Aloe succotrina Weston (1770: 5)

Klopper, Ronell R., Grace, Olwen M., Klopper, Arrie W., Smith, Gideon F. & Van, Abraham E., 2023, A taxonomic revision of Aloe sect. Purpurascentes (Asphodelaceae subfam. Alooideae), Phytotaxa 628 (1), pp. 1921-1935 : 1921-1935

5. Aloe succotrina Weston (1770: 5) ( Fig. 16 )

Homotypic synonyms:— Aloe succotrina Allioni (1773: 65) , nom. superfl.; Aloe succotrina Lamarck (1783: 85) , nom. illegit.; Aloe perfoliata var. succotrina (Lam.) Aiton (1789: 466) . Type:— A. succotrina , angustifolia spinosa, flore purpureo, J. Commelin, Horti medici Amstelaedamensis 1: 91, t. 48 (1697) (Lectotype!, designated by Wijnands 1983: 126).

Epitype (designated by Guglielmone et al. 2009: 180):— SOUTH AFRICA, Western Cape: Boulder field near Window Gorge, above Newlands , July 1905; R . Marloth 3967 (epitype PRE!) .

Synonyms:— Aloe perfoliata var. ξ Linnaeus (1753: 320). Type:—not cited.

Aloe soccotrina Garsault (1764 : pl. 102), nom. inval. Type:—not cited.

Aloe vera Miller (1768: 15) , non ( Linnaeus 1753: 320) Burman (1768: 83), nom. illegit. Type:—not cited.

Aloe perfoliata var. purpurascens Aiton (1789: 466) ; A. socotrina β purpurascens (Aiton) Ker Gawler (1812 : t.1474), nom. inval.; Aloe purpurascens (Aiton) Haworth (1804: 20) . Type:—not cited.

Aloe sinuata Thunberg (1794: 61) . Type:—not cited.

Aloe soccotrina De Candolle (1801 : t.85). Type:—not cited.

Aloe soccotorina Schult. & Schult.f. in Roemer & Schultes (1829: 701), nom. inval. Type:—not cited.

Aloe succotrina var. saxigena Berger (1908: 283) . Type:— SOUTH AFRICA. Western Cape: Steenbras River Mouth, H.W.R. Marloth 4357 (holotype B†) [It was confirmed that this specimen is no longer extant at Herb. B (J. Paule, pers. comm., July 2023)].

Description:— Caulescent or sometimes acaulescent plants, forming dense groups. Stem short or up to 2 m long, 10– 15 cm diameter, simple or dichotomously branched, erect or procumbent, with persistent dried leaves; rosettes solitary or usually in dense large groups. Leaves densely rosulate, erectly spreading, dull green to grey-green, obscurely lineate, sometimes with few white spots, lanceolate-attenuate, 25–50 cm long, 5.5–10.0 cm wide at base; margin with firm, deltoid, white teeth, 2–4 mm long, 5–10 mm apart; exudate honey-coloured, drying purple. Inflorescence single or sometimes 2 simultaneously or consecutively, 0.75–1.00 m high, arcuate-erect, mostly simple, rarely 2-branched from around middle or below. Peduncle 1.0– 1.5 cm wide and plano-convex below, terete upwards, reddish green to brown; with many sterile bracts, ovate-acute, 17–25(–33) mm long, 8–15(–23) mm wide, thin, rather scarious, purplish, many-nerved. Raceme cylindric-acuminate, 21–37 cm long, erect, rather dense; buds erect to spreading, flowers nodding to pendent when open, buds partly obscured by large imbricate bracts. Floral bracts broadly lanceolate, 16–22(–29) mm long, 6–10 mm wide, pinkish green, turning purplish, thin, scarious, many-nerved. Pedicels 20–33(–38) mm long, yellowish green to pinkish or purplish green. Flowers: perianth glossy red to reddish salmon, green-tipped, (25–) 30–40 mm long, 6–8 mm across ovary, not narrowed above ovary, slightly widening to 7–9 mm toward middle, slightly narrowing to 6–7 mm towards wide-open mouth, cylindric-trigonous; outer segments free to base, tips slightly spreading; stamens with pale lemon, filiform flattened filaments, exserted 4–8 mm; ovary 7–8 mm long, 2–3 mm diameter, green; style yellow, exserted 4–8 mm.

