Skip to main content Skip to main navigation menu Skip to site footer
Responsive image
Issue: Vol. 628 No. 1: 29 Nov. 2023
Type: Monograph
Published: 2023-11-29
DOI: 10.11646/phytotaxa.628.1.1
Page range: 1-64
Abstract views: 275
PDF downloaded: 30

A taxonomic revision of Aloe sect. Purpurascentes (Asphodelaceae subfam. Alooideae)

Foundational Biodiversity Sciences Division; South African National Biodiversity Institute; Private Bag X101; Pretoria; 0001; South Africa. H.G.W.J. Schweickerdt Herbarium; Department of Plant and Soil Sciences; University of Pretoria; Pretoria; 0002; South Africa.
Royal Botanic Gardens; Kew; Surrey TW9 3AE; United Kingdom. Royal Botanic Garden Edinburgh; 20A Inverleith Row; Edinburgh EH3 5LR; United Kingdom
Molecular Ecology and Evolution Programme; Department of Biochemistry; Genetics and Microbiology; University of Pretoria; Pretoria; 0002; South Africa
Ria Olivier Herbarium; Department of Botany; P.O. Box 77000; Nelson Mandela University; Gqebergha; 6031; South Africa
Foundational Biodiversity Sciences Division; South African National Biodiversity Institute; Private Bag X101; Pretoria; 0001; South Africa. H.G.W.J. Schweickerdt Herbarium; Department of Plant and Soil Sciences; University of Pretoria; Pretoria; 0002; South Africa.
Monocots ITS matK morphological characters Namibia South Africa speckled aloes taxonomy typification

Abstract

Aloe sect. Purpurascentes, or the speckled aloes (not to be confused with the maculate aloes, which are members of A. sect. Pictae), occurs in southern and western South Africa and southern Namibia. This section is here revised using macro-morphology, seed morphology, palynology, chemistry, and molecular evidence. Seed morphology, palynology, chemistry, and to a greater extent molecular markers, are shown to be inconclusive for demarcation at species level in A. sect. Purpurascentes. Nonetheless, evidence from these sources does provide support for the general coherence of the group. Although some species can be clearly differentiated from most other members of A. sect. Purpurascentes, the results are not consistent among the different character sets investigated. No changes are thus proposed here in terms of the placement of taxa within the section. Two species suspected to be members of the section under study (A. pictifolia and A. chlorantha), although being chemically related, do not cluster with the rest of the members of A. sect. Purpurascentes in the morphological analysis, and evidence on the sectional placement of these taxa from molecular analyses is inconclusive. Hence, these two aloes are here excluded from A. sect. Purpurascentes. The most useful evidence to distinguish among taxa in A. sect. Purpurascentes were those from comparative morphology. In this revision five species are retained: A. framesii, A. gariepensis, A. khamiesensis, A. microstigma, and A. succotrina. The following taxonomic changes are proposed: A. knersvlakensis becomes a subspecies of A. khamiesensis; aberrant populations of the latter species from the Hantam region are described as A. khamiesensis subsp. hantamensis; A. juttae is reinstated at subspecific level under A. microstigma; A. amoena is reinstated at subspecific level under A. framesii, and a third subspecies, A. framesii subsp. maraisii, is described for the southern populations of this aloe. Lectotypes are designated for five names and epitypes for three names. The notion that DNA barcodes should not be seen as a replacement technique for comprehensive taxonomic analysis is clearly illustrated in this revision of A. sect. Purpurascentes. Since traditional barcodes are insufficient to distinguish samples at species level, alpha taxonomic techniques are essential to delimit species in this group of aloes, and likely for all other aloes.

 

References

  1. Adams, S.P., Leitch, I.J., Bennett, M.D., Chase, M.W. & Leitch, A.R. (2000) Ribosomal DNA evolution and phylogeny in Aloe (Asphodelaceae). American Journal of Botany 87(11): 1578–1583. https://doi.org/10.2307/2656733
  2. Aiton, W. (1789) Hortus Kewensis 1. George Nicol, London, 496 pp. https://doi.org/10.5962/bhl.title.4504
  3. Allioni, C. (1773) Auctarium ad synopsim methodicam stirpium horti regii taurinensis. Melanges de Philosophie et de Mathematique de la Societé Royale de Turin pour les années 1770–1773, 5: 53–96. [https://www.biodiversitylibrary.org/item/32648#page/73/mode/1up]
  4. Avise, J.C., Ankney, C.D. & Nelson, W.S. (1990) Mitochondrial gene trees and the evolutionary relationships of Mallard and Black ducks. Evolution 44 (4): 1109–1119. https://doi.org/10.2307/2409570
  5. Avise, J.C., Arnold, J., Ball, R.M., Bermingham, E., Lamb, T., Neigel, J.E., Reeb, C.A. & Saunders, N.C. (1987) Intraspecific phylogeography: the bridge between population genetics and systematics. Annual Review of Ecology & Systematics 18: 489–522. https://doi.org/10.1146/annurev.es.18.110187.002421
  6. Beaumont, J., Reynolds, T. & Vaughan, J.G. (1984) Homonataloin in Aloe species. Planta Medica 50 (6): 505–508. https://doi.org./10.1055/s-2007-969784
  7. Berger, A. (1905) Liliaceae–Aloïneae africanae. Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 38: 84–87. [https://www.biodiversitylibrary.org/item/700#page/94/mode/1up]
  8. Berger, A. (1908) Liliaceae-Asphodeloideae-Aloineae. In: Engler, A. & Prantl, K. (Eds.) Das Pflanzenreich IV. 38 (Heft 33). Engelmann, Leipzig, 347 pp. [https://www.biodiversitylibrary.org/item/68230#page/5/mode/1up]
  9. Bester, S.P., Klopper, R.R. & Steyn, H.M. (2012) New plant records for Tankwa Karoo National Park, South Africa. Koedoe 54: Art. #1066, 9 pages. http://doi.org/10.4102/koedoe.v54i1.1066
