Stenoglottis macloughlinii (L.Bolus)

Phillips, Dean P. & Bytebier, Benny, 2020, A taxonomic revision of Stenoglottis (Orchideae, Orchidoideae, Orchidaceae), Phytotaxa 456 (3), pp. 219-243 : 239-241

6. Stenoglottis macloughlinii (L.Bolus) G. McDonald ex Shaw (2003: 79). ( Figs 11–12 )

Basionym: Cynorkis [ Cynorchis ] macloughlinii Bolus (1928: 139) .

Type:— SOUTH AFRICA. Eastern Cape: East Griqualand, Lusikisiki , date unknown (ex hort. Nov 1923), Fraser NBG 164/23 (lectotype, designated by Linder & Kurzweil, 1999: BOL, 150445!) .

Heterotypic synonym:— Stenoglottis woodii f. galantha Shaw (2007: 24) . Type:— SOUTH AFRICA. KwaZulu-Natal: about 1.5 miles from Port Edward on Izingolweni Road , the farm Beacon Hill , 21 Oct 1976, Stewart 1810 (holotype: WSY, 0100906, photo!) .

Lithophytic or terrestrial. Leaves 5–15, broadly lanceolate to oblanceolate, unspotted, concolourous green or purple below, margins flat, entire, up to 12.5 × 2.2 cm. Inflorescence up to 35 cm tall with 10–40 flowers; sheaths unspotted. Bracts lanceolate, acute to acuminate, unspotted, sheathing, always shorter than ovaries, 5.0–8.0 × 2.0– 3.3 mm. Flowers white or pink, often spotted with a darker shade of pink or purple on the labellum only; not self-pollinating. Sepals ovate to narrowly ovate or elliptic, acute to obtuse, dorsal concave, laterals oblique, 3.3–5.3 × 1.6–2.9 mm, laterals slightly longer. Petals ovate, oblique, acute, 2.7–4.4 × 1.7–2.6 mm. Labellum spurred, broadly obovate to cuneate in outline, 5.9–9.5 × 5.2–8.3 mm; side lobes broad, truncate or rounded, margins entire; midlobe rounded or obtuse, subequal or slightly shorter than side lobes; spur tapering, straight or recurved, 2–3 mm × 0.3–0.4 mm at the apex, nectar-producing. Column up to 2.0 mm long; stigmatic arms parallel to labellum in mature flowers, curving outward; auricles large, clavate, up to 0.65 mm × 0.45 mm at the apex, projecting beyond the anther between the pollinia and stigmas. Ovary 7.5–12.5 mm long.

Diagnostic characters:— The most notable feature of S. macloughlinii is its spur, which is relatively long (2.0– 3.0 mm) and markedly tapered (i.e. having a broad spur entrance and narrowing gradually toward the apex; Fig. 12B–C ). Of the described Stenoglottis taxa, it appears to be the only one that is nectar-producing (see notes under putative hybrids for an exception). It is also the first species to begin producing new leaves after winter dormancy and the earliest to flower, starting in late October to early November and peaking in December. Stenoglottis macloughlinii is only likely to be mistaken for S. woodii (see that species for a detailed diagnosis).

Notes:— This species was originally described in Cynorkis and was synonymised with S. woodii by Stewart (1989), although she did not make a combination in Stenoglottis . Its reinstatement as a distinct species ( McDonald 1995, Shaw 2003) is well supported by morphological evidence; multivariate morphometric analyses resolved S. woodii and S. macloughlinii as discrete morphological clusters, and their distinction is further supported by differences in their plastid DNA ( Phillips & Bytebier 2020).