Diagnostic characters:— Aloe succotrina is distinguished by its erect, dull grey-green leaves with white marginal teeth and leaf exudate that dries purple. Inflorescences are up to 1 m long, with fairly large purplish bracts. Flowers are red and 30–40 mm long.

Distribution:— Restricted to mountain slopes from the Cape Peninsula to Hermanus, Western Cape, South Africa. Confined to mountain Fynbos on Table Mountain Sandstone.

Habitat:— Mountain Fynbos on Table Mountain Sandstone on steep cliffs and rocky slopes. High winter rainfall, generally close to the sea.

Elevation:— up to 600 m

Flowering time:— July–August

Etymology:— Refers to either the plant being thought to be the source of the drug socotrine aloes and originating from Socotra, however, it grows wild only in the extreme southwestern part of the Western Cape province of South Africa, or to the compound word meaning ‘succus’ (sap), ‘citrinus’ (lemon-yellow). Even though the latter suggests that the leaf exudate turns yellow when it dries ( Reynolds 1950), the juice that dries purple is characteristic of A. succotrina .

General notes:— This is a very variable species. Plants are either solitary with short, simple or branched erect stems, or where conditions are favourable, plants form large dense groups. The largest forms have stems of 1–2 m long that are dichotomously branched and form a large canopy of many rosettes ( Reynolds 1950, Smith & Van Wyk 1996).

Aloe succotrina have a confused history and wrong synonymy that is rivalled by no other aloe. This is mostly due to early authors wrongly assuming that this plant is from the Island of Socotra ( Reynolds 1950).

Plants received by Commelin flowered in 1689 and 1690 in Amsterdam and it was the first South African aloe to be grown in Europe. It is thus surprising that Aloe succotrina is not among the aloes grown at the Dutch East India Company’s Garden in Cape Town when Oldenland was Superintendent there in 1695 ( Reynolds 1950).

Additional specimens examined:— SOUTH AFRICA. Western Cape: Cape Town , 30 September 1921, J. Elffers PRE 38405 ( PRE); From the Camps Bay Road, Unknown s.n. ( NBG). Table Mountain , 28 August 1905, s. coll. ( GRA); Between Devil’s Peak and Kirstenbosch , 17 September 1928, J.B. Gillett 501 ( NBG). Kirstenbosch National Botanical Garden , on contour path on Table Mountain, 9 July 2010, R.R. Klopper & A.W. Klopper 328, 329 & 330 ( NBGgmc, PREgmc). Kirstenbosch, Fernwood Buttress , 10 June 1943, E. Wasserfall s.n. ( NBG). Table Mt., Kirstenbosch , 15 May 1955, J.P. Stokoe s.n. ( SAM); June 1913, L. Bolus 24298 ( BOL); 6 June 1967, D. McMurtry 202 ( PRE). E slopes of Table Mountain , Kirstenbosch , October 1917, M.M. Page n.s. ( BOL). Newlands , May 1907, N.S. Pillans s.n. ( GRA); Slopes of Table Mountain above Newlands , August 1905, N. Pillans BOL10595 ( BOL). Table Mountain National Park , 8 July 2010, R.R. Klopper, A.W. Klopper & E.J. van Jaarsveld 323, 324 & 325 ( NBGgmc, PREgmc). Cape Peninsula, Karbonkelberg , 18 July 1926, H.W.R. Marloth 5133B ( PRE); 5 July 1942, R.H. Compton 13291 ( NBGm); E.S.C. Dyke 5133 ( PRE). Cape of Good Hope Nature Reserve , Boer ridge S of Batsata Nek, 1 August 1983, H.C. Taylor 10551 ( NBG). Cape Point Nature Reserve , between Smitswinkel Bay and Paulsberg , 17 July 1979, E.J. van Jaarsveld 5956 ( NBGm). Fish Hoek Mountains, Cape Peninsula , 15 September 1942, Dr Gonlimis BOL24296 ( BOL). On Steenberg , December 1904, C.B. Fair BOL24295 ( BOL). Steenbras Riv. Mouth , near Palmiet River Mouth , 4 May 1924, H.W.R. Marloth 5132 ( PREm). Groot Hangklip , 11 September 1969, C. Boucher 582 ( NBG, PRE). Hermanus , 1 January 1915, H.W.R. Marloth 97A ( PRE); 8 January 1915, H.W.R. Marloth 97B ( PRE); 6 June 1935, J.C. van Balen 951 ( PREm); Komma beach , 7 July 2010, R.R. Klopper & A.W. Klopper 315 & 316 ( NBGgmc, PREgmc); Kraal rock , 7 July 2010, R.R. Klopper & A.W. Klopper 317 & 318 ( NBGgmc, PREgmc). Caledon Dist. , Klein River Mouth , H.W.R. Marloth 5149 ( NBG, PREm); September 1940, J.P. Stokoe 7821 ( BOL); December 1920, H.W.R. Marloth 10033 ( PRE). Kleinmond , 7 July 2010, R.R. Klopper & A.W. Klopper 319 & 320 ( NBGgmc, PREgmc); At old harbour , 7 July 2010, R.R. Klopper & A.W. Klopper 321 & 322 ( NBGgmc, PREgmc) .