  10. Bolus, L. (1933) Plants, new or noteworthy. South African Gardening and Country Life 23: 140.
  11. Botes, C., Wragg, P.D. & Johnson, S.D. (2009) New evidence for bee-pollination systems in Aloe (Asphodelaceae: Alooideae), a predominantly bird-pollinated genus. South African Journal of Botany 75 (4): 675–681. https://doi.org/10.1016/j.sajb.2009.07.010
  12. Britton, N.L. & Millspaugh, C.F. (1920) The Bahama flora. Privately published, New York, 695 pp. https://doi.org/10.5962/bhl.title.1494
  13. Burman, N.L. (1768) Flora Indica, Prodromus Florae Capensis. Leiden, Amsterdam, 34 pp. [https://www.biodiversitylibrary.org/item/123275#page/201/mode/1up]
  14. Cammerloher, H. (1933) Aloe brunnthaleri Berger. Kakteenkunde 1933 (7): 131–132.
  15. Carter, S., Lavranos, J.J., Newton, L.E. & Walker, C.C. (2011) Aloes, the definitive guide. Royal Botanic Gardens, Kew, 719 pp.
  16. Castillon, J.-B. (2000) Deux nouvelles espèces d’Aloe (Liliaceae) de Madagascar. Adansonia, ser.3, 22: 135–138. [https://sciencepress.mnhn.fr/fr/periodiques/adansonia/22/1/deux-nouvelles-especes-d-aloe-liliaceae-de-madagascar]
  17. Castillon, J.-B. (2007) Aloe werneri and Aloe ampefyana, two new Aloe (Asphodelaceae) species from Madagascar. Haseltonia 13: 23–28. https://doi.org/10.2985/1070-0048(2007)13[23:AWAAAT]2.0.CO;2
  18. Castillon, J.-B. (2011) Two new Aloe taxa (Asphodelaceae) from the vicinity of the town of Ambatofinandrahana, Madagascar. CactusWorld 29 (1): 51–55. [https://www.jstor.org/stable/42795205]
  19. Castillon, J.-B. & Castillon, J.-P. (2010) Les aloe de Madagascar / The aloe of Madagascar. J.-B. & J.-P. Castillon, Reunion, 399 pp.
  20. CBOL Plant Working Group. (2009) A DNA barcode for land plants. Proceedings of the National Academy of Sciences of the United States of America 106 (31): 12794–12797. https://doi.org/10.1073/pnas.0905845106
  21. Chase, M.W. & Fay, M.F. (2009) Barcoding of plants and fungi. Science 325 (5941: 682–683). https://doi.org/10.1126/science.1176906
  22. Chase, M.W., De Bruijn, A.Y., Cox, A.V., Reeves, G., Rudall, P.J., Johnson, M.A.T. & Eguiarte, L.E. (2000) Phylogenetics of Asphodelaceae (Asparagales): an analysis of plastid rbcL and trnL-F DNA sequences. Annals of Botany 86 (5): 935–951. https://doi.org/10.1006/anbo.2000.1262
  23. Chauser-Volfson, E. & Gutterman, Y. (1996) The barbaloin content and distribution in Aloe arborescens leaves according to the leaf part, age, position and season. Israel Journal of Plant Sciences 44 (4): 289–296. https://doi.org/10.1080/07929978.1996.10676652
  24. China Plant BOL Group. (2011) Comparative analysis of a large dataset indicates that internal transcribed spacer (ITS) should be incorporated into the core barcode for seed plants. Proceedings of the National Academy of Sciences of the United States of America 108 (49): 19641–19646. https://doi.org/10.1073/pnas.1104551108
  25. CITES. (2023) CITES Appendices I, II and III. Available online at http://www.cites.org/eng/app/appendices.php (accessed July 2023)
  26. Compton, J.S. (2004) The rocks & mountains of Cape Town. Double Story, Cape Town, 112 pp.
  27. Commelin, J. (1697) Horti medici Amstelodamensis rariorum tam orientalis quam occidentalis Indiae, aliarumque perergrinarum plantarum magno studio ac labore, sumptibus civitatis Amstelodamensis longa annorum serie collectarum: descriptio et icons ad vivum aeri incisae. Pars prima. Blaeu, Amsterdam, 220 pp. https://doi.org/10.5962/bhl.title.820
  28. Dagne, E., Bisrat, D., Van Wyk, B-E., Viljoen, A., Hellwig, V. & Steglich, W. (1997) Anthrones from Aloe microstigma. Phytochemistry 44 (7): 1271–1274. https://doi.org/10.1016/S0031-9422(96)00710-8
  29. Daru, B.H., Manning, J.C., Boatwright, J.S., Maurin, O., Maclean, N., Schaefer, H., Kuzmina, M. & Van der Bank, M. (2013) Molecular and morphological analysis of subfamily Alooideae (Asphodelaceae) and the inclusion of Chortolirion in Aloe. Taxon 62 (1): 62–76. https://doi.org/10.1002/tax.621006
  30. De Almeida, R.F., Pellegrini, M.O.O., De Morais, I.L., Simão-Bianchini, R., Rattanakrajang, P., Cheek, M. & Simões, A.R.G. (2023) Barking up the wrong tree: the dangers of taxonomic misidentification in molecular phylogenetic studies. Plant Ecology and Evolution 156 (2): 146–159. https://doi.org/10.5091/plecevo.101135
  31. De Candolle, A.P. (1801) Historia plantarum succulentarum. Histoire des plantes grasses 2. A.J. Dugour et Durand, Paris, 51 tab. https://doi.org/10.5962/bhl.title.503
  32. Dillenius, J.J. (1732) Hortus Elthamensis, Vol. 1. Sumptibus Auctris, London, 204 pp., 166 Tab. https://bibdigital.rjb.csic.es/idurl/1/10700
  33. Dinter, M.K. (1923) Beiträge zur Flora von Südwestafrika 1. Feddes Repertorium Specierum Novarum Regni Vegetabilis 19 (8–10): 122–160. https://doi.org/10.1002/fedr.19230190807
  34. Dinter, M.K. (1928) Sukkulentenforschung in Südwestafrika 2. Erlebnisse und Ergebnisse meiner Reise in den Jahren 1923 bis 1925. Repertorium Specierum Novarum Regni Vegetabilis Beihefte 53: 1–145.
