Dr Cornelia Klak

Principal Scientific Officer 
Phone: 021 650 3724 
Room No.: 4.22.2 (HW Pearson Building) 
External page





Research interests

Molecular systematics of succulent plants, with main focus on Aizoaceae, origin and diversification of Aizoaceae, taxonomy of Aizoaceae.

Publications since 2000:

Klak, C. 2000. Taxonomic studies in the Aizoaceae from South Africa: three new species and some new combinations. Bothalia 30: 35-42.

Klak, C., T. Hedderson & H. P. Linder. 2003. A molecular systematic study of the Lampranthus Group (Aizoaceae) based on the chloroplast trnL-trnF and nuclear ITS and 5S NTS sequence data. Systematic Botany 28(1): 70-85.

Klak, C. 2003. New combinations, a new genus and five new species in the Aizoaceae. Bradleya 21: 107-120.

Klak, C., A. Khunou, G. Reeves & T. Hedderson. 2003. A phylogenetic hypothesis for the Aizoaceae (Caryophyllales) based on four plastid DNA regions. American Journal of Botany 90: 1433-1445.

Klak, C., G. Reeves & T. Hedderson. 2004. Unmatched tempo of evolution in Southern African semi-desert ice plants. Nature 427: 63-65.

Bruyns, P.V. & C. Klak. 2004. A phylogenetic hypothesis for and revision of the Madagascan endemic Stapelianthus (Apocynaceae – Asclepiadoideae – Ceropegieae) based on molecular and morphological characters. Annals Missouri Botanical Garden 91: 410-437.

Klak, C. 2005. Ruschiella, a new genus of Aizoaceae and new combinations in Phiambolia and Phyllobolus. Bradleya 23: 97-104.

Bruyns, P.V. & C. Klak. 2006. A systematic study of the old world genus Fockea (Apocynaceae-Asclepiadoideae). Annals Missouri Botanical Garden 93 (4): 535-564.

Klak, C., T. Nowell & T. Hedderson. 2006. Phylogeny and revision of Brownanthus and its close allies Aspazoma and Dactylopsis (Aizoaceae) based on morphology and four DNA regions. Kew Bulletin 61: 353-400.

Klak, C., P.V. Bruyns & T. A. J. Hedderson. 2007. A phylogeny and new classification for Mesembryanthemoideae (Aizoaceae). Taxon 56 (3): 737-756.

Klak, C. 2008. Eight new species of Aizoaceae from the Cedarberg and Namaqualand, South Africa. Bradleya 26: 19-32.

Illing, N., C. Klak, C. Johnson, D. Brito, N. Negrao, F. Baine, V. van Kets, K. Rye Ramchurn, C. Seoighe & L. Roden. 2009: Duplication of the Asymmetric Leaves1/Rough Sheath 2/Phantastica (ARP) gene precedes the explosive radiation of the Ruschioideae. Genes, Evolution and Development 219: 331-338.

Bruyns, P.V. & C. Klak. 2009. The rediscovery and systematic position of Schizostephanus gossweileri and its phylogenetic position. South African Journal of Botany 75(3): 532-536.

Klak, C. 2010. Three new species and two new combinations in the Aizoaceae from the Western and Northern Cape of South Africa. South African Journal of Botany 76: 299-307.

Klak, C. 2010. Phylogeny and diversification of Aizoaceae: progress and prospects. Schumannia 6, Biodiversity & Ecology 3: 87-107.

Klak, C. 2011. New combinations in Antimima and Octopoma (Ruschioideae–Aizoaceae). Bothalia 41(2): 292-294.

Bruyns, P.V., C. Klak & P. Hanáček. 2011. Age and diversity in Old World succulent species of Euphorbia (Euphorbiaceae). Taxon 60 (6): 1717-1733.

Klak, C. & P. V. Bruyns. 2012. Phylogeny of the Dorotheantheae (Aizoaceae), a tribe of succulent annuals. Taxon 61(2): 293-307.

Klak, C. 2012. Two new species of Cleretum  (Ruschioideae-Dorotheantheae, Aizoaceae) from the Northern Cape, South Africa. Haseltonia 18: 29-35.

