Acacia diallaga (Leguminosae: Mimosoideae), a new geographically restricted species with diallagous phyllodes from the Midwest Region of south-west Western Australia

Abstract

Acacia diallaga Maslin & Buscumb, a new species of Acacia sect.Juliflorae (Benth.) C.Moore & Betche restricted to a small area east of Morawa in the Midwest Region of Western Australia is described. A feature of the new species (and one from which the botanical name is derived) is that during times of drought the phyllodes turn a purplish colour, reverting to their normal glaucous to sub-glaucous colour when conditions improve. This process of foliage colour change related to weather conditions occurs also in A. subsessilis A.R.Chapman & Maslin which is the closest relative of A. diallaga. The new species is listed as a Priority Two species according to the Department of Environment and Conservation’s Conservation Codes for Western Australian Flora.