  35. Duval, H.A. (1809) Plantae Succulentae in Horto Alenconio. Gabon, Paris, 18 pp.
  36. Edgar, R.C. (2004) MUSCLE: multiple sequence alignment with high accuracy and high throughput. Nucleic Acids Research 32 (5): 1792–1797. https://doi.org/10.1093/nar/gkh340
  37. Ellis, K. (2013) Revision of Aloiampelos Klopper & Gideon F.Sm. (Xanthorrhoeaceae subfam. Asphodeloideae). Unpublished M.Sc. thesis, Nelson Mandela Metropolitan University, Port Elizabeth, 126 pp. https://doi.org/10.13140/2.1.3206.4804
  38. Engler, H.G.A. (1888) Plantae Marlothianae. Ein Beitrag zur Kenntnis der Flora Südafrikas. Botanische Jahrbücher fur Systematik 10: 1–50. [https://www.biodiversitylibrary.org/item/684#page/10/mode/1up]
  39. Excoffier, L., Smouse, P.E. & Quattro, J.M. (1992) Analysis of molecular variance inferred from metric distances among DNA haplotypes: application to human mitochondrial DNA restriction data. Genetics 131 (2): 479–491. https://doi.org/10.1093/genetics/131.2.479
  40. Farr, E.R. & Zijlstra, G. (Eds.) (1996+) Index Nominum Genericorum (Plantarum). Available from: http://botany.si.edu/ing (accessed July 2021).
  41. Fazekas, A.J., Burgess, K.S., Kesanakurti, P.R., Graham, S.W., Newmaster, S.G., Husband, B.C., Percy, D.M., Hajibabaei, M. & Barrett, C.H. (2008) Multiple multilocus DNA barcodes from the plastid genome discriminate plant species equally well. PLoS ONE 3 (7): e2802, 12 pp. https://doi.org/10.1371/journal.pone.0002802
  42. Ford, C.S., Ayres, K.L., Toomey, N., Hai, N., Van Alphen Stahl, J., Kelly, L.J., Wikström, N., Hollingsworth, P., Duff, R.J., Hoot, S.B., Cowan, R.S., Chase, M.W. & Wilkinson, M.L. (2009) Selection of candidate DNA barcoding regions for use on land plants. Botanical Journal of the Linnean Society 159 (1): 1–11. https://doi.org/10.1111/j.1095-8339.2008.00938.x
  43. Forster, P.I. (2003) Aloe bruynsii (Asphodelaceae: Alooideae), a new species from Madagascar. Bradleya 21: 53–56. https://doi.org/10.25223/brad.n21.2003.a11
  44. Garsault, F.A. de (1764) Les figures des plantes et animaux d’usage en medecine, décrits dans la Matiere Medicale de Geoffroy Medecin 1. Desprez, Paris, 118 tab. https://doi.org/10.5962/bhl.title.49481
  45. Glen, H.F. & Hardy, D.S. (2000) Aloaceae (First part): Aloe. In: Germishuizen, G. (Ed.) Flora of Southern Africa 5, Part 1, Fascicle 1. National Botanical Institute, South Africa, 167 pp. [https://www.biodiversitylibrary.org/item/209564#page/3/mode/1up]
  46. Grace, O.M. & Klopper, R.R. (2014) Recommendation to the CITES Plants Committee: name changes affecting Aloe and related genera. 21st meeting of the CITES Plants Committee, PC21 Doc. 20.2. Available online at: http://cites.org/sites/default/files/eng/com/pc/21/E-PC21-20-2.pdf (accessed July 2022).
