Thesium confine Sond.

Mashego, Kagiso S. & Roux, M. Marianne le, 2018, A taxonomic evaluation of the Thesium confine species complex (Santalaceae), Bothalia - African Biodiversity & Conservation 48 (1), pp. 1-6 : 3-4

1. Thesium confine Sond.

in Flora 40: 363 (1857); DC., Prodr. 14: 665 (1857); A.W.Hill in Fl. Cap. 5(2): 176 (1925).

Type: SOUTH AFRICA, Free State: ‘ Trans-Garipina, Nieuwejaarspruit , zwischen Garip und Calendonrivier , am Fuss der Witbergen’ [ Nieuwejaarspruit , between Gariep River and Calendon River, at the foot of Witberg], October, Zeyher 114 ( S, holo. – digital image! ; K, S – digital image!, iso.) .

Thesium spartioides A.W.Hill , in Bull. Misc. Inform. Kew 1915 (1): 41 (1915); Hill in Fl. Cap. 5(2): 176 (1925), syn. nov.

Type: SOUTH AFRICA, Mpumalanga: ‘in collibus pr. Brug Spruit’ (on the hills near Brug Spruit), 19 November 1893, Schlechter 3754 ( K, holo. – digital image!; BOL – digital image!, HBG – digital image!, NBG – digital image! ; PRE [four sheets]!, S [two sheets] – digital image!, iso.) .

Description: Slender perennial with slightly woody rootstock and decumbent habit, branching from rootstock, 70 mm – 280 mm high; stems wiry, 1 mm – 3 mm diam. Leaves scalelike, closely adpressed to stem, imbricate on young twigs, lanceolate, acuminate, 1.2 mm – 3.3 mm × 0.2 mm – 0.6 mm, margins ciliate. Inflorescences terminal (rarely axillary), monotelic, of 5- to 8(9)-flowered spike-like cymes (with single flowers sometimes replaced by 3-flowered monochasia), peduncles 5 mm – 38 mm long; involucral bracts usually absent; bracts ovate, acuminate, 1.4 mm – 1.5 mm × 1.0 mm – 1.1 mm, adpressed to flower; bracteoles 2, lanceolate, acute, 1.4 mm – 1.7 mm × 1.0 mm – 1.2 mm. Flowers white, tubular, subsessile, perianth tube 2.0 mm – 2.4 mm long, lobes ± 1 mm long, densely bearded with white hairs. Stamens inserted at base of the perianth tube; filaments 0.1 mm – 0.2 mm long, obscured by anthers; anthers 0.4 mm – 0.5 mm long. Style and stigma 0.5 mm – 0.7 mm long, stigma opposite middle or top of anthers. Placental column twisted. Fruit subglobose, brown, with 10 longitudinal ribbed veins, reticulate between main veins, 2 mm – 3 mm diam., shortly stiptitae, stipe 0.5 mm – 0.7 mm long. Flowering time: August to Octoberand December to January.

Distribution and ecology: Thesium confine is endemic to northern and interior South Africa, extending from near Wolmaransstad in North West province and Spitskop in the Steelpoort area of Mpumalanga province southwards through Gauteng and Free State to Middelburg in Eastern Cape province ( Figure 2 ). It grows in grassland in sand, clay or loam.

Diagnostic characters and relationships: Thesium confine differs from T. durum in its herbaceous versus woody habit, slender, decumbent stems up to 3 mm diam. versus thicker, erect stems (3 mm – 6 mm diam.), inflorescences terminal and sometimes axillary versus axillary only, and in usually lacking involucral bracts versus invariably with involucral bracts.

Conservation status: Thesium confine is listed as Least Concern because it is widespread and abundant ( Foden & Potter 2005b).

Additional specimens seen: SOUTH AFRICA. MPUMALANGA. – 2430 (Pilgrim’s Rest): ± 2 km from Spitskop turn-off off Steelpoort and Lydenburg road, (– CB), 2 Apr. 1997, M. Jordaan 3143 ( PRE). 2529 (Witbank): Doornkop 273 JS, vlei wes van Eerstekamp [marsh west of Eerstekamp], (– CB), 29 Oct. 1968, C.J. du Plessis 883 ( PRE, PRU) ; El Shaddai, Zeekoeiwater plot 152, Emalahleni, next to the Olifants River, (– CD), 9 Oct. 2016, N. Visser & M. leRoux 195 ( PRE) ; next to the road on the R 104, 18 km east of Middelburg, (– DC), 26 Oct. 2016, N. Visser & M. leRoux 208 ( PRE). 2730 (Vryheid): north of Dirkiesdorp, south-east of main road, (– AB), 13 Dec. 1995, K. Balkwill 9398 ( PRE) .

GAUTENG. – 2528 (Pretoria): Pretoria, (– CA), 15 Oct. 1963, H. U. Scheepans & J. C Stauffer 5300 ( K) ; Pretoria, norden- Eingang Irene, zwischen Bahn und Wellington-Strasse [northern entrance in Irene, between Bahn and Wellington streets], (– CC), 15 Oct. 1963, H. U. Stauffer 5300 ( PRE). 2627 (Potchefstroom): Leeuwkuil Research Station, (– DB), 17 Oct. 1939, J. P. H. Acocks 16200 ( PRE) ; Vereeniging, (– DB), 1 Nov. 1911, R. Leendertz 3940 ( PRE). 2628 (Johannesburg): Modderfontein, (– CB), 1 Dec. 1943, A. P.D. McClean 52808 ( PRE) .

NORTH WEST. – 2725 (Bloemhof): Leeuwfontein, 10 km wes van Wolmaransstad plaas van J. J. van Wyk op kalkbanken [10 km west of Wolmaransstad, farm of J. J. van Wyk on kalk bank], (– BB), 25 Mar. 1978, A. E. van Wyk 2240 ( PRE, PRU) ; Makwassie, op pad na Wolmaransstad by Leeuwfontein uitdraaipad [Makwassie, on the road to Wolmaransstad at Leeuwfontein turn-off], (– BD), 28 Sep. 1974, A. E. van Wyk 570 ( PRE) .

FREE STATE. – 2725 (Bloemhof): 5 mi [8.1 km] north-east of Hoopstad, (– DD), 21 Feb. 1946, J. P. H. Acocks 12486 ( PRE). 2826 (Boshoff): Boshoff, Modder River, Paardeberg, (– CA), 20 Dec. 1937, J. P. H. Acocks 8544 ( PRE) ; Inhoek Krugerdriftdam Nature Reserve, (– CC), 6 Nov. 1974, D. B. Muller 1485 ( PRE) ; Glen Agricultural College, (– CD), 21 Jan. 1900, J. A. van der Berg 3950 ( PRE). 2926 (Bloemfontein): Bloemfontein, (– AA), Dec., unknown collector 1906 ( K) ; Townlands, (– AA), 18 Mar. 1975, E. R. Anderson 26 ( PRE). 3025 (Colesburg): Bethulie, Tussen die Riviere Wildtuin, (– AD), 14 Nov. 1970, B. R. Roberts 5520 ( PRE) .

EASTERN CAPE. – 3124 (Hanover): 3 mi [4.8 km] north-west of Middleburg, (– BD), 10 Mar. 1955, J. P. H. Acocks 17970 ( PRE). 3125 (Steynsburg): Middleburg ; Grootfontein above camp 6, (– AC), 10 Mar. 1955, J. P. H. Acocks 17971 ( PRE) .

Figures

FIGURE 2: Distribution map Thesium confine (circles) and Thesium durum (triangles).