Aloe labiaflava Groenewald (1936: 58)

Smith, Gideon F. & Klopper, Ronell R., 2021, 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), pp. 179-189 : 181-188

Aloe labiaflava Groenewald (1936: 58)

Also treated in: Groenewald (1941: 87, 104, 134, 139 [page not numbered], Map no. 11).

Type: — SOUTH AFRICA, Transvaal [Mpumalanga province], Gemsbokspruit , August 1935, F. Z. van der Merwe 100 (lectotype, PRE; https://plants.jstor.org/fsi/img/size2/alukaplant/pre/phase_01/pre0005/pre0084275-0.jpg), designated as “ Neotype ” by Glen et al. (1995: 98); here corrected to lectotype .

Epitype:— SOUTH AFRICA, Mpumalanga province, Gemsbokspruit , rocky ridge in grassland, 23 August 2020, G. F. Smith 1120 ( PRU!), here designated .

Notes on the lecto- and epitype:— Glen et al. (1995: 98) designated the specimen F. Z. van der Merwe 100 (Herb. PRE) from [ South Africa], Transvaal [Mpumalanga], Gemsbokspruit, as “ Neotype ”. Where the name A. labiaflava was published ( Groenewald 1936: 58), no specimens were cited, as noted by Glen et al. (1995: 98). However, an illustration (a black-and-white line drawing) accredited to “ F. V.D. M.”, a very likely reference to Dr F. Z. van der Merwe (10 December 1894 – 2 January 1968), a medical inspector of schools and amateur botanist ( Verdoorn 1966: 59–60, Gunn & Codd 1981: 355, Glen et al. 1995: 97–98), with the handwritten heading “ ALOE LABIAFLAVA ” was published on an unnumbered page opposite p. 58 in Groenewald (1936). Van der Merwe is known to have provided his novel aloe collections to Groenewald for description during the 1930s ( Klopper et al. 2013).

The illustration published in Groenewald (1936: unnumbered page opposite p. 58) constitutes original material under Turland et al. (2018: Art. 9.4(b)). A coloured plate (dated “ 1.9.1935 ”), of which the corresponding components (habit illustration, separate bud and flower, leaf, and frontal view of flower mouth) are identical to those in the illustration in Groenewald (1936), is held at Herb. PRE ( Fig. 7 ). This illustration bears a reference to “no. 100, TIPE!, FvdM”. The Herb. PRE specimen F. Z. van der Merwe 100 also constitutes original material, under Turland et al. (2018: Art. 9.4(a)), as it was collected in August 1935. While the exact date of publication of volume 14 of the Tydskrif vir Wetenskap en Kuns is not certain, the copy of this volume of the journal held in the Mary Gunn Library of the South African National Biodiversity Institute carries an official stamp that indicates that it was received on 14 February 1936, with the publication date therefore likely having been sometime in the first six weeks of 1936, which post-dates the collecting date of F. Z. van der Merwe 100 by five to six months. The F. Z. van der Merwe specimen was therefore available to Groenewald. Furthermore, even although not cited by Groenewald (1936), the original label on the specimen contains the word “Tipe” (Afrikaans for ‘Type’) in what is believed to be the handwriting of F. Z. van der Merwe.

We here correct use of “ neotype ” by Glen et al. (1995: 98) to “ lectotype ” under Turland et al. (2018: Art. 9.10).

Material preserved as the type, F. Z. van der Merwe 100, is devoid of a rosette, consisting of a small piece of a leaf and two inflorescences only. An epitype, G. F. Smith 1120 (deposited at Herb. PRU), with an intact rosette and inflorescence is here designated as an interpretative type, collected from the same locality as the lectotype of the name A. labiaflava .