  47. Grace, O.M. & Rønsted, N. (2013) Unlocking the secrets of DNA in the classification of aloes. Aloe 50: 22–23.
  48. Grace, O.M., Buerki, S., Symonds, M.R.E., Forest, F., Van Wyk, A.E., Smith, G.F., Klopper, R.R., Bjorå, C.S., Neale, S., Sebsebe Demissew, Simmonds, M.S.J. & Rønsted, N. (2015) Evolutionary history and leaf succulence as explanations of medicinal use in aloes and the global popularity of Aloe vera. BMC Evolutionary Biology 15: a29, 12 pp. https://doi.org/10.1186/s12862-015-0291-7
  49. Grace, O.M., Dzajic, A., Jäger, A.K., Nyberg, N.T., Önder, A. & Rønsted, N. (2013b) Monosaccharide analysis of succulent leaf tissue in Aloe. Phytochemistry 93: 79–87. https://doi.org/10.1016/j.phytochem.2013.03.015
  50. Grace, O.M., Klopper, R.R., Figueiredo, E. & Smith, G.F. (2011) The Aloe Names Book. Strelitzia 28. South African National Biodiversity Institute, Pretoria; Royal Botanic Gardens, Kew, 232 pp. [http://hdl.handle.net/20.500.12143/270]
  51. Grace, O.M., Klopper, R.R., Smith, G.F., Crouch, N.R., Figueiredo, E., Rønsted, N. & Van Wyk, A.E. (2013a) A revised generic classification for Aloe (Xanthorrhoeaceaea subfam. Asphodeloideae). Phytotaxa 76 (1): 7–14. https://doi.org/10.11646/phytotaxa.76.1.2
  52. Grace, O.M., Simmonds, M.S.J., Smith, G.F. & Van Wyk, A.E. (2010) Chemosystematic evaluation of Aloe section Pictae (Asphodelaceae). Biochemical Systematics & Ecology 38 (1): 57–62. https://doi.org/10.1016/j.bse.2009.10.009
  53. Guglielmone, L., Gallo, L., Meregalli, M., Smith, G.F. & Figueiredo, E. (2009) Allioni’s Aloe names (Asphodelaceae): nomenclature and typification. Bothalia 39 (2): 177–183. https://doi.org/10.4102/abc.v39i2.243
  54. Guillaumin, A. (1950) Plantes nouvelles, rares ou critiques des serres du Muséum. Bulletin du Muséum National d’Histoire Naturelle sér. 2, 21: 722–724. [https://www.biodiversitylibrary.org/page/54382861#page/754/mode/1up]
  55. Hajibabaei, M., Singer, G.A.C., Hebert, P.D.N. & Hickey, D.A. (2007) DNA barcoding: how it complements taxonomy, molecular phylogenetics and population genetics. Trends in Genetics 23 (4): 167–172. https://doi.org/10.1016/j.tig.2007.02.001
  56. Hanáček, P., Klak, C. & Bruyns, P.V. (2023) A new species of Gonialoe from southern Angola. South African Journal of Botany 159: 653–657. https://doi.org/10.1016/j.sajb.2023.06.040
  57. Hardy, D.S. (1976) A new species of Aloe from the Humansdorp district. Bothalia 12 (1): 62–64. https://doi.org/10.4102/abc.v12i1.1378
  58. Haworth, A.H. (1804) A new arrangement of the genus Aloe. Transactions of the Linnean Society of London 7: 1–28. [https://www.biodiversitylibrary.org/item/13717#page/45/mode/1up]
  59. Haworth, A.H. (1812) Synopsis Plantarum Succulentarum. Taylor, London, 207 pp. https://doi.org/10.5962/bhl.title.9462
  60. Haworth, A.H. (1824) Decas Secunda Novarum Plantarum Novarum Succulentarum. Philosophical Magazine & Journal 64: 298–302. [https://www.biodiversitylibrary.org/item/53102#page/324/mode/1up]
  61. Haworth, A.H. (1825) Decas Quinta Novarum Plantarum Succulentarum. Philosophical Magazine & Journal 66: 279–283.
  62. [https://www.biodiversitylibrary.org/item/53098#page/301/mode/1up]
  63. Herbin, G.A. & Robins, P.A. (1968) Studies on plant cuticular waxes – I. The chemotaxonomy of alkanes and alkenes of the genus Aloe L. (Liliaceae). Phytochemistry 7 (2): 239–255. https://doi.org/10.1016/S0031-9422(00)86322-0
  64. Hillis, D.M. (1987) Molecular versus morphological approaches to systematics. Annual Review of Ecology & Systematics 18: 23–42. https://doi.org/10.1146/annurev.es.18.110187.000323
  65. Hollingsworth, P.M., Graham, S.W. & Little, D.P. (2011) Choosing and using a plant DNA barcode. PLoS ONE 6: e19254, 13 pp. https://doi.org/10.1371/journal.pone.0019254
  66. IPNI. (2023+) The International Plant Names Index. Available from: https://www.ipni.org/ (continuously updated; accessed July 2023).
  67. IUCN Red List of Threatened Species. (2023) Version 2021.3. Available online at www.iucnredlist.org (accessed July 2023).
  68. Kamstra, M.W. (1968) Aloe seeds. Aloe 6: 8–10, 23–27.
  69. Kamstra, M.W. (1971) Aloe seeds. Excelsa 1: 19–26.
  70. Kemble, B. (2011) The speckled aloes. Cactus and Succulent Journal (U.S.) 83: 27–30. https://doi.org/10.2985/0007-9367-83.1.39
  71. Ker Gawler, J.B. (1812) Aloe soccotrina (β) purpurascens. Largest Soccotrine aloe. Curtis’s Botanical Magazine 36: t.1474. [https://www.biodiversitylibrary.org/item/14321#page/159/mode/1up]
  72. Klopper, R.R. (2014) Contributions to the systematic of the genus Aloe L. (Asphodelaceae: Alooideae) in southern Africa. PhD thesis, University of Pretoria, Pretoria.
  73. Klopper, R.R. & Smith, G.F. (2009) Asphodelaceae: Aloe hahnii, a new species in the Section Pictae, in the Soutpansberg Centre of Endemism, Limpopo Province, South Africa. Bothalia 39 (1): 98–100. https://doi.org/10.4102/abc.v39i1.233
  74. Klopper, R.R. & Smith, G.F. (2010) Asphodelaceae: Reinstatement of Aloe spectabilis Reynolds. Bothalia 40 (1): 91–93. https://doi.org/10.4102/abc.v40i1.197
  75. Klopper, R.R., Grace, O.M., Smith, G.F. & Figueiredo, E. (2011) Reinstatement of Aloe graciliflora Groenew. (Asphodelaceae: Alooideae), a maculate aloe from north-east South Africa. Bradleya 29: 125–130. https://doi.org/10.25223/brad.n29.2011.a15
  76. Klopper, R.R., Smith, G.F., Grace, O.M. & Crouch, N.R. (2014) Reinstatement of Aloe barbertoniae (Asphodelaceae: Alooideae) from northeastern South Africa. Bradleya 32: 70–75. https://doi.org/10.25223/brad.n32.2014.a21
  77. Klopper, R.R., Smith, G.F., Figueiredo, E. & Van Wyk, A.E. (2016) (2469–2472) Proposals to reject the names Aloe perfoliata, A. obscura, A. picta, and A. perfoliata var. saponaria (A. saponaria) (Asphodelaceae: Alooideae). Taxon 65 (5): 1173–1175. https://doi.org/10.12705/655.22
  78. Klopper, R.R., Van Wyk, A.E. & Smith, G.F. (2010) Phylogenetic relationships in the family Asphodelaceae (Asparagales). Schumannia 6 / Biodiversity & Ecology 3: 1–36.
