South African Journal of Botany 72 (2006) 205 – 210 www.elsevier.com/locate/sajb

The endemic flora of the ,

N.A. Helme a,*, T.H. Trinder-Smith b

a Nick Helme Botanical Surveys, PO Box 22652, Scarborough 7975, South Africa b Bolus Herbarium, Department of Botany, University of , Private Bag, Rondebosch 7700, South Africa

Received 27 June 2005; accepted 13 July 2005

Abstract

The Cape Peninsula is a well known area of exceptional diversity and endemism within the Cape Floristic Region, but an accurate and complete listing of the endemic seed plant species has been lacking. Here, we present a list of the 158 species and 3 subspecies that are currently regarded as Cape Peninsula endemics, with discussion on the profile of the endemic flora, plant hotspots within the area, and conservation issues. Endemics constitute 7% of the total Peninsula flora. 76% of the endemic species fall within only 10 families, with being the with the greatest number of endemic species on the Peninsula (39). The Peninsula is identified as a centre of endemism for Roella, Tetraria, Serruria, and Muraltia. Many families are notably under-represented in terms of endemic species on the Peninsula, including Geraniaceae, Oxalidaceae, Thymelaeaceae, Apiaceae, Hyacinthaceae, Poaceae, Rhamnaceae, Rutaceae, Orchidaceae, and Asteraceae. 62% of the endemics are shrubs or dwarf shrubs. 41% of the endemics are currently Red Data Book listed, but the National Park conserves a large percentage of the montane habitat, as well as significant lowland habitat in the extreme south. D 2005 SAAB. Published by Elsevier B.V.

Keywords: South Africa; Cape Peninsula; Cape floristic region; Endemics; Floristics; Phytogeography; Plant diversity

1. Introduction Muizenberg, and thus includes a small part of the western edge of the area known as the Cape Flats (Fig. 1). The area is The Cape Peninsula is a well-known area of exceptional defined by the presence of the Cape Peninsula mountain chain, plant diversity and endemism (Trinder-Smith et al., 1996a; extending from Signal Hill and Lion’s Head in the north to Pauw and Johnson, 1999) within the southwestern core of the Cape Point in the south. The total land area is approximately Cape Floristic Region (CFR) of southern Africa. The CFR is an 471 km2 (47 100 ha), and some 24000 ha is now formally or area of high species diversity and endemism (Van Wyk and contractually conserved within the Table Mountain National Smith, 2001), and the area experiences winter rain and summer Park, which includes 80% of the actual mountain chain. drought, except at high elevations. Trinder-Smith et al. Studies of this nature are complicated by ongoing taxo- (1996a,b) concluded that a total of 90 taxa (including two nomic studies, especially in the genera Erica and Cliffortia, infra-specific taxa) could be regarded as Cape Peninsula and in the family Aizoaceae, and largely follows endemics and analysed the makeup of this flora in terms of Goldblatt and Manning (2000), with reference to specialists its threat status, life form, and various biological traits where appropriate. (resprouting vs. reseeding, seed dispersal), but did not publish Currently about 2285 species are known to be the list of taxa concerned. Here we present an updated and indigenous to the Cape Peninsula (Trinder-Smith et al., 1996a), significantly enlarged list of the endemic angiosperm flora of which is in itself a remarkable statistic, as it means that the the Cape Peninsula (algae, ferns, and mosses are thus excluded Peninsula has the greatest concentration of plant species (per from this list). No gymnosperms are endemic to this area. unit area) within the CFR (Trinder-Smith et al., 1996a,b). Our For purposes of our study the Cape Peninsula is defined as revised analysis shows that 158 species (plus 3 subspecies) are the area west of a line connecting Paarden Island to endemic (Table 1), which is 7.0% of the total flora. This figure is high for a continental landmass (Davis et al., 1997), but is * Corresponding author. substantially exceeded by many island floras, such as Juan E-mail address: [email protected] (N.A. Helme). Fernandez, some 600 km west of Chile at 33- south, with 127

0254-6299/$ - see front matter D 2005 SAAB. Published by Elsevier B.V. doi:10.1016/j.sajb.2005.07.004 206 N.A. Helme, T.H. Trinder-Smith / South African Journal of Botany 72 (2006) 205–210

0.400.4 0.8 1.2 1.6 2 2.4 2.8 3.2 3.6 4.0 4.4 4.8 5.2 5.6 6.0 6.4 6.8 7.2 7.6 8.0 8.4 8.8 9.2 9.6 Kilometer s