Distribution and ecology:— Stenoglottis macloughlinii occurs in the Eastern Cape and KwaZulu-Natal, South Africa, mostly within the Pondoland centre of endemism ( Fig. 11 ), at elevations of 10– 700 m. A single specimen (Morze s.n.) has also been recorded in the Western Cape from the Saasveld between George and Knysna. It occurs most commonly as a lithophyte, occasionally as a terrestrial in shallow soil, and has similar habitat preferences to that of S. woodii , forests or forest margins usually in partial shade along the tops of south-facing cliffs, occasionally in full sun on rocky outcrops in grassland. It has also been recorded in deep shade on boulders in forests, where it occasionally co-occurs with S. fimbriata var. fimbriata . It flowers late October–February and is not self-pollinating.

Specimens examined:— SOUTH AFRICA. KwaZulu-Natal: 3030 (Port Shepstone): Umzinto, Friedenau farm, 457 m (– AD) , 18 Dec 1966, Hilliard 4077 ( E, NH, NU0010113 !) ; Dumisa, Jolivet, B of Ellesmere 6949, ca. 1.5 km SE of Fairfield homestead, 620 m (– AD) , 9 Dec 1992, Ngwenya 1076 ( NH0120475 -0!); Dumisa, Fairfield farm, 700 m (– AD) , 26 Dec 1908, Rudatis 569 ( BM001172121 !, K001208117 !) ; Dumisa, Moyeni , 700 m (– AD) , 21 Dec 1910, Rudatis 1272 ( WAG1140775 photo!); Mgayi [Umgai], forested gorge running into the Mtwalume , 420 m (– AD) , 9 Dec 1992, Scott-Shaw 5046 ( CPF0021095 !) ; Mgayi [Umgai] (– AD) , 22 Feb 1965, Strey 6211 ( K001208118 !) ; Ixopo, Mtwalume Mission Reserve, NW boundary on Highflats road (– BC) , 22 Dec 1965, Burtt & Hilliard 3398 ( BOL 96152!, E, NU0036102 !) ; Dumisa, Ifafa , 500 m (– BC) , 26 Mar 1908, Rudatis 336b ( NH0106443 -0!); Mgayi , on ledges of south facing cliff, 396 m (– BC) , 27 Jan 1968, Ward 6341 ( NH0064244 -0!, NU0010112 !); Oribi Gorge Nature Reserve, Hell’s Gates , under power lines, 630m (– CA) , 19 Jan 1994, Scott-Shaw & Meter 5940 ( CPF0021101 !) ; Oribi Gorge Nature Reserve, Hell’s Gates , under power lines, 630 m (– CA) , 19 Jan 1994, Scott-Shaw & Meter 5949 ( CPF0021102 !) ; Oribi Gorge (– CB) , 3 Jan 1948, Dodds 94 ( NU0010102 !) ; Izotsha Falls , view site (– CB) , 6 Jan 1965, Hilliard 3027 ( E, NU0036101 !) ; Oribi Gorge (– CB) , date unknown (ex hort. 23 Dec 1964), Hilliard s.n. ( BOL 49905!) ; Oribi Gorge Nature Reserve , 452 m (– CB) , 6 Dec 2016 (ex hort. Jan 2018), Phillips & Kiepiel 41 ( BNRH!, NU0088379 !) ; Paddock, Excelsior farm (– CB) , 8 Dec 1970, Strey 10333 ( NH0068482 -0!); Alfred, escarpment above Otterburn , 609 m (– CC) , 2 Jan 1965, Burtt 2999 ( PRU!) ; Umtamvuna Nature Reserve, Klipspringer , 382 m (– CC) 7 Jan 2016 (ex hort. Jan 2018), Grieve et al. 1978 ( BNRH!, NU0088291 !) ; Umtamvuna Nature Reserve, Cubica Heights , 386 m (– CC) , 7 Jan 2016, Grieve et al. 1979 ( NU0088292 !) ; Umtamvuna Nature Reserve, Cubica Heights , 386 m (– CC) , 7 Jan 