  79. Lahaye, R., Van Der Bank, M., Bogarin, D., Warner, J., Pupulin, F., Gigot, G., Maurin, O., Duthoit, S. Barraclough, T.G. & Savolainen, V. (2008) DNA barcoding the floras of biodiversity hotspots. Proceedings of the National Academy of Sciences 105 (8): 2923–2928. https://doi.org/10.1073/pnas.0709936105
  80. Lamarck, J.B.A.P.M. de (1783) Encyclopédie Méthodique, Botanique 1. Panckoucke, Paris, 748 pp. https://doi.org/10.5962/bhl.title.824
  81. Lavranos, J.J. (1973) Aloe chlorantha: a new species from the southwestern Karoo (South Africa). Journal of South African Botany 39 (1): 85–90. [https://archive.org/details/journalofsouthaf39unse/page/84/mode/2up]
  82. Lavranos, J.J. (2004) Aloe striata Haw. and its associates: reflections on consistency in taxonomic treatment. Aloe 42: 50–51.
  83. Linnaeus, C. (1753) Species Plantarum 1. Impensis Laurentii Salvii, Stockholm, 560 pp. https://doi.org/10.5962/bhl.title.37656
  84. Lunau, K. (1995) Innate colour preferences of flowers visitors. Journal of Comparative Physiology A 177: 1–19.
  85. Maddison, W.P. & Maddison, D.R. (2015) Mesquite: a modular system for evolutionary analysis. Version 3.02. Available from: https://mesquiteproject.org (accessed February 2015).
  86. Makino, T.T. & Ohashi, K. (2017) Honest signals to maintain a long-lasting relationship: floral colour change prevents plant-level avoidance by experienced pollinators. Functional Ecology 31: 831–837. https://doi.org/10.1111/1365-2435.12802
  87. Manning, J.C., Boatwright, J.S., Daru, B.H., Maurin, O. & Van der Bank, M. (2014) A molecular phylogeny and genetic classification of Asphodelaceae subfamily Alooideae: A final resolution of the prickly issue of polyphyly in the alooids? Systematic Botany 39 (1): 55–74. https://doi.org/10.1600/036364414X678044
  88. Marais, S.J. (2010) Aloe knersvlakensis, a new aloe from the north-eastern Knersvlakte. Aloe 47: 96–99.
  89. Marloth, H.W.R. (1910) Some new South African succulents. Part II. Transactions of the Royal Society of South Africa 1 (2): 403–409. https://doi.org/10.1080/00359191009520051
  90. Medikus, F.K. (1786) Theodora Speciosa: Ein Neues Pflanzen Geschlecht. Hof- und Akademische Buchhandlung, Mannheim, 116 pp. [https://gallica.bnf.fr/ark:/12148/bpt6k98082x/f1.item]
  91. Mike, T., Lena, S. & Joachim, W.K. (1999) The phylogenetic relationships and evolution of the Canarian laurel forest endemic Ixanthus viscosus (Aiton) Griseb. (Gentianaceae): evidence from matK and ITS sequences, and floral morphology and anatomy. Plant Systematics & Evolution 218: 299–317. https://doi.org/10.1007/BF01089233
  92. Miller, M.A., Pfeiffer, W. & Schwartz, T. (2010) Creating the CIPRES Science Gateway for inference of large phylogenetic trees. In: Proceedings of the Gateway Computing Environments Workshop (GCE). 14 November 2010, New Orleans, pp. 1–8. https://doi.org/10.1109/GCE.2010.5676129
  93. Miller, P. (1768) The Gardener’s Dictionary, ed. 8. Rivington et al., London, 228 pp. https://doi.org/10.5962/bhl.title.541
  94. Moench, C. (1794) Methodus plantas horti botanici et agri Marburgensis: a staminum situ describendi 2. Officina Nova Libraria Academiae, Marburgi Cattorum, 411 pp. https://doi.org/10.5962/bhl.title.304
  95. Mottram, R. (2013) Typification and the application of the name Aloe perfoliata L. The Cactician 1: 1–15. [https://www.crassulaceae.ch/docs/43ab8f4f61de6cf2c3b32ec36701b9e5_Cactician%201%20HQ.pdf]
  96. 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.
  97. Narbona, E., Del Ville, J.C. & Whittall, J.B. (2021) Painting the green canvas: how pigments produce flower colours. The Biochemist 43 (3): 6–12. https://doi.org/10.1042/bio_2021_137
