Vachellia etbaica (Schweinf.) Kyal. & Boatwr.
Acacia etbaica Schweinf.
Eng.: Savanna thorn. Spa.: Acacia. Ara.: Arrad, qarad.
Tree up to 12 m in height, spiny, hermaphrodite, deciduous, with straight trunk or multi-stemmed, crown rounded or umbrella-shaped. Trunk and main branches with bark smooth or rugose and fissured, brown or brown-black, which does not peel. Young branches greyish-brown or brown-purplish, glabrous or puberulous. Stipular spines paired, divergent, brownish or whitish; of 2 types, some small (0.3-0.7 cm), hooked, and others much larger (up to 6 cm), straight or curved. Leaves 3-6.5 cm, alternate, bipinnate, with petiole 0.3-1.5 cm, petiole and rachis eglandular, the latter with 1-9(17) pairs of pinnae, each with 4-35 pairs of leaflets 0.5-4 × 0.2-1.3 mm, oblong, rounded at the apex, subsessile, glabrous or puberulous, green. Inflorescences in spherical capitula, 5-9 mm in diameter, axillary, solitary or in fascicles of 3-5, pedunculate —peduncle 0.7-4 cm, puberulent—, with numerous minute flowers, white or cream. Calyx 0.4-1 mm, with puberulous teeth. Corolla 2-3 mm. Stamens numerous. Pod 2-12 cm × (7)15-22 mm, linear, pendulous, straight, not constricted between the seeds, compressed, brown or purple or reddish-brown, shiny, glabrous or puberulous towards the base, dehiscent with 6-8 seeds. Seeds 5.5 × 3.5-8 mm, ellipsoid to suborbicular, compressed, brown or an olive brown, smooth.
Flowering:
August to November.
Fruiting:
January to May.
Habitat:
Savannahs and thickets in semidesert environments.
Distribution:
Eastern Africa (from SE Egypt to the N of Tanzania) and Arabian Peninsula.
Observations:
A highly polymorphic species, for which various subspecies have been described.
Conservation status:
A relatively common and widespread species, not considered threatened. In the IUCN Red List of Threatened Species, it is listed as Least Concern (LC) at global level. In the updated red list of Egypt (Shaltout & Bedair, 2023) it has been considered as Vulnerable (VU).