Klak, C., Bruyns, P. V. & P. Hanácek. 2013. A phylogenetic hypothesis for the recently diversified Ruschieae (Aizoaceae) in southern Africa. Molecular Phylogenetics and Evolution 69: 1005-1020.

Klak, C. & P. V. Bruyns. 2013. A new infrageneric classification for Mesembryanthemum L. (Aizoaceae: Mesembryanthemoideae). Bothalia 43(2): 197-206.

Ripley, B. S., Abraham, T., Klak, C. & Cramer, M.D. 2013. How succulent leaves of Aizoaceae avoid mesophyll conductance limitations of photosynthesis and survive drought. Journal of Experimental Botany, doi:10.1093/jxb/ert314

Bruyns, P. V., C. Klak & P. Hanácek. 2014. Evolution of the stapeliads (Apocynaceae-Asclepiadoideae) – repeated major radiation across Africa in an Old World group. Molecular Phylogenetics and Evolution 77: 251-263.

Klak, C., P. Hanácek & P.V. Bruyns. 2014. Phylogeny and taxonomy for Mesembryanthemum subg. Volkeranthus (Aizoaceae-Mesembryanthemoideae). South African Journal of Botany 95: 112-122.

Melo-de-Pinna, G.F., A.S. Ogura, E.C.P. Arruda & C. Klak. 2014. Repeated evolution of endoscopic peripheral vascular bundles in succulent leaves of Aizoaceae (Caryophyllales). Taxon 63(5): 1037-1052.

Bruyns, P.V., M. Oliveira-Neto, G. F. Melo-de-Pinna2 & C. Klak. 2014. Phylogenetic relationships in the Didiereaceae with special reference to subfamily Portulacarioideae. Taxon 63(5): 1053-1064.

Klak, C., N.A. Helme & P.V. Bruyns. 2015. Cheiridopsis alba-oculata (Aizoaceae: Ruschioideae, Ruschieae), a new quartz-endemic from southern Namaqualand, South Africa. South African Journal of Botany 96: 1-5.

Klak, C., P. Hanáček & P.V. Bruyns. 2015. A phylogeny and revised classification for the Apatesieae (Aizoaceae: Ruschioideae) with a comparison of centres of diversity. Taxon 64 (3): 507–522. DOI

Bruyns, P. V., C. Klak & P. Hanáček. 2015. Recent radiation of Brachystelma and Ceropegia (Apocynaceae) across the Old World against a background of climatic change. Molecular Phylogenetics and Evolution 90: 49-66.

Hernández-Ledesma, P., W.G. Berendsohn, T. Borsch, S. Von Mering, H. Akhani, S. Arias, I. Castañeda-Noa, U. Eggli, R. Eriksson, H. Flores-Olvera, S. Fuentes-Bazán, G. Kadereit, C. Klak, N. Korotkova, R. Nyffeler, G. Ocampo, H. Ochoterena, B. Oxelman, R.K. Rabeler, A. Sanchez, B.O. Schlumpberger & P. Uotila. 2015. A taxonomic backbone for the global synthesis of species diversity in the angiosperm order Caryophyllales. Willdenowia 45 (3): 281-383. DOI:

Klak, C., Bruyns, P.V. 2015. Notes on Ruschia dichroa (Aizoaceae): An endemic to the arid mountain fynbos of the Western Cape, South Africa. Haseltonia 21: 60-67.

Klak, C., Bruyns, P.V. 2016. Expansion of Schlechteranthus (Ruschioideae, Aizoaceae) to include Polymita, with a new species from Namaqualand, South Africa. South African Journal of Botany 103: 70-77.

Powell, R.F., J.S. Boatwright, C. Klak, A.R. Magee. 2016. Phylogenetic placement and generic re-circumscriptions of the multilocular genera Arenifera, Octopoma and Schlechteranthus (Ruschieae; Aizoaceae): evidence from anatomical, morphological and plastid DNA data. Taxon 65 (2): 249–261. DOI

Joubert, L., C. Klak, A.M. Venter, H.J.T. Venter & P.V. Bruyns. 2016. A very widespread tropical radiation in the Apocynaceae (Periplocoideae): The case of Cryptolepis. Taxon 65 (3): 487–501. DOI

Klak, C., P. Hanáček & P.V. Bruyns. 2017. Out of southern Africa: Origin, biogeography and age of the Aizooideae (Aizoaceae). Molecular Phylogenetics and Evolution 109: 203-216.