  98. Pillans, N.S. (1933a) Plants, new or noteworthy. South African Gardening and Country Life 23: 167–168.
  99. Pillans, N.S. (1933b) Plants, new or noteworthy. South African Gardening and Country Life 23: 213.
  100. Pillans, N.S. (1934) Plants, new or noteworthy. South African Gardening and Country Life 24: 24–25, 28.
  101. Powell, W., Morgantet, M., Andre, C., McNicol, J.W., Machray, G.C., Doyle, J.J., Tingeyt, S.V. & Rafalski, J.A. (1995) Hypervariable microsatellites provide a general source of polymorphic DNA markers for the chloroplast genome. Current Biology 5 (9): 1023–1029. https://doi.org/10.1016/s0960-9822(95)00206-5
  102. 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. Strelitzia 25. South African National Biodiversity Institute, Pretoria, 668 pp. [http://hdl.handle.net/20.500.12143/260]
  103. Rakotoarisoa, S.E., Klopper, R.R. & Smith, G.F. (2014) A preliminary assessment of the conservation status of the genus Aloe L. in Madagascar. Bradleya 32: 81–91. https://doi.org/10.25223/brad.n32.2014.a1
  104. Ramdhani, S., Barker, N.P. & Baijnath, H. (2009) Rampant non-monophyly of species in Kniphofia Moench (Asphodelaceae) suggests a recent Afromontane radiation. Taxon 58 (1): 1141–1152. https://doi.org/10.1002/tax.584008
  105. Ramdhani, S., Barker, N.P. & Cowling, R.M. (2011) Revisiting monophyly in Haworthia Duval (Asphodelaceae): incongruence, hybridization and contemporary speciation. Taxon 60: 1001–1014. https://doi.org/10.1002/tax.604005
  106. Rauh, W. (1966a) Bemerkenswerte Sukkulenten aus Madagaskar, 19. Neue Aloe-Arten aus Madagaskar. Kakteen und andere Sukkulenten 17: 2–4.
  107. Rauh, W. (1966b) Bemerkenswerte Sukkulenten aus Madagaskar, 19. Neue Aloe-Arten aus Madagaskar. Kakteen und andere Sukkulenten 17: 22–24.
  108. Rauh, W. (2000) Aloe steffaniana Rauh spec. nov., eine neue Art aus Madagascar. Kakteen und andere Sukkulenten 51: 71–74.
  109. Rauh, W. & Petignat, H. (1999) Eine neue Aloe aus Madagascar: Aloe ruggingiana spec. nov. Kakteen und andere Sukkulenten 50: 269–272.
  110. Reynolds, G.W. (1940) Genus Aloe: a new section and a new series. Journal of South African Botany 6: 111–116. [https://archive.org/details/journalofsouthaf06unse/page/110/mode/2up]
  111. Reynolds, G.W. (1950) The Aloes of South Africa. Aloes of South Africa Book Fund, Johannesburg, 520 pp.
  112. Reynolds, G.W. (1966) The Aloes of Tropical Africa and Madagascar. Aloes Book Fund, Mbabane, 537 pp.
  113. Reynolds, T. (1985) The compounds in Aloe leaf exudate: a review. Botanical Journal of the Linnean Society 90 (3): 157–177. https://doi.org/10.1111/j.1095-8339.1985.tb00377.x
  114. Roemer, J.J. & Schultes, J.A. (1829) Systema Vegetabilum 7. Sumtibus J.G. Cottae, Stuttgardt, pp. 631–715. [https://bibdigital.rjb.csic.es/idurl/1/10985]
  115. Ronse De Craene, L.P. & Wanntorp, L. (2011) Chapter 1: Introduction: Establishing the state of the art–the role of morphology in plant systematics. In: Wanntorp, L. & Ronse De Craene, L.P. (Eds.) Flowers on the Tree of Life. Cambridge University Press, Cambridge, pp. 1–7.
  116. Rothmann, S. (2004) Aloes, aristocrats of the Namibian flora. ST Promotions, Swakopmund, pp. 96.
  117. Runemark, H. (1970) The role of small populations for the differentiation in plants. Taxon 19: 196–201. https://doi.org/10.2307/1217954
  118. Salm-Reifferscheid-Dyck, Prince J.F.M.A.H.I. von (1817) Catalogue raisoné des Espèces d’Aloes. Düsseldorf, 72 pp. https://doi.org/10.5962/bhl.title.149682
  119. Salm-Reifferscheid-Dyck, Prince J.F.M.A.H.I. von (1837) Monographia generum Aloes et Mesembryanthemi 2. Henry & Cohen, Düsseldorf & Bonn, 58 tab. https://doi.org/10.5962/bhl.title.153143
  120. Salm-Reifferscheid-Dyck, Prince J.F.M.A.H.I. von (1842) Monographia generum Aloes et Mesembryanthemi 4. Henry & Cohen, Düsseldorf & Bonn, 56 tab. https://doi.org/10.5962/bhl.title.153143
  121. Salm-Reifferscheid-Dyck, Prince J.F.M.A.H.I. von (1849) Monographia generum Aloes et Mesembryanthemi 5. Henry & Cohen, Düsseldorf & Bonn, 54 tab. https://doi.org/10.5962/bhl.title.153143
  122. Salm-Reifferscheid-Dyck, Prince J.F.M.A.H.I. von (1854) Monographia generum Aloes et Mesembryanthemi 6. Henry & Cohen, Düsseldorf & Bonn, 50 tab. https://doi.org/10.5962/bhl.title.153143
  123. Sang, T. (2002) Utility of low-copy nuclear gene sequences in plant phylogenetics. Critical Reviews in Biochemistry & Molecular Biology 37 (3): 121–147. https://doi.org/10.1080/10409230290771474
  124. Sapir, Y., Gallagher, M.K. & Senden, E. (2021) What maintains flower colour variation within populations? Trends in Ecology 36 (6): 507–519. https://doi.org/10.1016/j.tree.2021.01.011
  125. Schneider, S., Roessli, D. & Excoffier, L. (2000) ARLEQUIN ver 2.000: a software for population genetic data analysis. Genetic and Biometry Laboratory, University of Geneva, Switzerland.
  126. Schönland, S. (1907) On some new and some little known species of South African plants belonging to the genera Aloe, Gasteria, Crassula, Cotyledon and Kalanchoe. Records of the Albany Museum 2: 137–155.
