Aloiampelos tenuior var. ernstii, Gideon F. Sm. & Figueiredo, 2022

Smith, Gideon F., Figueiredo, Estrela, Klopper, Ronell R., Campbell, Eileen E. & Martin, Kristen, 2022, Aloiampelos tenuior var. ernstii, a new orange-flowered variety of rambling aloe (Asphodelaceae subfam. Alooideae), Phytotaxa 571 (1), pp. 91-96 : 94-95

Nomenclature of Aloiampelos tenuior var. ernstii

Aloiampelos tenuior ( Haworth 1825: 281) Klopper & Gideon F.Sm. in Grace et al. (2013: 11) var. ernstii Gideon F.Sm. & Figueiredo , var. nov.

Type: — SOUTH AFRICA. Gauteng province.—2528 (Pretoria): Tshwane , (–CA), ex hort., material originally collected in a domestic garden in Somerset West, Western Cape, South Africa, 20 August 2016, G.F. Smith & E. Figueiredo 42 (holotype PRU) .

Diagnosis:— Aloiampelos tenuior var. ernstii differs from A. tenuior var. tenuior (40–45 mm long yellow flowers) and A. tenuior var. rubriflora (± 20 mm long red flowers) by its shorter (12–15 mm long), orange flowers. Plants of A. tenuior var. ernstii are generally daintier in most vegetative respects, with their leaves generally being narrower than those of A. tenuior var. tenuior and A. tenuior var. rubriflora .

Description.—Perennial, herbaceous, tangled, succulent shrub of 0.75–1.00 m tall. Stems clumped, slender, (0.5–) 0.75–1.00 m long, 5–10 mm diameter, branched low down or higher, erectly spreading or scandent to recurved or decumbent, mostly without persistent dried leaves. Roots cylindrical, 5 mm in diameter. Leaves rosulately and widely cauline-dispersed, erectly spreading to down-curved, papery when dry, dull light green to mid-green, without spots, linear-lanceolate to linear-attenuate, adaxial surface slightly concave to canaliculate; abaxial surface convex, texture smooth, tapering to apex, 7–19 cm long, 0.9–1.1 cm broad at base, basally sheathing; sheath obscurely to distinctly green-lineate, not auriculate, 0.5–2.0 cm long; margin same colour as blade, not cartilaginous, with minute, white teeth, up to 0.5 mm long, 1–5 mm apart. Inflorescence 1–3, borne simultaneously or successively, 10–12 cm tall, rarely once-branched, branch arcuate-erect. Peduncle 60–70 mm long, 3–4 mm broad at base, basally plano-convex, cylindrical above, light green, lacking a white, powdery bloom; sterile bracteate lower down, sterile bracts up to 5, basal bracts deltoid-triangular, apical bracts long-attenuate and hair-like, 3–6 mm long, straw-coloured, scarious, 1–3- nerved. Racemes cylindrical, 5–8 cm long, 4–5 cm wide; buds erect to suberect, flowers horizontal to drooping when mature. Floral bracts tapering long-attenuate and hair-like from a deltoid triangular base, not amplexicaul around pedicel, 3–4 mm long, 1.0– 1.5 mm wide, straw-coloured, papery, 3- or 4-nerved, central nerve dark brown, prominent. Pedicels 3–4 mm long, light green. Flowers: actinomorphic, unscented, nectariferous; perianth orange, yellow towards tip, tip extremity green in bud and when mature, not pruinose, 12–15 mm long, rounded at base, ± 3 mm across ovary, enlarging to 4 mm towards wide open mouth, cylindrical, tubular-cymbiform; outer segments lorate, free for ± 4 mm, free portion centrally green, borders yellow, acute, blunt-tipped, segment margins straight, tips slightly flared open; inner segments ± same size as outer segments, with yellow border and slightly more obtuse apex, free for ± 4 mm; s tamens with cylindrically thread-like, light yellow, basally inserted filaments, 12–15 mm long, all 6 of ± equal length, prominently exserted for 2–3 mm; anthers small, 1–2 mm long, yellow, fading brown, versatile; ovary 3–4 mm long, ± 2 mm in diameter, light yellow; style as long as or slightly longer than stamens, minutely capitate, with small stigma, exserted 1–2 mm. Fruit not seen. Seeds not seen. Chromosome number unknown.

Phenology:—The varieties recognised in A. tenuior flower at various times of the year, and have also been known to sporadically produce inflorescences out of season. Like A. tenuior var. densiflora , A. tenuior var. ernstii flowers during winter, but will also produce inflorescences well into spring. However, A. tenuior var. densiflora has yellow, not orange, flowers.

Vernacular names:—The large number of vernacular names—12 that we are aware of—recorded for A. tenuior attests to its popularity in horticulture and its uses in traditional medicine ( Grace et al. 2011: 152). The names include: rankaalwyn and heuningaalwyn (Afrikaans); fence aloe (English); ikhalane (Xhosa); and inhlaba empofu (Zulu).

Eponymy:— Aloiampelos tenuior var. ernstii is named for Dr Ernst Jacobus van Jaarsveld (19 February 1953, Johannesburg , Gauteng province, South Africa –). Ernst matriculated from Linden High School after which he studied for and was awarded a National Diploma in Horticulture in 1975. In 1990 he graduated with an M.Sc. in plant systematics from the University of Natal , now the University of KwaZulu-Natal. In 2012 Ernst was awarded a Ph.D. by the University of Pretoria for his work on cremnophytic plants. Dr Van Jaarsveld was employed by the South African National Biodiversity Institute for more than 40 years, where after he accepted an appointment at Babylonstoren Farm , near Simondium , Western Cape province, where he is inter alia involved in establishing a succulent plant collection. In these positions he has mentored and trained several young horticulturists. Ernst has a longstanding interest in succulents and has contributed significantly to our knowledge of the southern African flora in general.

Cultivation:—Although A. tenuior var. ernstii was commonly grown in gardens in many parts of South Africa some 40 to 50 years ago, it is now much less often cultivated. This can likely be attributed to this variety in some respects being less vigorous in cultivation, when compared to A. tenuior var. tenuior and A. tenuior var. rubriflora . However, this new variety is easy in cultivation. The lower portion of stem cuttings of 20–50 cm long can be placed in the soil directly in the place where they are intended to grow. Plants grow well in full sun as well as in dappled shade.