Euphorbia schinzii subsp. schinzii

Bruyns, Peter V., Klak, Cornelia & Hanáček, Pavel, 2020, A review of the Euphorbia schinzii-complex (Euphorbiaceae) in southern Africa, Phytotaxa 436 (3), pp. 201-221 : 213

8a. Euphorbia schinzii subsp. schinzii

Euphorbia complexa Dyer (1937 : t. 643). Type:— SOUTH AFRICA. Transvaal (Mpumalanga): Road from Louw’s Creek to Kaapmuiden, June 1936, Van der Merwe 100 sub PRE 21373 (holotype PRE!, isotypes K!, W!), syn. nov.

Discussion: —For E. complexa, Dyer (1937) cited only the type specimen, from north-east of Barberton. White et al. (1941) gave the distribution as ‘not further known’ and mentioned that plants flowered from April to June. They discussed the ‘complex nature’ of the inflorescences, by which they meant that each cyme may have as many as five cyathia and each cyathium has five groups of anthers. According to their description, however, the cymes typically consist of three cyathia (only rarely more) and a cyme with three cyathia was depicted in their Plate XIX. Also, the cyathia shown in Plate XIX are typical for members of this complex and have ± sessile ovaries. Fourie (1989) mentioned that it was more widespread than previously known, but no specimens exist from his investigations. Leach made several specimens and extended its known distribution somewhat (PRE records).

In the area of its type locality, E. complexa is distinctive for the yellowish grey-green colour of the fairly slender branches many of which are ± 150 mm long ( White et al. 1941: Plate XIX; see also Fig. 1 A , above), for their weak spines, for their stipular prickles 1.5−3 mm long and for the regular, fairly close spacing of the tubercles. However, this matches specimens such as Kluge 2281 (NBG) from Barberton and the type of E. schinzii . Towards the Swazi and Moçambican border the branches may be much shorter, bluish grey-green, with longer and stouter spines and more separated, more deeply indented tubercles. The presence of relatively prominent stipular prickles 1.5−3 mm long and the identical cyathial structure suggests that these also belong to E. complexa . Their densely branching habit with relatively short branches and weaker spines exclude them from subsp. bechuanica .

A rhizomatous habit was not clearly given for E. complexa by Dyer (1937) or White et al. (1941), who only noted that it branched freely at and below ground-level. However, Leach (1964: 2, 1980: 211) stated that it is rhizomatous.

The flowering time of April to June was mentioned by Fourie (1989), who photographed some plants about to flower. Another collection, Van der Merwe 1947 (PRE), flowered in November 1936. My own collections, made in the area of the type-locality, have flowered in January and February over many years in cultivation. Nevertheless, in habitat, flowering occurs principally between July and September.

Additional specimens examined: — SOUTH AFRICA. 12 miles south of Nelspruit towards Barberton (2530DB), 2400’, Leach & Bayliss 11215 (K, PRE). Hillside farm, Barberton Game Res. (2530DB), Balkwill et al. 9998 (J). Queens River Valley, 22 km from Barberton (2530DD), Balkwill et al. 10213a (J). Ndlopfu waterhole, Crocodile Bridge, KNP (2531BD), Van der Schyff (K). Louw’s Creek (2531CB), Van der Merwe 1947 (PRE). Malelane (2531CB), 1200’, Leach & Jones 12851 (PRE); Rogers 20354 (K, Z). Near Koedoe, on road to Kaalrug (2531CB), 400 m, Bruyns 9390 (BOL). Road from Louw’s Creek to Kaapmuiden (2531CB), Van der Merwe 100 (K, PRE, W). Tonetti (2531CB), 1400’, Leach & Bayliss 11535 (K, PRE). Strathmore 214, west of Malelane (2531CB), Balkwill et al. 9826 (J). Near Kaalrug Mine (2531CB), 380 m, McCleland 827 (BNRH). Berea Ridge, Barberton (2531CC), 3100’, Galpin 1297 (BOL, K). Barberton (2531CC), J. Thorncroft 3112 (PRE). Just outside Barberton towards Havelock Mine (2531CC), 1250 m, Kluge 2281 (NBG). C. 15–20 km south of Komatipoort along border (2531DD), 240 m, J.J. Meyer 2873 (PRE). Mbangwane (2531DD), 350 m, Bruyns 11903 (BOL). Mananga, gravel track off R571, 2.5 km NE of Swazi border (2531DD), 275 m, Turpin et al. 1490 (BNRH). Doornhoek SW, Songimvelo Nat. Res. (2630BB), 980 m, Balkwill 12009 (J). Kromdraai, Songimvelo Nat. Res. (2631AA), 770 m, Balkwill et al. 11030 (J). SWAZILAND. 17 km north of Siteki on road to Mhlume, Lebombo Mtns (2631BD), 1950’, Culverwell 22 (PRE). Sipofaneni (2631DA), 1000’, Compton 29104 (NBG, PRE); Compton 30105 (NBG, PRE); Compton 31942 (NBG). Big Bend, Hlatikulu (2631DD), 500’, Compton 29416 (NBG, NH, PRE). St Phillips Mission (2631DD), Gerstner (NH, PRE). Ingwavuma R. bridge towards Sipofanini (2731BA), 360 m, Bruyns 11854 (BOL).

Figures

FIGURE 1. Tips of branches showing arrangement of tubercles and spine-shields with spines and stipular prickles. A–D, tubercles fused vertically into angles (though fusion of tubercles is the least in D), often with larger stipular prickles (largest inA and B and smallest in D) and spine-shields narrowly elliptic in A and B becoming more narrowly deltate in C and D, E–H, tubercles not fused vertically into angles, with minute stipular prickles and shortly deltate spine-shields, which are especially short in E and G. A, E. schinzii subsp. schinzii, Bruyns 9390 (BOL), ± 8 mm thick. B, E. schinzii subsp. bechuanica, Bruyns 12101 (BOL), ± 10 mm thick. C, E. schinzii subsp. schinzioides, Bruyns 12426 (BOL), ± 8 mm thick. D, E. venteri, Bruyns 12354 (BOL), ± 6 mm thick. E, E. clivicola subsp. clivicola, Bruyns 12115 (BOL), ± 10 mm thick. F, E. clivicola subsp. clivicola, Bruyns 11329 (BOL), ± 6 mm thick. G, E. clivicola subsp. clivicola, Bruyns 13556 (BOL), ± 8 mm thick. H, E. clivicola subsp. calcritica, Bruyns 12045 (BOL), ± 6 mm thick.