Origin and Habitat: Chad, Sudan, Ethiopia and Egypt (Nubia).
Type locality: Sudan, Dar Foq Soudan Orient., Atlas
Altitude range: Around 1200-1220 metres above sea level.
Habitat: Stony slopes in dry grassland with scattered trees. Locally abundant. Arid hills and open rocky hillsides with Combretum.

• Euphorbia venenifica Trémaux ex Kotschy
• Euphorbia venefica Trémaux ex Kotschy

Description: Euphorbia venenifica (originally published as Euphorbia venefica, an incorrect orthographic variant) is a stout,erect succulent bush or cactus-like tree 2-5(-6) m high, branching from a short thick stem into a few or several cylindrical main stems, topped with large, prominently veined leaves during the growing season, occasionally sub-spiny. The stems occasionally rebranches loosely in an irregular manner. It produces small, lime yellow-green flowers in spring.
Branches: Spreading-ascending, fleshy, cylindrical, to 3.5 cm. thick, green to pale grey on old trees, smooth, glabrous, full of white latex.
Spine-shields: Approx 1 cm. apart in about 8 spiral series, obtusely triangular to subcircular, 6-8 mm. in diameter, surmounted by a rudimentary, single spine (sometimes absent or present only on young plants), much dilated or flattened at the base. The spine end abruptly at its dilated base, but not extends into the suborbicular shield, somewhat blackish, 3-8(-15) mm long. So it would appear E. venenifica can be spineless or have one spine.
Leaves: Alternate, sessile, deciduous, pale green, somewhat glaucous at base, spirally-arranged or in 8-10 ranks at the apex of the branches, glabrous, somewhat fleshy, green and somewhat glaucous base, variable in size and shape from lanceolate to spatulate or obovate, 4-22 cm long, 1-4 cm wide, apex acute, truncate or occasionally emarginate, apiculate, margin entire, often minutely crisped. Nerves Pinnate, only the midrib is clearly visible. For the most part of year the plant is leafless, only leafing for two or three months, during the rainy season.
Inflorescence (cymes): Solitary set on the upper edge of a leaf scar immediately above the spine-shields, 1-2-forked, with peduncles and cyme-branches about 7 mm long. Bud trigonous. Bracts rounded, approx 2.5 x 4 mm.
Flowers (cyathia): 2.5 x 5 mm, with cup-shaped involucres; glands transversely oblong, approx 1 x 2.8 mm, contiguous, yellowish green; lobes subcircular, a 1.5 mm. diameter.
Male flowers: bracteoles spathulate, deeply laciniate; stamens 3.75 mm. long.
Female flower: styles 1.5 mm. long, joined at the base, apices much thickened.
Blooming season: It flowers at the end of the dry season, before coming into leaf.
Fruits (capsules): Exserted on a reflexed pedicel to 5 mm. long, distinctly 3-lobed, more or less globose, approx 4 x 6 mm, buff, grey or beige when ripe and glabrous.
Seeds: Subglobose, 2.5 mm. in diameter, buff, mottled, smooth.
Related species: Euphorbia venenificaSN|21556]]SN|28017]] Trem. is strictly related and often synonymized with Euphorbia poissonii Pax and Euphorbia unispina N.E.Br. Its leaves look like those of Euphorbia desmondii Keay & Milne-Redh., whose branches are angular, 3-5 sided and non-cylindrical. It is also related to Euphorbia sudanica Chev., Euphorbia nivulia Buch.-Ham. (India), Euphorbia neriifolia L. (India), Euphorbia qarad Defl. (Arabia), Euphorbia amicorum, Euphorbia deciduaSN|28017]]SN|21556]], Euphorbia imitata, and Euphorbia brevis.

Bibliography: Major references and further lectures
1) A. R. Smith, Susan Carter “Flora of Tropical East Africa - Euphorbiacee” volume 2 (1988) CRC Press, 01/giu/1988
2) Michel Arbonnier "Trees, Shrubs and Lianas of West African Dry Zones" Editions Quae, 2004
3) Hans Dieter Neuwinger “African Ethnobotany: Poisons and Drugs : Chemistry, Pharmacology, Toxicology” CRC Press, 1996
4) Georg August Schweinfurth “The heart of Africa: three years' travels and adventures in the unexplored regions of Central Africa from 1868 to 1871” Volume 1 Gregg, 1969
5) “Medicinal Plants” Volume 1 PROTA, 2008
6) Werner Rauh “The Wonderful World of Succulents: Cultivation and Description of Selected Succulent Plants Other Than Cacti” Smithsonian Institution Press, 1984
7) William Julius Eggeling “The Indigenous Trees of the Uganda Protectorate” Government Printer, South Africa, 1940
8) Hermann Jacobsen “Abromeitiella to Euphorbia” Blandford Press, 1960
9) Urs Eggli “Illustrated Handbook of Succulent Plants: Dicotyledons” Springer, 2002

Cultivation and Propagation: Very slow growing and cold sensitive species can to grow in both pots and in the ground in areas with mild climate, but they can even be grown indoors. Sun Exposure: Light shade. They grow well in a very draining mineral potting substrate. During the summer, they enjoy average feeding and watering. When dormant, plants are relatively cold tolerant.
Propagation: Usually by seeds, it can also It be propagated by cuttings; if you remove an offset, remember to let it dry for a week or so, letting the wound heal (cutting planted to soon easily rot before they can grow roots). It is better to wash the cut to remove the latex.
Traditional uses:
Edges: Often planted as hedgerows around fields and cemeteries (animal pens, fencing to prevent cattle roaming, boundary marking)
Flowers: Liked by bees and many other insects. Apiculture.
Poison: Latex Poison for hunting', fishing and criminal purposes (cow milk is said to be the antidote), birdlime.
Warning: When a plant get damaged it exudes a thick white milky sap known as latex. This latex (resin) is poisonous contains some of the most potent irritants known. The latex is particularly dangerous for the eyes, skin and mucous membranes. So pay extreme attention not to get any in your eyes or mouth. Cultivated plants must be handled carefully.