2016, Grieve et al. 1980 ( NU0088293 !) . Eastern Cape: 3129 (Port St Johns): Lusikisiki, Isicezula Forest , bordering Mazizi Tea Estate (– BC) , 8 Dec 1986, Van Wyk & Mathews 7861 ( PRU!) ; Lusikisiki, Lupatana , cliff faces above river, 15 m (– BD) , 30 Dec 1991, Cloete 1663 ( NH0114392 -0!); Lusikisiki, Lambasi area, Tezana [Thezane] (– BD) , 29 Nov 2002, Nombekela 365 ( NH0141897 -0!); Mkambati Nature Reserve, sandstone outcrops above Msikaba River behind the Reserve Office and Lodge , 104 m (– BD) , 22 Nov 2000, Peter 316 ( NU0010118 !) ; Msikaba, road to Msikaba Drifter’s Camp , 158 m (– BD) , 13 Dec 2016 (ex hort. Jan 2018), Phillips & Kiepiel 42 ( BNRH!, NU0088380 !, NU0088381 !) ; Mateku Falls , 435 m (– BD) , 14 Dec 2016, Phillips & Kiepiel 43 ( NU0088382 !) ; Lusikisiki, Lupatana , 115 m (– BD) , 15 Dec 2016, Phillips & Kiepiel 44 ( NU!) ; Msikaba, on bank of Msikaba River near mouth, 24 m (– BD) , 16 Dec 2016, Phillips & Kiepiel 45 ( NU!) ; Msikaba, on bank of Msikaba River near mouth, 21 m (– BD) , 16 Dec 2016, Phillips & Kiepiel 47 ( NU0088384 !) ; Mateku, Tezana River, adjacent to Lambasi Lodge (– BD) , 29 Nov 2002, Poorun 108 ( NH0132458 -0!); Mateku Falls , 460 m (– BD) , 27 Nov 2002, Singh 810 ( NH0141866 -0!); Mateku Falls (– BD) , 4 Dec 1969, Strey 8499a ( BOL 49919!) ; Lusikisiki, Mkweni River , 1.5 km upstream from mouth (– BD) , 9 Dec 1986, Van Wyk & Mathews 7876 ( PRU!) ; Lupatana [Impatana, Transkei], 25 Oct 1997, Weeks 429 ( GRA0005160 !) ; Mboyti, Fraser Falls , 442 m (– DA) , 18 Dec 1962, Hilliard 1086 ( NU0010116 !) . 3130 (Port Edward): Umtamvuna Nature Reserve, Razor Back (– AA) , 29 Dec 1984, Abbott 2325 ( NH0082427 -0!, PRU!); Umtamvuna Nature Reserve, Beacon Hill , 352 m (– AA) , 24 Dec 2015, Grieve 1911 ( NU0088289 !) ; Port Edward, Izingolweni Road , 91 m (– AA) , Jan 1951, Huntley 746 ( NU0036103 !) ; Umtamvuna Nature Reserve (– AA) , 2 Dec 1982, Schrire 1373 ( NH0076049 -0!); Mnyameni coast [Umyameni] (– AA) , Jan 1941, Thompson s.n. ( NU0010108 !) ; Port Edward, Sea View , 335 m (– AA) , Dec 1949, Ward 1118 ( NU0036104 !) . Western Cape: 3322 (Oudtshoorn): Saasveld , on old road between George and Knysna (– DC) , 16 Nov 1971, Morze s.n. ( NBG0093740 -0!) .

Figures

FIGURE 11. Distribution of Stenoglottis woodii (white) and S. macloughlinii (black).

FIGURE 12. Selected specimens of Stenoglottis macloughlinii. A–C, inflorescence, flower lateral view (showing spurred labellum and sheathing bract) and spur close-up, Umtamvuna Nature Reserve (KZN). D, flowers, Msikaba (EC). E, habit (in situ), Elim Mission, Paddock (KZN). F, habitat, Lake Eland Game Reserve (KZN). G–H, column lateral and ventral view, Msikaba (EC). Scale bars = 5 mm (A–B, D), 2 mm (C), 0.5 mm (G–H). Abbreviations: au = auricle, an = anther, stg = stigmatic arm. E–F reproduced with the permission of Herbert Stärker.