Aloe hankeyi Gideon F.Sm. & Figueiredo, 2022

Smith, Gideon F. & Figueiredo, Estrela, 2022, Aloe hankeyi (Asphodelaceae subfam. Alooideae; Aloe sect. Leptoaloe), a new species from northern South Africa, Phytotaxa 549 (1), pp. 122-126 : 124-125

Aloe hankeyi Gideon F.Sm. & Figueiredo , sp. nov.

Type: — SOUTH AFRICA. Limpopo province.—2329 (Pietersburg [Polokwane]): about 45 km east of Polokwane , (– DD), in thorn tree bushveld, collected 22 July 1999, cultivated at the Walter Sisulu National Botanical Garden, specimen prepared 3 March 2022, G . F . Smith 1175 (holotype PRU) .

Diagnosis:— Aloe hankeyi has elongated-deltoid leaves that lack a keel, while those of A. cooperi , which also has elongated-deltoid leaves, are distinctly keeled. In contrast, the keel-less leaves of A. verecunda are narrowly linear and much shorter than those of both A. hankeyi and A. cooperi . The flowers of A. hankeyi are consistently dull red at anthesis so differing from the variably salmon-pink to orangey flowers of A. cooperi that are also shorter than those of A. hankeyi . In contrast, the flowers of A. verecunda vary from dull to bright red. The distal ± ⅓– 1 / 5 of the perianths of all three species is variously green-infused, often less so in A. verecunda . Aloe hankeyi further differs from A. verecunda by being considerably more robust in all respects, with plants easily reaching a height of 1 m, as opposed to the 0.20–0.25 m of A. verecunda .

Description:—Large, acaulescent or short-stemmed, erect, clump-forming slender aloe. Stem ± absent or to 15– 20 cm long, usually branched from base to form clumps ; dry leaves not persistent. Leaves 15–20(–22) per rosette, distichous only in young plants, spirally twisted to rosulate in older plants, erect to arch-like curved outwards, (60–) 75–80 cm long, 6–7 cm broad at base, elongated-deltoid, channelled adaxially, not keeled, cymbiform in cross section, dark green, obscurely lineate, with only few scattered spots adaxially, copiously white-spotted at base abaxially, white spots raised; margin with firm but harmless, white teeth, 1–2 mm long, becoming smaller distally, (2–) 4–5 mm apart at mid-leaf; exudate clear. Inflorescence a raceme, 0.6–0.8(–1) m tall, erect, simple; peduncle stout, sparsely sterile bracteate proximally, densely so distally; sterile bracts elongated-triangular, greenish to brownish yellow, rapidly drying light brown, obscurely many-nerved. Raceme broadly conical to ± flat-topped, 11–12 cm long, dense-flowered. Floral bracts 20–35 mm long, 5–8 mm broad at base, clasping pedicels. Pedicels 30–40 mm long. Flowers 40– 45 mm long, 10–12 mm wide across ovary, basally obscurely stipitate, abruptly narrowing into pedicel, copiously nectariferous; perianth ± straight, somewhat narrowing towards mouth, roundly trigonous, dull red for proximal ⅔, greenish in distal ⅓, inner and outer segments distinctly white-margined towards apex; outer segments free almost to base; stamens included, uniformly light yellow; filaments filiform-flattened; ovary (6–)7(–8) mm long, 2–3 mm in diam., light green; style included or exserted for ± 1 mm. Fruit a loculicidal capsule, 21–30 × 9–12 mm, light to midgreen turning light greyish brown with age, dry remains of perianth persistent for a long time. Seed 4–5 × 2–3 mm, light greyish brown to black, ± irregularly D-shaped, angled, with prominent white to transparent wing. Chromosome number: unknown.

Flowering time:—February–March.

Eponymy:— Aloe hankeyi is named for Mr Andrew John Hankey (Johannesburg, Gauteng province, South Africa, 12 February 1968 –) ( Fig. 1H ). Andrew has a longstanding interest in a wide range of succulent plants, including in Aloe , and facilitated access to material of A. hankeyi . He has worked for the South African National Biodiversity Institute for the past 28 years and currently holds a position as Specialist Horticulturalist (see also Smith 2020: 95).

Key to distinguish among Aloe cooperi , A. hankeyi , and A. verecunda :

1. Leaves distinctly keeled abaxially ................................................................................................................................... Aloe cooperi

1’. Leaves lacking a keel..........................................................................................................................................................................2

2. Flowers 40–45 mm long, dull red; sterile bracts densely arranged distally on peduncle................................................... A. hankeyi

2’. Flowers 26–30 mm long, dull to bright red; sterile bracts sparsely arranged distally on peduncle ............................... A. verecunda

Figures

FIGURE 1. A. Aloe verecunda has a wide but patchy natural geographical distribution range in northeastern SouthAfrica.This photograph of a form with bright red flowers was taken in the North West province near the western limits of its range. B. A. cooperi growing in dense grassland near Melmoth in KwaZulu-Natal, South Africa. Note the distinctly conical inflorescences and sparsely arranged sterile bracts higher up on the peduncles. C.A large clump of A. hankeyi in full flower.D. Leaves of A. hankeyi are not keeled, unlike those of A. cooperi, which are distinctly keeled abaxially. E. Racemes of A. hankeyi are broadly conical to distinctly flat-topped. F. The sterile peduncular bracts of A. hankeyi (peduncle on the left) are much more densely concentrated towards the raceme than in A. cooperi (peduncle on the right) or A. verecunda. G. The large flowers of A. hankeyi are dull red for ⅔ of their length, with the upper ⅓ being greenish. H. Andrew John Hankey (1968–) on 21 August 2019. I. Type locality of A. hankeyi (red dot). Unvouchered site records in eastern Gauteng and western Mpumalanga are not reflected on the map. All photographs by Gideon F. Smith.