Compilation
Acacia formicarum

Bush or small tree 1–5(–7.5) m. high, with short radiating branches from main stem, sometimes spreading at top. Young branchlets shortly pubescent to puberulous, rarely glabrous, grey then going brown; no powdery inner bark on twigs. Old bark black or grey, usually rough, sometimes smoothish. Stipules spinescent, mostly 1.5–4.5(–7.5) cm. long (some shorter ones often also present), straight, grey or whitish, some fused at base into ± round “ant-galls” 1–3.5 cm. in diameter, grape-purple going blackish. Leaves: petiole 2–5 (very rarely to 10) mm. long, glandular at the lowest of the 3–13 pairs of pinnae; rhachis 0.8–4.5(–9) cm. long, glandular between the top 1–6 pairs of pinnae; leaflets 11–22 pairs, glabrous or minutely ciliolate, subacute or acute sometimes obtuse at apex, 1.5–5.5 mm. long, 0.7–1.25 (–1.75) mm. wide. Flowers white or sometimes cream, in heads; involucel at or rarely a short way above base of the glabrous puberulous or shortly pubescent peduncle. Calyx 0.75–1.5(–2.5) mm, long, glabrous or ciliolate. Corolla glabrous outside, sometimes puberulous on lobes, 3–4 mm. long. Pods (Fig. 16/48, p. 67) falcate or annular, thinly coriaceous, finely longitudinally venose, glabrous or ± puberulous, mostly attenuate or even acuminate at ends, 4–7 cm. long, 0.5–1.0 cm. wide. Seeds mottled whitish-grey and dark brown, smooth, irregularly quadrate or elliptic, compressed, 10–12 mm. long, 4.5–5.5 mm. wide; areole 5–6 mm. long, 3–3.5 mm. wide.