Abstract
Recently the genus Phyllogeiton was reinstated to accommodate the two currently recognized species of Berchemia, namely P. discolor and P. zeyheri, which are confined to Africa and Madagascar. In the present contribution a new species, Phyllogeiton trachybasis, is described, illustrated, mapped, and compared with the other members of the genus, especially with P. discolor with which it has hitherto been confused. An identification key and illustrations are provided for the three species of Phyllogeiton. The new species has a restricted range and is presently only known for certain from the KwaZulu-Natal part of the Maputaland Centre of Endemism in South Africa. Known trees of P. trachybasis are mostly old and there are no signs of recruitment in nature. Outside conservation areas, the bark of P. trachybasis is heavily utilised for biocultural purposes, most probably a main reason for the apparent demise of the species. A preliminary conservation assessment suggests that P. trachybasis should be classified as Endangered.
References
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De Winter, B., De Winter, M. & Killick, D.J.B. (1966) Sixty-six Transvaal trees. Botanical Research Institute, Pretoria, 175 pp.
Drummond, R.B. (1966) Rhamnaceae. In: Exell, A.W., Fernandes, A. & Wild, H. (Eds.) Flora zambesiaca 2(2). Flora Zambesiaca Managing Committee, London, pp. 419–439.
Du Randt, F. (2018) The sand forest of Maputaland. South African National Biodiversity Institute, Pretoria, 416 pp.
Dyer, S., James, B. & James, D. (2016) Guide to the properties and uses of southern African wood. Briza Publications, Pretoria, 336 pp.
Dyer, S.T. (1988) Wood fluorescence of indigenous South African trees. IAWA Bulletin n.s. 9: 75–87.
Edwards, D. & Leistner, O.A. (1971) A degree reference system for citing biological records in southern Africa. Mitteilungen der Botanischen Staatssammlung München 10: 501–509. https://biostor.org/reference/185348
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Groenewald, Y. (2010) Ndumo reserve hit by invasion, crime. Mail and Guardian. Available from: https://mg.co.za/article/2010-10-15-ndumo-reserve-hit-by-invasion-crime/ (accessed 23 August 2021)
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Hemsley, W.B. (1868) Order XLII. Rhamneae. In: Oliver, D. (Ed.) Flora of tropical Africa 1. L. Reeve & Co., London, pp. 377–385. https://doi.org/10.5962/bhl.title.42
Herzog, T. (1903) Anatomisch-systematische Untersuchung des Blattes der Rhamneen aus den Triben: Ventilagineen, Zizypheen und Rhamneen. Beihefte zum Botanischen Centralblatt 15: 95–207.
Hill, J. (1768) Hortus kewensis. Baldwin & Ridley, London, pp. 458 + Index.
Huang, X., Deng, T., Chen, S., Landis, J.B., Lin, N., Yang, Y., Hu, G., Zhou, Z., Wang, Y., Wang, H., Tojibaev, K.S. & Sun, H. (2021) Western Tethys origin, tropical Asia and tropical America disjunction in Berchemia and reinstatement of Phyllogeiton (Rhamneae, Rhamnaceae). Taxon 70: 515–525. https://doi.org/10.1002/tax.12498
Hutchings, A., Scott, A.H., Lewis, G. & Cunningham, A.B. (1996) Zulu medicinal plants an inventory. University of Natal Press, Pietermaritzburg in association with University of Zululand, KwaDlangeswa and National Botanical Institute, Claremont, 450 pp.
IUCN (2012) IUCN Red List categories and criteria, version 3.1. IUCN Species Survival Commission, Gland, Switzerland and Cambridge, UK, iv + 32 pp. Available from: https://portals.iucn.org/library/node/10315 (accessed 23 August 2021)
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Johnston, M.C. (1972) Flora of tropical East Africa. Rhamnaceae. Crown Agents for Overseas Governments and Administration, London, 40 pp.
Klotzsch, F. (1862) Frangulaceae Endlicher. In: Peters, W.C.H. (Ed.) Naturwissenschaftliche Reise nach Mossambique (Botanik) 1. Georg Reimer, Berlin, pp. 108–112. https://doi.org/10.5962/bhl.title.52323
Koch, K. (1869) Dendrologie: Bäume, Sträucher und Halbsträucher, welche in Mittel- und Nord-Europa im Freien kultivirt warden, vol. 1. F. Enke, Erlangen, 735 pp. https://doi.org/10.5962/bhl.title.20459
Lindley, J. (1844) Ansellia africana. Edwards’s Botanical Register 30: sub t. 12. [https://www.biodiversitylibrary.org/item/9067#page/48/mode/1up]
Loffler, L. & Loffler, P. (2005) Swaziland tree atlas—including shrubs and climbers, 2nd ed. South African Botanical Diversity Network Report No. 35, SABONET, Pretoria, 196 pp.
Lusepani, N.E. (1999) Reproductive biology and utilisation of Berchemia discolor (Klotzsch) Hemsley (Rhamnaceae). Unpublished MSc thesis, University of Stellenbosch, Stellenbosch, 109 pp.