Specimens from other species

Aloe arborescens :— Copenhagen Botanic Garden, Accession no. P2012-5002 (ex hort. g); South Africa, Mpumalanga, Mariepskop, R.R. Klopper & A.W. Klopper 416 (PREg). Aloe arenicola :— South Africa, Northern Cape, Koingnaas, on road to Soebatsfontein, R.R. Klopper & A.W. Klopper 363 (PREg). Aloe broomii :— Copenhagen Botanic Garden, Accession no. P2012-5002 (ex hort. g). Aloe burgersfortensis :— Copenhagen Botanic Garden, Accession no. P2012- 5006 (ex hort. g). Aloe chlorantha :— South Africa, Northern Cape, Farm Tafelberg, E.J. van Jaarsveld 22666 (PREg); South Africa, Northern Cape, Williston, J.P.H. Acocks 16431 (PREm). Aloe claviflora :— South Africa, Northern Cape, Pofadder, Farm Boomrivier, R.R. Klopper & A.W. Klopper 400 (PREg). Aloe comosa :— South Africa, Western Cape, Skitterykloof picnic cite, R.R. Klopper & A.W. Klopper 335 (PREg). Aloe ferox :— Published DNA sequence ( Adams et al. 2000), GenBank accession no. AF 234338 g. Aloe krapohliana :— South Africa, Western Cape, near Vredendal, R.R. Klopper & A.W. Klopper 354 (PREg). Aloe marlothii :— Published DNA sequence (Yessoufou 2012), GenBank accession no. JF 270641 g. Aloe pictifolia :— Copenhagen Botanic Garden, Accession no. S1997-0760 (ex hort. g); South Africa, Eastern Cape, Kouga District, Paul Sauer Dam, G.X. Marais s.n. (PREm). Aloiampelos striatula :— South Africa, Eastern Cape, Tarkastad area, R.R. Klopper & A.W. Klopper 284 (PREg). Aloidendron dichotomum :— South Africa, Northern Cape, Nieuwoudtville, Gannabos quiver tree forest, R.R. Klopper & A.W. Klopper 356 (PREg). Aristaloe aristata :— Published DNA sequence ( Treutlein et al. 2003b), GenBank accession no. AY 323713 g. Kniphofia :— Copenhagen Botanic Garden, DNA bank accession no. C559 (ex hort. g).

Figures

FIGURE 16. Aloe succotrina. A. Known distribution (red shading in white circle). B. Plants froming dense groups. C. Rosette of dull green leaves with few to no white spots. D. Plants with long trailing stems growing over boulders. E. Raceme with glossy red, greentipped flowers and diagnostic broad purple bracts. Photographs:Arrie W. Klopper (B, C. Cape Peninsula, Western Cape, South Africa; D. Kirstenbosch National Botanical Garden, Western Cape, South Africa; E. Kleinmond, Western Cape, South Africa; July 2010).