Acacia orthotropica, commonly known as Mount Trafalgar wattle,[1] is a shrub of the genus Acacia and the subgenus Plurinerves that is endemic to north western Australia.
The single-stemmed tree can grow to a height of around and has an obconic habit with glabrous red-brown coloured branchlets. Like most species of Acacia it has phyllodes rather than true leaves. The thinly leathery, erect, crowded and evergreen phyllodes have a narrowly oblong-oblanceolate shape and are quite straight with a length of and a width of with two longitudinal nerves. It blooms around January and produces simple inflorescences found in the axils and made up of spherical flower-heads containing 30 to 35 light golden coloured flowers.[1]
It is native to a small area in the Kimberley region of Western Australia. The limited distribution is confined to a single population within the confines of the Prince Regent National Park where it is a situated on a slope of broken sandstone slope next to a low basalt hill where it is part of an open shrubland community associated with a groind cover of species of Triodia.[1]