Aloe microstigma subsp. juttae (Dinter) Klopper, 2023

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

4b. Aloe microstigma subsp. juttae (Dinter) Klopper comb. et stat. nov. ( Fig. 15 )

Basionym: — Aloe juttae Dinter (1923: 159) . Type :— NAMIBIA: Gubub, 7 June 1922, M.K. Dinter 3601 (lectotype [designated here] B B 10 1244036!, as ‘holotype’ [http://herbarium.bgbm.org/object/ B101244036 ]; isolectotypes B B 10 1244034! & B 10 1244035! [2 sheets] as ‘holotype’ [http://herbarium.bgbm.org/object/ B101244034 ; http://herbarium.bgbm.org/object/ B101244035 ], BOL BOL140198 ! as ‘isotype’ [https://plants.jstor.org/stable/viewer/10.5555/al.ap.specimen.bol140198], DR DR081354 ! [https://dr.jacq. org/ DR081354 ], PRE! PRE0090536-1 & -2 [2 sheets] as ‘isotype’ [https://plants.jstor.org/stable/viewer/10.5555/al.ap.specimen. pre0090536-1; https://plants.jstor.org/stable/viewer/10.5555/al.ap.specimen.pre0090536-2], SAM SAM0073732 -0! as ‘isotype’ [https://plants.jstor.org/stable/viewer/10.5555/al.ap.specimen.sam0073732-0]).

Note regarding type:— The protologue of A. juttae ( Dinter 1923) states that the holotype of this name is in Herb. B and that isotypes are at Herbs. BOL, PRE, and SAM. During this study, a further, previously uncited, duplicate was traced at Herb. DR.

Two duplicates of Dinter 3601 could be traced at Herb. B. One duplicate consists of two sheets (B 10 1244034 & B 10 1244035) and shows signs of insect damage; sheet I contains two inflorescences and an envelope with the remains of flowering and fruiting material, while sheet II consists of two leaves. The second duplicate (B 10 1244036) consists of a leaf, an inflorescence, and an envelope with a flower and what appears to be a bract. The duplicate with barcode B 10 1244036 is here designated as lectotype as it shows all the diagnostic characters of the species and is in a better state of preservation than the other duplicate at Herb. B that consists of two sheets (B 10 1244034 & B 10 1244035).

Description:— Acaulescent to shortly caulescent plants; rosettes in dense groups. Leaves densely rosulate, erectly spreading, blue-green, often reddish, with few elongated white spots on both surfaces, narrowly lanceolate, gradually attenuate, ± 30 cm long, 2.5–4.5 cm wide; margin with pungent, deltoid, reddish brown teeth, 0.5–2.0(–3.0) mm long, 4–8 mm apart; leaf exudate yellow, drying yellow. Inflorescence single or up to 3 per rosette simultaneously, ± 0.6 m high, erect, simple or often 2- or 3-branched from below middle. Peduncle 1.1–1.4 cm wide and plano-convex below, terete upwards, reddish green to brown; with sterile bracts, acute, 20–25(–32) mm long, 10–14(–18) mm wide, pale, scarious, 8-nerved. Racemes cylindrical, (25–) 30–40 cm long, erect, dense; buds erect to spreading, flowers nodding when open. Floral bracts broadly lanceolate, acute, amplexicaul, 12–20 mm long, 4–6 mm wide, reddish brown, rather scarious, 5- to 7-nerved. Pedicels 15–20 mm long, red. Flowers: perianth bright orange-yellow to orange-red, green-tipped, (18–)20–28(–30) mm long, 7 mm across ovary, not narrowed above ovary, cylindrical; outer segments free to base, tips slightly spreading; stamens with filiform flattened filaments, yellow with exserted portion turning purplish brown, shortly exserted or included; ovary 5 mm long, 2.0– 2.5 mm diameter, green; style bright yellow, exserted 4–5 mm.

Diagnostic characters:— Aloe microstigma subsp. juttae is distinguished by its dense rosette clusters forming a disorderly shrub. Leaves are usually copiously white-spotted and narrow (2.5–4.5 mm wide), with reddish brown marginal teeth of 0.5–2.0 mm long. Inflorescences are simple or often 2- or 3-branched, ± 0.6 m high, and usually with unicoloured to only very slightly bicoloured racemes of 30–40 cm long. Floral buds are orange-red and mature flowers orange-yellow to orange-red and 20–28 mm long. Pedicels are 15–20 mm long. Floral bracts (12–20 mm) are about as long as the pedicels. Leaf exudate does usually not dry purple (dries yellow).

Distribution:— Only known from southwestern Namibia, isolated mountains in Bushmanland, and the Richtersveld, Northern Cape, South Africa. Endemic to the Gariep Centre of Endemism.

Habitat:— Granite ridges with large scattered boulders.

Elevation:— 1 000–1 600 m

Flowering time:— May–June

Etymology:— Commemorates Mrs Jutta Dinter (fl. 1906–1935), wife of Namibian botanist M.K. Dinter (author of the basionym).

General notes:— This taxon was originally described as Aloe juttae , but has long been treated as a synonym of Aloe microstigma ( Reynolds 1950) .

Additional specimens examined:— SOUTH AFRICA. Northern Cape: Pofadder, farm Boomrivier, on Slangberg , 21 July 2010, R.R. Klopper & A.W. Klopper 396 ( KMG, PRE). NAMIBIA. Luderitz, Klein Aus Farm LU8, 24 June 1974, J.W.H. Giess 13368 ( PREm). Between Gubub and Aus , 7 June 1922, M.K. Dinter 3601 (isotypes BOL, PREm, SAM). Farm Kubub LU 15, 9 September 1973, J.W.H. Giess 12864 ( WIND); no date, J.W.H. Giess & D. van Vuuren 793 ( WIND); Farm Kubub , just S of Aus , 18 July 2010, R.R. Klopper & A.W. Klopper 387 & 388 ( NBGgc, PREgc, WINDgc). Klinghardtberge , 20 September 1977, H. Merxmüller & J.W.H. Giess 32202 ( WIND). Heiob Mountains , 15 February 1984, M.B. Bayer 3885 ( NBG). Witputz, Aurus Mountains , Rooiberg , D.S. Hardy 5056 (PREm). Luderitz, Witputz-Sud LU31 Farm , 26 June 1975, M.A.N. Müller & W.J. Jankowitz 294 ( PREm, WIND); 16 June 1976, J.W.H. Giess & M.A.N. Müller 14424 ( PREm, WIND); S of Witputs , fl. hort. Stellenbosch University , H. Herre SUGardens 7119 ( BOL). Rosh Pinah , Numeis , 2 September 2000, P.V. Bruyns 8835 ( NBG); S of Farm Zebrafontein 87, 28 August 2003, P.V. Bruyns 9479a ( WIND). Namibia, ex Triebner, fl. in hort. Frames, Kenilworth , July 1935, P. Ross Frames s.n. ( BOL) .

Figures

FIGURE 15. Aloe microstigma subsp. juttae. A. Known distribution (red shading). B. Dense, multi-headed cluster of rosettes. C. Rosette of thin, blue-green leaves with white spots during a period of above-average rainfall. D. Rosettes of reddish leaves during a dry season. E. Raceme with orange-red flowers. Photographs: B, D. Arrie W. Klopper (Aus, Namibia, July 2010); C, E. Japie C. Kruger (Pofadder, Northern Cape, South Africa, June 2006).