N Milnerton Lagoon

Green Point #

# Paarde ne iland Signal Hill $ Cape Town Sea Point # City Bowl

$ Lion's Head

Camps Bay #

$ Devil's Peak # Rondebosch Ta ble Mo Common untain s le st o p A e lv e w T e Kenilworth h T Racecourse # 34° 00’ S

Llandudno Bay #

$ Vlakkenberg

$ Skoorsteenkop $ Karbonkelberg # Hout Bay

# Retreat Hangberg $ Constantiaberg

$ Noordhoek Peak

St P ee la nb ##Lakeside te er Sandvlei $ Chapman's Peak au g

$ HoÎr -Steenbergpiek Kalk Bay $ Muizenberg Peak Plateau

Chapman's Bay $ Kalkbaaiberg # Muizenberg

# Kalk Bay

# Fishhoek Kommetjie # $ 15’ E Rooikrans ° 30’ E ° 18

$ Slangkop 18

# Simon's Town

$ Simonsberg K lav Va er lle y $ Swartkop $ Klaasjagersberg

# Miller's Point

34° 15’ S $ Wolfkop

# Olifantsbos

Smitswinkel Bay $ Rooihoogte CAPE OF GOOD HOPE NATURE RESERVE

$ Paulsberg

>1000m 800 - 1000m 600 - 800m 400 - 600m 200 - 400m Vasco da Gama Peak 100m $ 40m # Cape Point

Fig. 1. Map of the study area, indicating topography and some of the key areas mentioned in the text. N.A. Helme, T.H. Trinder-Smith / South African Journal of Botany 72 (2006) 205–210 207

Table 1 Table 1 (continued) List of the 161 endemic Angiosperm taxa of the Cape Peninsula, South Africa Family Species Notes Family Species Notes Erica fontana Aizoaceae Erepsia forficata Erica haematocodon Lampranthus multiradiatus Erica halicacaba Lampranthus promontorii Erica heleogena Lampranthus tenuifolius Erica limosa Ruschia rubricaulis Erica margaritacea Ruschia promontorii Erica marifolia Amaryllidaceae Gethyllis kaapensis Erica mollis Asphodelaceae Aloe commixta Erica nevillei Asteraceae Anaxeton arborescens Erica oxycoccifolia Cotula myriophylloides Erica paludicola Gerbera wrightii Erica physodes Helichrysum fruticans Erica pilulifera Helichrysum grandiflorum Erica planifolia Metalasia compacta Erica pyramidalis Extinct Metalasia divergens ssp. fusca Erica pyxidiflora Osmitopsis dentata Erica quadrisulcata Stoebe rosea Erica salteri Senecio verbascifolius Erica sociorum Brassicaceae Heliophila cinerea Erica subcapitata Heliophila promontorii Erica thimifolia Heliophila tabularis Probably extinct Erica turgida Lepidium capense Probably extinct; Erica urna-viridis possibly not a Erica velitaris Probably a hybrid distinct species Erica verticillata Extinct in the wild Bruniaceae Staavia dodii Fabaceae Aspalathus barbata Staavia glutinosa Aspalathus borboniifolia Lobelia boivinii Aspalathus capensis Lobelia eckloniana Aspalathus capitata Prismatocarpus nitidus Aspalathus chenopoda ssp. chenopoda Roella amplexicaulis Aspalathus incurva Roella decurrens Aspalathus variegata Extinct Roella goodiana Cyclopia galioides Roella recurvata Cyclopia latifolia Roella squarrosa Indigofera candolleana Roella triflora Indigofera complanata Wahlenbergia pyrophila Indigofera filiformis Colchicaceae Wurmbea hiemalis Indigofera mauritanica Cyperaceae Eleocharis lepta Extinct Indigofera sp. nov. aff gracilis Ficinia anceps Lebeckia macowanii Probably extinct Ficinia fastigiata Liparia graminifolia Extinct Ficinia micrantha Liparia parva Isolepis pusilla Liparia laevigata Isolepis bulbiferus Psoralea glaucina Tetraria autumnalis Hyacinthaceae Lachenalia capensis Tetraria graminifolia Aristea pauciflora Tetraria paludosa Bobartia gladiata ssp. major Tetraria variabilis Geissorhiza bonaspei Trianoptiles solitaria Geissorhiza tabularis Dipsacaceae Scabiosa africana Gladiolus aureus Droseraceae Drosera cuneifolia Gladiolus bonaspei Ericaceae Erica abietina Gladiolus monticola Erica amoena Gladiolus vigilans Erica annectens aristata Erica baccans Watsonia tabularis Erica capensis Malvaceae Hermannia micrantha Erica caterviflora Probably extinct Menyanthaceae Villarsia goldblattiana Erica clavisepala Molluginaceae Hypertelis trachysperma Erica conica Myricaceae Morella diversifolia Erica cyrilliflora Orchidaceae Disa ecalcarata Erica depressa Disa nubigena Erica diosmifolia Pterygodium connivens Erica eburnea Penaeaceae Brachysiphon fucatus Erica empetrina Poaceae Helictotrichon quinquesetum Probably extinct Erica fairii (continued on next page) 208 N.A. Helme, T.H. Trinder-Smith / South African Journal of Botany 72 (2006) 205–210