  127. Scopoli, J.A. (1783) Fundamenta botanica praelectionibus publicis accommodate. Horto Botanico Ticinensis, Paiva, 192 pp. [https://wellcomecollection.org/works/jctrpg83/items]
  128. Scott Elliot, G.F. (1891) New and little-known Madagascan plants. Journal of the Linnean Society, Botany 29: 1–67. [https://www.biodiversitylibrary.org/item/8386#page/9/mode/1up]
  129. Smith, G.F. (2020) Aloe ×retiefii (Asphodelaceae subfam. Alooideae), a new nothospecies from northeastern South Africa, with A. globuligemma and A. marlothii as parents. Phytotaxa 468 (1): 150–154. https://doi.org/10.11646/phytotaxa.468.1.12
  130. Smith, G.F. (2022) Aloe davyana var. magdae (Asphodelaceae subfam. Alooideae), a distinctive new variety from central-northeastern South Africa. Phytotaxa 536 (3): 261–269. https://doi.org/10.11646/phytotaxa.536.3.6
  131. Smith, G.F. & Figueiredo, E. (2015) Garden aloes. Growing and breeding cultivars and hybrids. Jacana Media (Pty) Ltd, Auckland Park, Johannesburg, 193 pp.
  132. Smith, G.F. & Figueiredo, E. (2019) Aloe ×gemmelliae (Asphodelaceae subfam. Alooideae), a new natural hybrid between A. broomii and A. grandidentata from the southwestern Free State province, South Africa. Phytotaxa 423 (3): 182–186. https://doi.org/10.11646/phytotaxa.423.3.6
  133. Smith, G.F. & Figueiredo, E. (2022) Aloe hankeyi (Asphodelaceae subfam. Alooideae; Aloe sect. Leptoaloe), a new species from northern South Africa. Phytotaxa 549 (1): 122–126. https://doi.org/10.11646/phytotaxa.549.1.12
  134. Smith, G.F. & Klopper, R.R. (2021a) Aloe ×selmarii (Asphodelaceae subfam. Alooideae), a new nothospecies from South Africa, with A. davyana var. davyana and A. parvibracteata as parents. Phytotaxa 521 (4): 289–300. https://doi.org/10.11646/phytotaxa.521.4.4
  135. Smith, G.F. & Klopper, R.R. (2021b) Reinstatement of Aloe labiaflava (Asphodelaceae subfam. Alooideae), a distinctive species of maculate aloe endemic to the western Mpumalanga province of South Africa. Phytotaxa 512 (3): 179–189. https://doi.org/10.11646/phytotaxa.512.3.5
  136. Smith, G.F. & Klopper, R.R. (2022a) Reinstatement of Aloe longibracteata (Asphodelaceae subfam. Alooideae), a maculate aloe from northeastern South Africa. Phytotaxa 568 (2): 291–300. https://doi.org/10.11646/phytotaxa.568.2.4
  137. Smith, G.F. & Klopper, R.R. (2022b) Aloe immaculata and A. affinis (Asphodelaceae subfam. Alooideae), two endemics from northern and eastern South Africa, are different maculate aloe species. Phytotaxa 571 (3): 291–300. https://doi.org/10.11646/phytotaxa.571.3.3
  138. Smith, G.F. & Lautenschlaeger, T. (2021) Aloe uigensis (Asphodelaceae subfam. Alooideae), a new species from northwestern Angola. Phytotaxa 521 (3): 227–231. https://doi.org/10.11646/phytotaxa.521.3.8
  139. Smith, G.F. & Van Wyk, B-E. (1996) Aloe succotrina and Reynolds’ book on the aloes of South Africa. Aloe 33: 57–58.
  140. Smith, G.F., Klopper, R.R. & Crouch, N.R. (2008) Aloe arborescens (Asphodelaceae: Alooideae) and CITES. Haseltonia 14: 189–198. https://doi.org/10.2985/1070-0048-14.1.189
  141. Smith, G.F., Meyer, N.L. & Glen, H.F. (1994) Little-known generic names in the family Aloaceae. South African Journal of Science 90 (8 & 9): 489–490.
  142. Smith, G.F., Figueiredo, E., Klopper, R.R., Campbell, E.E. & Martin, K. (2022) Aloiampelos tenuior var. ernstii, a new orange-flowered variety of rambling aloe (Asphodelaceae subfam. Alooideae). Phytotaxa 571 (1): 91–96. https://doi.org/10.11646/phytotaxa.571.1.8
  143. Smith, G.F., Figueiredo, E., Klopper, R.R. & Crouch, N.R. (2012a) Summer-flowering species of maculate Aloe L. (Asphodelaceae: Alooideae) in the Aloe zebrina-complex from South Africa: reinstatement of four names, and description of A. braamvanwykii Gideon F.Sm. & Figueiredo. Bradleya 30: 155–166. https://doi.org/10.25223/brad.n30.2012.a19
  144. Smith, G.F., Klopper, R.R., Figueiredo, E. & Crouch, N.R. (2012b) Aspects of the taxonomy of Aloe arborescens Mill. (Asphodelaceae: Alooideae). Bradleya 30: 127–137. https://doi.org/10.25223/brad.n30.2012.a15
  145. Smith, G.F., Klopper, R.R., Crouch, N.R. & Figueiredo, E. (2016) Reinstatement of Aloe candelabrum A.Berger (Asphodelaceae: Alooideae), a tree-like aloe of KwaZulu-Natal province, South Africa. Bradleya 34: 59–69. https://doi.org/10.25223/brad.n34.2016.a21
  146. Smith, G.F., Klopper, R.R., Crouch, N.R. & Figueiredo, E. (2020) Reinstatement of Aloe davyana (Asphodelaceae subfam. Alooideae), a winter-flowering species endemic to central-northeastern South African aloe. Phytotaxa 475 (3): 201–208. https://doi.org/10.11646/phytotaxa.475.3.4
  147. Smith, G.F., Klopper, R.R., Crouch, N.R. & Figueiredo, E. (2021) Reinstatement of Aloe davyana var. subolifera (Asphodelaceae subfam. Alooideae), a distinctive variety of an endemic South African aloe. Phytotaxa 482 (2): 208–212. https://doi.org/10.11646/phytotaxa.482.2.9
  148. Stamatakis, A. (2014) RAxML Version 8: A tool for phylogenetic analysis and post-analysis of large phylogenies. Bioinformatics 30: 1312–1313. https://doi.org/10.1093/bioinformatics/btu033
  149. Steyn, E.M.A., Smith, G.F., Nilsson, S. & Grafström, E. (1998) Pollen morphology in Aloe (Aloaceae). Grana 37 (1): 23–27. https://doi.org/10.1080/00173139809362635
  150. Symes, C.T. (2012) Seed dispersal and seed banks in Aloe marlothii (Asphodelaceae). South African Journal of Botany 78: 276–280. https://doi.org/10.1016/j.sajb.2011.06.008
