Compilation
Euphorbia columnaris

Succulent perennial with a solitary stem erect to 1 m high; roots fibrous. Stem branching only when damaged at the apex, terete, 5–8 cm thick, 13–17-angled; angles separated by deep grooves, sinuately toothed, with teeth 5–15 mm apart. Spine-shields oblong-triangular, 5–14 x 3–6 mm, the ridges (angles) hardening around them to form a pale yellowish margin along the angles, enclosing the flowering eye above and usually decurrent below; spines present only on early seedling growth; prickles (modified stipules) developed into strong spines 8–18 mm long, curved outwards, joined at the base into a short column 1–2 mm high and with the leaf-scar between them. Cymes crowded 10–30 at each flowering eye, maturing successively in groups of 2–6, 1-forked, with peduncle and cyme-branches 3–7 mm long. Cyathia 3 mm in diam.; glands 1.5 mm broad, touching, golden yellow. Stamens well exserted. Ovary exserted on a recurved pedicel, obtusely 3-lobed; styles 2 mm long with shortly bifid apices. Capsule and seeds not seen.