Mabberley, D. (2017) Mabberley’s plant-book, 4th ed. Cambridge University Press, Cambridge, 1102 pp. https://doi.org/10.1017/9781316335581
Medan, D. & Schirarend, C. (2004) Rhamnaceae. In: Kubitzki, K. (Ed.) The families and genera of vascular plants. VI Dicotyledons: Celastrales, Oxalidales, Rosales, Cornales, Ericales. Springer, Heidelberg, pp. 320–338. https://doi.org/10.1007/978-3-662-07257-8
Moll, E.J. (1981) Trees of Natal. Eco-lab Trust Fund, University of Cape Town, Rondebosch, 570 pp.
Mucina, L. & Rutherford, M.C. (Eds.) (2006) The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria, 807 pp.
Nesom, G.L. (2016) Berchemia Necker ex de Candolle. In: Flora of North America Editorial Committee (Org.) Flora of North America North of Mexico 12. Oxford University Press, New York and Oxford, 59 pp. Available from: http://beta.floranorthamerica.org/Berchemia (accessed 12 June 2021)
Palmer, E.M. (1961) Trees of South Africa. Balkema, Cape Town, 352 pp.
Phillips, E.P. (1951) The genera of South African flowering plants, 2nd ed. Department of Agriculture, Union of South Africa, Pretoria, 923 pp.
Pooley, E. [E.S.] (1993) The complete field guide to trees of Natal, Zululand & Transkei. Natal Flora Publications Trust, Durban, 512 pp.
Pooley, E.S. (1978) A checklist of the plants of Ndumu Game Reserve, north-eastern Zululand. Journal of South African Botany 44: 1–54. [https://archive.org/details/journalofsouthaf44unse/page/n11/mode/2up]
Pooley, E.S. (1980) Some notes on the utilization of natural resources by the tribal people of Maputaland. In: Bruton, M.N. & Cooper, K.H. (Eds.) Studies on the ecology of Maputaland. Rhodes University, Grahamstown and the Natal Branch of the Wildlife Society of Southern Africa, Durban, pp. 467–479.
POWO (2019) Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Available from: http://www.plantsoftheworldonline.org/ (accessed 21 June 2021)
Richardson, J.A., Fay, M.F., Cronk, Q.C.B., Bowman, D. & Chase, M.W. (2000) A phylogenetic analysis of Rhamnaceae using rbcL and trnL-F plastid DNA sequences. American Journal of Botany 87: 1309–1324. https://doi.org/10.2307/2656724
SANBI (2006–2018) National vegetation map project (VEGMAP), ver. 2018. Available from: http://bgis.sanbi.org/Projects/Detail/186 (accessed 9 October 2019)
Schatz, G.E. (2001) Generic tree flora of Madagascar. Royal Botanic Gardens, Kew & Missouri Botanical Garden, St. Louis, 477 pp.
Schmid, R. (1982) Descriptors used to indicate abundance and frequency in ecology and systematics. Taxon 31: 81–94. https://doi.org/10.2307/1220593
Schmidt, E. (2018) Rhamnaceae. In: Burrows, J.E., Burrows, S.M., Lötter, M.C. & Schmidt, E. (Eds.) Trees and shrubs Mozambique. Publishing Print Matters, Noordhoek, Cape Town, pp. 544–552.
Smith, C.A. (1966) Common names of South African plants. Botanical Research Institute, Pretoria, 642 pp.
Sonder, W. (1860) Order XLV. Rhamneae, R. Br. In: Harvey, W.H. & Sonder, O.W. (Eds.) Flora Capensis; being a systematic description of the plants of the Cape Colony, Caffraria & Port Natal 1. Hodges, Smith & Co. Dublin; I.C. Jutta, Cape Town, pp. 475–502. https://doi.org/10.5962/bhl.title.821
Steenkamp, Y., Van Wyk, B. [A.E.], Victor, J., Hoare, D., Smith, G., Dold, T. & Cowling, R. (2004) Maputaland-Pondoland-Albany. In: Mittermeier, R.A., Robles Gil, P., Hoffmann, M., Pilgrim, J., Brooks, T., Goettsch Mittermeier, C., Lamoreux, J. & da Fonseca, G.A.B. (Eds.) Hotspots revisited: Earth’s biologically richest and most threatened terrestrial ecoregions. Cemex & Conservation International, Washington, pp. 219–228.
Suessenguth, K. (1953) Über einige Rhamnales. Mitteilungen der Botanischen Staatssammlung München 6: 181–184.
Temminck, C.J. (1824) Calao trompette Buceros bucinator. In: Nouveau recueil de planches colorieìes d’oiseaux: pour servir de suite et de compleìment aux planches enlumineìes de Buffon, eìdition in-folio et in-4? de l’Imprimerie royale, 1770 (1838), vol. 2, livr. 48, pl. 284. Chez Legras Imbert et Comp, Strasbourgh, p. 99. https://doi.org/10.5962/bhl.title.51468
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