Acacia quinquenervia

The shrub typically grows to a height of 0.2 to 1.5 metres (0.7 to 4.9 ft) with peeling and fibrous bark.^[1] The branchelts are usually densely haired and like most species of Acacia it has phyllodes rather than true leaves. The green to grey-green phyllodes are flat with a narrowly linear shape with a length of 2 to 7 cm (0.79 to 2.76 in) and a width of 1 to 2 mm (0.039 to 0.079 in) with five noticeable nerves. The rudimentary inflorescences appear on two branched racemes with spherical flower-heads that have a diameter of 3.5 to 4 mm (0.14 to 0.16 in) and contain 15 to 20 light golden coloured flowers. The linear and biconvex seed pods that form after flowering are shallowly curved and have a length up to around 5.5 cm (2.2 in) and a width of 1.5 to 3 m (4 ft 11 in to 9 ft 10 in). The thinly coriaceous-crustaceous seed pods are glabrous to moderately hairy with longitudinally arranged seeds inside. The mottled seeds have an oblong shape with a length of 2.5 to 3 mm (0.098 to 0.118 in) and a terminal conical shaped aril.^[2]

The species was first formally described by the botanist Bruce Maslin in 1999 as part of the work Acacia miscellany. The taxonomy of fifty-five species of Acacia, primarily Western Australian, in section Phyllodineae (Leguminosae: Mimosoideae) as published in the journal Nuytsia. It was reclassified as Racosperma quinquenervium by Leslie Pedley in 2003 then transferred back to genus Acacia in 2006.^[3] The specific epithet (quinquenervia) is from the Latin quinque meaning "five" and nervus, "vein", referring to the leaves usually having five veins.^[4]