Acacia ryaniana

The prostrate spinescent shrub typically grows to a height of 0.1 to 0.4 metres (0.3 to 1.3 ft).^[1] It normally has glabrous branchlets that are often covered with a white powdery coating and have spinose stipules with a length of 2 to 6 mm (0.079 to 0.236 in). Like most species of Acacia it has phyllodes rather than true leaves. The evergreen phyllodes have an ovate to narrowly elliptic shape with a length of 12 to 25 mm (0.47 to 0.98 in) and a width of 7 to 15 mm (0.28 to 0.59 in). The glabrous and coriaceous phyllodes have a single main nerve and are finely penninerved.^[2] It blooms from June to November and produces yellow flowers.^[1] It has simple inflorescences that are found singly in the axils with spherical flower-heads that have a diameter of around 10 mm (0.39 in) containing 60 to 70 densely packed golden coloured flowers. The chartaceous, light brown or yellow-brown coloured seed pods that form after flowering are curved and rounded over the seeds. The glabrous pods are up to 8 cm (3.1 in) in length and 10 to 18 mm (0.39 to 0.71 in) with the seeds arranged transversely to obliquely inside. The shiny dark-brown seeds have a spherical to broadly elliptic shape and a length of 5 to 6 mm (0.20 to 0.24 in) and are often paler toward the centre with a narrow aril.^[2]

The species was first formally described by the botanist Bruce Maslin in 1992 as part of the work Acacia Miscellany. Review of Acacia victoriae and related species (Leguminosae: Mimosoideae: Section Phyllodineae) as published in the journal Nuytsia. It was reclassified as Racosperma ryanianum in 2003 by Leslie Pedley then transferred back to genus Acacia in 2006.^[3] The shrub belongs to the Acacia victoriae group but can be distinguished by its prostrate habit and curved pods.^[2]