Klak, C. 2000: Aizoaceae. In P. Goldblatt & J. Manning (eds.), Cape Plants. A conspectus of the Cape Flora of South Africa. Pp. 222-268. Strelitzia 9. NBI, Missouri Botanical Garden.

Chesselet, P., G. F. Smith, P. M. Burgoyne, C. Klak, S. A. Hammer, H. E. K. Hartmann, H. Kurzweil, E. J. van Jaarsveld, B.-E. van Wyk & O. A. Leistner. 2000. Mesembryanthemaceae. Strelitzia 10: 360-410.

Klak, C. & M. Gerbaulet. 2001. Caulipsolon. In H. E. K. Hartmann (ed.) 2001.  Illustrated Handbook of Succulent Plants. Aizoaceae A-E, p. 103. Springer.

Klak, C. & M. Gerbaulet. 2001.  Psilocaulon. In H. E. K. Hartmann (ed.) 2001.  Illustrated Handbook of Succulent Plants. Aizoaceae F-Z, pp. 230-236. Springer.

Klak, C. 2003. Aizoaceae. In: T. Trinder-Smith (ed.), Levyn’s Flora. Contributions from the Bolus Herbarium: 21.

Midgley, G. F., G. Reeves & C. Klak 2005. Late Tertiary and Quaternary climate change and centres of endemism in the southern African flora. In: A. Purvis, J.L. Gittleman & T. Brooks (eds.), Phylogeny and Conservation, pp. 230-242. Cambridge University Press.

Abbott, A.T.D. et al. 2009. In : D. Raimondo, L. von Staden, W. Foden, J.E.Victor, N.A.Helme, R.C. Turner, D.A. Kamundi & P.A. Manyama (eds.), Red List of South African plants 2009. Strelitzia 25. South African Biodiversity Institute, Pretoria.

Klak, C. Aizoaceae. 2012. In Manning, J.C. & Goldblatt, P. (eds.), Plants of the Greater Cape Floristic Region 1: The Core Cape Flora. Pp 165-231. Strelitzia 29.South African Biodiversity Institute, Cape Town. ISBN 978-1-919976-74-7

Klak, C. Aizoaceae. 2013. In: Snijman, D. A. (ed.), Plants of the Greater Cape Floristic Region 2: The Extra Cape Flora. Pp. 260-309. Strelitzia 30. South African Biodiversity Institute, Cape Town. ISBN 978-1-919976-77-8


Popular articles:

Klak, C. 2001. Die Gattung Lampranthus (Ruschioideae, Aizoaceae) in Südafrika. Kakteen und andere Sukkulenten 52: 29-36.

Klak, C. 2002. Recent studies in Lampranthus N.E.Br. Mesemb Study Group Bulletin 17: 70-75.

Klak, C. 2003. An introduction to Brownanthus N.E.Br. Mesemb Study Group Bulletin 18: 24-29.

Klak, C. 2004. Aizoaceae or Mesembryanthemaceae ?: New evidence from DNA. Mesemb Study Group Bulletin 19: 29-36.

Klak, C. 2007. Lost and found again: Circandra serrata. Mesemb Study Group Bulletin 22 (2): 27.

Klak, C. & Low, B. 2007. The re-discovery of a long lost vygie, Circandra serrata. Veld & Flora 93 (2): 73.

Klak, C. 2008. A new classification for the Mesembryanthemoideae (Aizoaceae). Cactus World 26: 71-80.

Klak, C. 2013. In search of succulents in Botswana. Mesemb Study Group Bulletin 28: 37-40.

Klak, C. 2013. Bokbaai vygies reclassified. Aloe 50(3): 92-97.

Klak, C. 2015. Apatesieae: distribution, new generic relationships and a novel subspecies in Hymenogyne. Mesemb Study Group Bulletin 30(4): 91-96.