Table 1 (continued) Table 2 Family Species Notes Ten largest families of Cape Peninsula endemics Family Number of endemic species Muraltia curvipetala Muraltia demissa Ericaceae 39 Muraltia acipetala Fabaceae 19 Muraltia brachypetala Cyperaceae 11 Muraltia comptonii Asteraceae 10 Muraltia diabolica Campanulaceae 10 Muraltia mixta Iridaceae 10 Muraltia orbicularis Polygalaceae 10 Muraltia pageae Proteaceae 10 Muraltia stipulacea Restionaceae 7 Proteaceae Leucadendron floridum Aizoaceae 6 Leucadendron macowanii Leucadendron grandiflorum Extinct Leucadendron strobilinum families are notably under-represented in terms of endemic Mimetes fimbriifolius species on the Peninsula, including Geraniaceae (155/33/0), Serruria decumbens Serruria collina Oxalidaceae (120/33/0), Thymelaeaceae (124/32/0), Apiaceae Serruria glomerata (72/28/0), Hyacinthaceae (192/41/1), Poaceae (207/144/1), Serruria hirsuta Rhamnaceae (137/25/1), Rutaceae (237/22/2), Orchidaceae Serruria villosa (227/118/3), and Asteraceae (1036/286/10). Restionaceae Anthochortus capensis The representation of endemic species within the Cape Elegia intermedia Probably not a distinct species Peninsula is heavily skewed in favour of a limited number of Calopsis gracilis genera, with only six genera accounting for 45% of the Restio communis endemic species (Table 3). Erica is a special case, as this Thamnochortus levynsiae enormous genus is species-rich in most mesic areas with Thamnochortus nutans significant topography, with many endemics in such areas. Willdenowia affinis Probably extinct Rhamnaceae Phylica schlechteri Probably extinct Only 6% of the CFR Erica species are endemic to the Cape Rosaceae Cliffortia theodori-friesii Peninsula, although in terms of numbers of endemic species Rutaceae Agathosma lanceolata this genus is by far the largest (39 endemics). This contrasts Agathosma pulchella with the genus Roella, with a remarkable 31% of this genus Scrophulariaceae Microdon nitidus endemic to the Peninsula, and the area can thus be regarded as Nemesia micrantha Probably extinct Polycarena silenoides a major centre of endemism for Roella. The genera Muraltia, Pseudoselago peninsulae Tetraria, and Serruria all have T10% of their total species endemic to the Peninsula, which is likewise identified as a centre of endemism for these genera. endemic vascular plant species out of 210 (64%), on 100 km2 There is a significant under-representation of endemic (Davis et al., 1995), and the Bonin Islands of Japan (23- north), species in certain large genera, such as Agathosma, Phylica, with 150 endemic species out of 440 (34%), on only 73 km2 Aspalathus, Pelargonium, Oxalis, Cliffortia, Moraea, Senecio, (Davis et al., 1995). McDonald and Cowling (1995) recorded Thesium, and Crassula. In all these cases, less than 2% of the 160 endemic species in the Langeberg mountains of the total number of species in the genus is endemic to the southern Cape, an area 3.7 times the size of the Cape Peninsula. Peninsula. Although many of these genera are well represented Comparison with other areas in the CFR is hampered by a lack on the Peninsula (relatively species rich), their centres of of analysis of the endemic flora component. endemism lie elsewhere, (Salter, 1944; Tolken, 1985; Gold- blatt, 1986; Dahlgren, 1988; Goldblatt and Manning, 2000), 1.1. A profile of the endemic flora