  151. Thiers, B. (2023+ [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/ih (accessed July 2023).
  152. Thunberg, C. (1794) Prodromus Plantarum Capensium: quas in promontorio Bonæ Spei Africes, annis 1772–1775, Vol. 1. J. Edman, Upsala, p. 60. https://doi.org/10.5962/bhl.title.84
  153. Treutlein, J., Smith, G.F., Van Wyk, B-E. & Wink, M. (2003a) Phylogenetic relationships in Asphodelaceae (subfamily Alooideae) inferred from chloroplast DNA sequences (rbcL, matK) and from genomic fingerprinting (ISSR). Taxon 52 (2): 193–207. https://doi.org/10.2307/3647487
  154. Treutlein, J., Smith, G.F., Van Wyk, B-E. & Wink, M. (2003b) Evidence for the polyphyly of Haworthia (Asphodelaceae subfamily Alooideae; Asparagales) inferred from nucleotide sequences of rbcL, matK, ITS1 and genomic fingerprinting with ISSR-PCR. Plant Biology 5 (5): 513–521. https://doi.org/10.1055/s-2003-44793
  155. 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. (2018) International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017. Koeltz Botanical Books, Glashütten. [Regnum Vegetabile 159: 1–254]. https://doi.org/10.12705/Code.2018
  156. Van Jaarsveld, E.J. (2010) Aloe tongaensis, a new species from Tongaland, KwaZulu-Natal (South Africa), and a new sectional arrangement of the tree aloes. Aloe 47: 64–71.
  157. Van Wyk, A.E. & Smith, G.F. (2001) Regions of floristic endemism in southern Africa. A review with emphasis on succulents. Umdaus Press, Hatfield, 199 pp.
  158. Van Wyk, B-E. & Smith, G.F. (1996) Guide to the aloes of South Africa. Briza, Pretoria, 302 pp.
  159. Van Wyk, B-E. & Smith, G.F. (2014) Guide to the aloes of South Africa, 3rd edn. Briza, Pretoria, 376 pp.
  160. Van Wyk, B-E., Yenesew, A. & Dagne, E. (1995) Chemotaxonomic survey of anthraquinones and pre-anthraquinones in roots of Aloe species. Biochemical Systematics & Evolution 23 (3): 267–275. https://doi.org/10.1016/0305-1978(94)00095-X
  161. Viljoen, A. (1999) A chemotaxonomic study of the phenolic leaf compounds in the genus Aloe. Ph.D. thesis, Rand Afrikaans University, Johannesburg, 634 pp. [http://hdl.handle.net/10210/6612]
  162. Viljoen, A.M. & Van Wyk, B-E. (1999) The chemotaxonomic value of two cinnamoyl chromones, aloeresin E and F, in Aloe (Aloaceae). Taxon 48 (4): 747–754. https://doi.org/10.2307/1223645
  163. Viljoen, A.M., Van Wyk, B-E. & Van Heerden, F.R. (1998) Distribution and chemotaxonomic significance of flavonoids in Aloe (Asphodelaceae). Plant Systematics & Evolution 211: 31–42. https://doi.org/10.1007/BF00984910
  164. Walker, C.C., Klopper, R.R., Smith, G.F. & Condy, G. (2015) Aloe succotrina. Flowering Plants of Africa 64: 26–40, t.2304.
  165. Weiss, M.R. (1991) Floral colour changes as cues for pollinators. Nature 354: 227–229.
  166. Weiss, M.R. & Lamont, B.B. (1997) Floral color change and insect pollination: a dynamic relationship. Israel Journal of Plant Sciences 45 (2–3): 185–199. http://dx.doi.org/10.1080/07929978.1997.10676683
  167. Weston, R. (1770) Botanicus universalis et hortulanus, Vol. 1. Wheble & Etherington, Bell, Riley, 384 pp.
  168. Wheeler, Q.D. (2008) Chapter 1: Introductory – toward the new taxonomy. In: Wheeler, Q.D. (Ed.) The new taxonomy, The Systematics Association Special Volume Series 76. CRC Press, New York, pp. 1–17.
  169. White, T.J., Bruns, T., Lee, S. & Taylor, J. (1990) Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. In: Innis, M., Gelfand, D., Sninsky, J. & White, T. (Eds.) PCR protocols: a guide to methods and applications. Academic Press, San Diego, pp. 315–322.
  170. Wijnands, D.O. (1983) The botany of the Commelins. A.A. Balkema, Rotterdam, 232 pp.
  171. Williamson, G. (2000) Richtersveld. The enchanted wilderness. Umdaus Press, Hatfield, 258 pp.