: t. 1449.</p>
<p>Ollerton, J., Dötterl, S., Ghorpadé, K., Heiduk, A., Liede-Schumann, S., Masinde, S., Meve, U., Craig, P.I., Prieto-Benítez, S., Punekar, S., Thulin, M. & Whittington, A. (2017) Diversity of Diptera families that pollinate <em>Ceropegia </em>(Apocynaceae) trap flowers: an update in light of new data and phylogenetic analyses. <em>Flora</em> 234: 233–244. https://doi.org/10.1016/j.flora.2017.07.013</p>
<p>Ollerton, J., Liede-Schumann, S., Endress, M.E., Meve, U., Rech, A.R., Shuttleworth, A., Keller, H.A., Fishbein, M., Alvarado-Cárdenas, L.O., Amorim, F.W., Bernhardt, P., Celep, F., Chirango, Y., Chiriboga-Arroyo, F., Civeyrel, L., Cocucci, A., Cranmer, L., da Silva-Batista, I.C., de Jager, L., Scaramussa Deprá, M., Domingos-Melo, A., Dvorsky, C., Agostini, K., Freitas, L., Gaglianone, M.C., Galetto, L., Gilbert, M., González-Ramírez, I., Gorostiague, P., Goyder, D., Hachuy-Filho, L., Heiduk, A., Howard, A., Ionta, G., Islas-Hernández, S.C., Johnson, S.D., Joubert, L., Kaiser-Bunbury, C.N., Kephart, S., Kidyoo, A., Koptur, S., Koschnitzke, C., Lamborn, E., Livshultz, T., Machado, I.C., Marino, S., Mema, L., Mochizuki, K., Cerdeira Morellato, L.P., Mrisha, C.K., Muiruri, E.W., Nakahama, N., Teixeira Nascimento, V., Nuttman, C., Oliveira, P.E., Peter, C.I., Punekar, S., Rafferty, N., Rapini, A., Ren, Z.-X., Rodríguez-Flores, C.I., Rosero, L., Sakai, S., Sazima, M., Steenhuisen, S.-L., Tan, C.-W., Torres, C., Trøjelsgaard, K., Ushimaru, A., Vieira, M.F., Wiemer, A.P., Yamashiro, T., Nadia, T., Queiroz, J. & Quirino, Z. (2019) The diversity and evolution of pollination systems in large plant clades: Apocynaceae as a case study. <em>Annals of Botany </em>123: 311–325. https://doi.org/10.1093/aob/mcy127</p>
<p>Raimondo, D., von Staden, L., Foden, W., Victor, J.E., Helme, N.A., Turner, R.C., Kamundi, D.A. & Manyama, P.A. (2009) Red List of South African Plants. <em>Strelitzia</em> 25: 1–668.</p>
<p>Reichenbach, H.G. (1867) <em>Brachycorythis gerrardii </em>Rchb.f. <em>Flora </em>50: 116.</p>
<p>Schlechter, R. (1894a) <em>Sisyranthus schizoglossoides</em> Schlechter. <em>Journal of Botany</em> <em>British and Foreign</em> 32: 357.</p>
<p>Schlechter, R. (1894b) Beiträge zur Kenntnis südafrikanischer Asclepiadaceen. <em>Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie</em> 18, Beibl. 45: 1–37.</p>
<p>Schlechter, R. (1895) Beitrage zur Kenntnis südafrikanischer Asclepiadaceen. <em>Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie</em> 20, Beibl. 51: 1–56.</p>
<p>Schlechter, R. (1907) Beiträge zur Kenntnis der Flora von Natal. <em>Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie </em>40: 8–96.</p>
<p>Schultz, C.H. Bipontinus (1844) <em>Gerbera aurantiaca </em>Sch.Bip. <em>Flora oder allgemeine botanische Zeitung </em>27 (2): 781.</p>
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