Vachellia
Vachellia Wight & Arn., in Prodr. Fl. Ind. Orient.: 272 (1834).
Trees or shrubs, sometimes climbing; the native species in our area almost invariably armed with prickles or spines, the introduced ones usually unarmed, Leaves 2-pinnate or (in introduced species) often modified to phyllodes (entire leaflike often flattened organs without pinnae or leaflets); pinnae each with one to many pairs of leaflets; gland on the upper side of the petiole usually present; glands also often present at the insertion of the pinnae, Flowers in spikes, spiciform racemes or round heads, hermaphrodite or male and hermaphrodite; if in heads then central flowers not enlarged and modified; inflorescences usually axillary, racemose or paniculate, Calyx (in our species) gamosepalous, subtruncate or usually with 4-5 teeth or lobes, Corolla 4-5(7)-lobed, Stamens many, fertile, their filaments free or (in A. albida and A. eriocarpa) connate into a tube at their extreme base only; anthers (at least some) glandular at the apex, or all eglandular (in all native species glandular except in A. albida, in introduced species mostly eglandular), Ovary stipitate to sessile, glabrous to puberulous, Pods very variable, dehiscent or sometimes indehiscent, flat, ± compressed, or sometimes cylindric, straight, curved, spiral or contorted, continuous or moniliform, Seeds unwinged, often with a hard smooth testa, without endosperm.
Its native range is Tropics & Subtropics.