The 158 endemic species and three subspecies are distrib- uted among 27 families (Table 1). The ten largest families Table 3 Nine largest genera of Cape Peninsula endemics account for 122 of the endemic species on the Cape Peninsula (Table 2). Genus Number of endemic species Families that are significantly over-represented in terms of Erica (Ericaceae) 39 the CFR flora as a whole include Ericaceae (658/131/39)1, Muraltia (Polygalaceae) 10 Aspalathus (Fabaceae) 7 Campanulaceae (184/72/10), Cyperaceae (206/144/11), Poly- Roella (Campanulaceae) 6 galaceae (141/33/10), and Proteaceae (330/49/10). Many Indigofera (Fabaceae) 5 Serruria (Proteaceae) 5 Gladiolus (Iridaceae) 4 1 Tetraria (Cyperaceae) 4 (No. of species in the CFR /No. of species on the Peninsula /No. of Peninsula endemics). Leucadendron (Proteaceae) 4 N.A. Helme, T.H. Trinder-Smith / South African Journal of Botany 72 (2006) 205–210 209

Table 4 Holland mountains between Rooiels and Kleinmond and The growth form composition of the 158 endemic plant species and 3 extends as far east as the Kleinriver mountains near Hermanus subspecies on the Cape Peninsula (Bradshaw, unpublished data; and pers. obs.), thus providing Growth form Percentage strong evidence that these areas were once botanically linked Shrubs/dwarf shrubs 62 when sea levels were lower. There is also a notable link Graminoids 12 between the flora of Table Mountain and the higher mountains Geophytes 10 Succulents 5 above Jonkershoek, just east of Stellenbosch, where seven Annuals 5 species are shared (Bradshaw, unpublished data), including Herbs/Forbs 5 Gladiolus pappei, recently confirmed from the latter area. (Manning - pers. comm.). This link is perhaps maintained by high rainfall and summer cloud incidence in these areas, which and the Peninsula is thus not a critical area for the conservation are separated by 60 km of intervening Cape Flats (mostly <70 of species diversity within these genera. masl), an area certain to have been under the sea during the The majority of the Peninsula endemics are shrubs or dwarf early Pliocene (4 Mybp), when sea levels were about 100 m shrubs (62%), with graminoids (primarily Restionaceae) (12%) higher than present (Hendey, 1983). and geophytes (10%) making up the next largest groups (Table 4). Graminoids are over-represented in terms of the CFR as a 1.3. Conservation issues whole, while geophytes are underrepresented (Goldblatt and Manning, 2000). This is likely to be a reflection of the At least 66 (41%) of the Peninsula endemic species are generally more mesic nature of the Peninsula. currently Red Data Book listed (Hilton Taylor, 1996)as threatened in some way, and are thus of immediate conserva- 1.2. Hotspots within the Peninsula tion concern. Many are extremely localised, and in some cases are known from a single population of fewer than fifty , Distribution of endemic plant species on the Peninsula is not and these are obviously in imminent danger of extinction. Six random, and all areas are not equally rich in localised species. Peninsula endemics are already confirmed extinct, with only There is a strong correlation between the distributions of one of these in cultivation (Erica verticillata). A further eight endemic animals (primarily invertebrates) and endemic plants species are likely to be extinct, as they have not been collected on the Peninsula, and this is especially true on Table Mountain for at least thirty years, and in some cases for over a century. itself (Picker and Samways, 1996). Most of the extinct species are lowland plants whose habitats Concentrations of endemic plants occur on the few remaining have now been transformed by agriculture and urbanisation, examples of acid Sand within the Peninsula, notably and the main ‘‘extinction hotspot’’ is the western edge of the within the conservation area at Kenilworth Racecourse and at Cape Flats (incorporating acid sands, shales, and granites), Zandvlei and Rondevlei Municipal Reserves (the latter just from Paarden Island to Kenilworth and Wynberg. There is one outside the study area). This concentration is probably artificial, extinct species from the Hout Bay valley, one from the Fish in that once more widespread Cape Flats species are now Hoek valley, and possibly two from the City Bowl area. restricted to remnant conservation areas (Trinder-Smith et al., The creation of the Table Mountain National Park is 1996b). Other notable hotspots for endemics include the upper extremely fortuitous given the global conservation significance parts of Table Mountain itself, the Karbonkelberg, the upper of this area, and the future would seem to be relatively bright slopes of Constantiaberg and Noordhoek Peak, the Kalk Bay for this area. The key concerns for the endemic species in the plateau, Rooikrans hill above Capri, the Klawer valley wetlands Park are inappropriate fire regimes, alien invasive species, above Simonstown, the Swartkop mountains above Millers random events such as disease and plant collecting (for the Point, and most of the Cape of Good Hope Nature Reserve area rarest species), and more difficult to detect — the long term in the far south. The latter area supports eleven strict endemics, loss of genetic diversity and key pollinators. Urbanisation with a further species restricted to the area immediately adjacent. pressures and lack of motivated and skilled management On the Bonteberg south of Scarborough we have recorded up to continue to be a major threat to the lowland areas outside the eight Peninsula endemics growing within a 30 m2 area. National Park. Key habitats for Peninsula endemics include seepage areas and wetlands at upper (Trinder-Smith et al., 1996a) and lower Acknowledgements elevations; steep, moist south or southeast facing slopes, many of which get summer moisture in the form of southeast cloud; Various specialists have made available their information, and lower rocky, sandstone slopes in the southern Peninsula. and the staff of the Compton Herbarium, Kirstenbosch, are Relatively few species seem to be endemic to the richer shale thanked for access to collections therein. and granite soils that are most prevalent on the lower slopes of the northern part of the Peninsula, perhaps because these References habitats are better represented elsewhere further east. Thirty nine species occur only on the Peninsula and then Dahlgren, R., 1988. Aspalathus. Flora of Southern Africa 16 Part 3 Fascicle 6. again in an area which includes the southern coastal Hottentots Botanical Research Institute, Pretoria. 210 N.A. Helme, T.H. Trinder-Smith / South African Journal of Botany 72 (2006) 205–210

