Senegalia senegal var. leiorhachis prickles

The thorns of Senegalia senegal var. leiorhachis, the Senegalia version of stipules, grow in threes just below each leaf node. More prickle than spine, they are hard and sharp with pointed tips that curve just slightly. The centre prickle of each group of three is angled differently, usually down, the lateral pair point slightly upwards.

The young branches lack the peeling bark of old stems, this hanging one still smooth and pale grey. The youngest branchlets of this tree are variously coloured (some brown or olive-green), sometimes even hairy with scattered lenticels upon the surface (Coates Palgrave, 2002; Van Wyk and Van Wyk, 1997; Schmidt, et al, 2002; iNaturalist).