Description:—Plants small, low-growing, solitary, rarely once-branched from the base, rosette erect, up to (10–) 20 cm tall. Stem ± absent, short, simple and thickened lower down if present, clothed in persistent, twisted, dried leaves. Leaves very densely rosulate, at first erect, then horizontally spreading, 5–15 cm long, 7–10 cm wide at base, dull greenish to purplish blue to glaucous, deltoid-lanceolate, abaxially pale green, faintly white-spotted, longitudinally purple-lined, lines narrow, somewhat confluent, adaxially more densely white-spotted, purple-lined but less so than abaxially, white spots ± oblong, sometimes arranged in interrupted, wavy transverse bands, texture smooth; margins shiny-orange-brown to shiny-dark brown, armed with prominent, short, very pungent, deltoid, shiny-brown, yellowish tipped teeth, ± 4–6(–9) mm long, 3–5(–9) mm apart, variously curved towards leaf base or more rarely straight. Inflorescence usually only one produced per season, unbranched raceme or 2- to 4-branched panicle, 0.6–0.8 m tall, erect, branched at or below middle, branches erect at narrow angle from peduncle; peduncle rather stout, lacking sterile bracts below racemes, panicle branches subtended by prominent fertile bracts of ± 25–40 mm long, drying rapidly, dull light brown to creamy white, irregularly deltoid to lanceolate-triangular, distinctly longitudinally dark brown lined. Racemes narrowly cylindrical, somewhat tapering upwards, 10–30 cm long, ± 4–6 cm wide where flowers are at anthesis, usually rather densely flowered; buds erect to erectly spreading, flowers pendulous at anthesis. Floral bracts ± 15–20 mm long, prominent, as long as or longer than pedicels, drying rapidly, light brown to creamy white, narrowly lanceolate, variously twisted, much narrower than fertile bracts. Pedicels (5–)10–15(–20) mm long, orange to reddish orange when young, light green with age. Flowers: perianth: buds uniformly orange to reddish orange, green-tipped; open flowers bright orange to bright reddish orange for basal ⅔, whitish yellow to golden yellow in apical ⅓, ± 30 mm long, ± 6–7 mm across ovary, narrowed above ovary to yield small bulbous base, distinctly enlarged towards mouth, middle ± cylindric, ± straight to down-curved to horizontally spreading; tips of segments distinctly flared, outer segments free for ½ of their length; stamens with filiform-flattened filaments, uniformly light yellowish white, exserted for up to 3–6 mm; ovary 6–7 mm long, 2–3 mm in diam., light green; style well-exserted, uniformly light yellow; stigma tiny, very slightly capitate, yellowish. Fruit a capsule, 15–20 × 8–10 mm, dull mid-green to purplish green, dry remains of perigone persistent for long time. Seed not seen. Chromosome number: unknown.

Distribution:— Aloe labiaflava has a small natural geographical distribution range around KwaMhlanga and Gemsbokspruit in western Mpumalanga province, South Africa ( Fig. 8 ).

Additional specimens investigated:— SOUTH AFRICA, Mpumalanga, Gemsbokspruit , December 1935, F. Z . van der Merwe 101 ( PRE!); August 1936, F. Z . van der Merwe s.n. ( PRE 21377) ( PRE!, [2 sheets]); 31 July 1938, G. W . Reynolds 2881 ( PRE!); 23 August 2020, G. F . Smith 1120 ([the epitype held at] PRU!), 23 August 2020, G. F . Smith 1121 ( PRU!) .

When Reynolds (1950: 293) concluded that A. labiaflava was a cross between A. davyana and A. longibracteata he inexplicably did not reference any of the Herb. PRE specimens we cite here, even although he himself collected a specimen of A. labiaflava , which he identified as A. longibracteata , at the type locality of A. labiaflava .

Figures

FIGURE 7. Coloured plate, dated “1.9.1935” and held at Herb. PRE, of which the corresponding components (habit, bud and flower, leaf, and frontal view of flower mouth) are identical to those in the illustration in Groenewald (1936: unnumbered page opposite p. 58).

FIGURE 8. Known distribution of Aloe davyana var. davyana (green), Aloe labiaflava (red), and Aloe longibracteata (orange).