Davis, S.D., Heywood, V.H., Hamilton, A.C., 1995. Centres of plant diversity. Pauw, A., Johnson, S., 1999. Table Mountain: A Natural History. Fernwood A Guide and Strategy for their Conservation, vol. 2. IUCN, Cambridge, Press, Cape Town. UK, pp. 565–568. ISBN: 2-8317-0198-8. Picker, M.D., Samways, M.J., 1996. Faunal diversity and endemicity of the Davis, S.D., Heywood, V.H., Herrera-MacBryde, O., Villa-Lobos, J., Cape Peninsula, South Africa—a first assessment. Biodiversity and Hamilton, A.C., 1997. Centres of plant diversity. A Guide and Strategy Conservation 5, 591–606. for their Conservation, vol. 3. IUCN, Cambridge, UK, pp. 63–96. ISBN: 2- Salter, T.M., 1944. The genus Oxalis in South Africa: a taxonomic revision. 8317-0199-6. Journal of South African Botany. Supplementary 1. Goldblatt P., 1986. The of southern Africa. National Botanic Gardens, Tolken, H.R., 1985. Crassulaceae. Flora of Southern Africa, vol. 14. Botanical Pretoria, in association with Missouri Botanical Garden, USA. Research Institute, Pretoria. Goldblatt P., Manning J.C., 2000. Cape Plants. A conspectus of the Cape flora Trinder-Smith, T.H., Cowling, R.M., Linder, H.P., 1996a. Profiling a besieged of South Africa. Strelitzia 9. National Botanical Institute and Missouri flora: endemic and threatened plants of the Cape Peninsula, South Africa. Botanical Garden Press. Biodiversity and Conservation 5, 575–589. Hendey, Q.B., 1983. Cenozoic geology and paleogeography of the Fynbos Trinder-Smith, T.H., Lombard, A.T., Picker, M.D., 1996b. Reserve scenarios Region. In: Deacon, H., Hendey, Q., Lambrechts, J. (Eds.), Fynbos for the Cape Peninsula: high-, middle- and low-road options for conserving Paleoecology: A Preliminary Synthesis, SANSP report, vol. 75. CSIR, the remaining biodiversity. Biodiversity and Conservation 5, 649–669. Pretoria, pp. 35–60. Van Wyk, A.E., Smith, G.F., 2001. Regions of Floristic Endemism in Southern Hilton Taylor, C., 1996. Red data list of southern African plants. Strelitzia, Africa. Umdaus Press, Hatfield. vol. 4. National Botanical Institute, Pretoria. McDonald, D.J., Cowling, R.M., 1995. Towards a profile of an endemic mountain fynbos flora: implications for conservation. Biological Conser- vation 72, 1–12.