Euphorbia bivonae Steudel.
Eng.: Spurge. Spa.: Lechetrezna, tabaiba. Fre.: Euphorbe de Bivona. Ara.: Lezara.
Monoecious shrub, up to 1-1.50 m in height, upright-hemispherical bearing in drier places, with sparse foliage. Stems ramose almost from the base. Bark is brown in older stems and branches and green or reddish on young branchlets. Leaves (25-70 × 5-20 mm), loosely arranged (concentrating only slightly at the end of the branchlets), lanceolate, oblong or obovate, obtuse or slightly acute, with entire margin and gently undulate, glabrous, with a slightly lighter green on the underside. Pleiochasium with 3-5 bifurcated rays. Dichasial bracts ellipsoid or broadly obovate, greenish. Pleiochasial bracts similar, but sometimes almost twice the size, more like leaves. Male and female flowers appear together in a cyathium. Cyathia 2.5-4 mm, subsessile or shortly pedunculate. Nectaries reddish. Fruit a globose capsule, 4-5.2 × 4.2-5.5 mm, with grooves between shallow cocci. Surface of the cocci covered by numerous warts. Seed (3 × 2 × 1.7 mm) oblong to ovoid, slightly compressed, with a smooth surface and generally brown, carunculate.
Flowering:
February to April.
Fruiting:
April to May.
Habitat:
Cleared thickets in between rocky outcrops, generally in coastal and subcoastal areas.
Distribution:
In Sicily and Malta, central North Africa (from the Oran region to the Cyrenaica). It is common in this coastal strip, growing scattered around in almost all areas ± close to the sea. Further inland it becomes rarer; in Algeria it reaches towards the S to the Saharan Atlas and in Tunisia and Libya it penetrates semidesert areas, in clearly continental areas such as the mountains of Gafsa and Matmatas (Tunisia) and Nafusa (Libya).
Observations:
Plants of the Saharan region of Tunisia (Gafsa and around Chott el Djerid) and the adjacent Algerian regions (reaching Chott Melrhir), as well as the Cyrenaica (Libya) have been segregated into a separate subspecies: E. bivonae subsp. tunetana Murb. (E. bivonae var. papillaris Boiss.). They are differentiated by having shorted branchlets and wider warts (hemispherical in shape), as opposed to narrowed papillae (cylindrical in shape) of the type subspecies.
Conservation status:
A relatively common species with a wide distribution. It is not considered threatened. Currently, it has not been assessed at a global level in the IUCN Red List of Threatened Species. In the Livre Rouge de la flore vasculaire du Maroc (Fennane, 2021) it has been considered as Not applicable (NA).
