Acacia enervia
Acacia enervia is a species of flowering plant in the family Fabaceae and is endemic to the south-west of Western Australia. It is a dense, rounded or conical shrub with slightly angular branchlets, flat, linear to narrowly lance-shaped or terete phyllodes, spherical heads of golden yellow flowers, and linear, thinly leathery pods more or less constricted between the seeds.
Description
Acacia enervia is a dense, rounded or conical shrub with the narrower end towards the base, rarely a small tree, that typically grows to a height of. Its branchlets are slightly angular, glabrous or with soft hairs pressed against the surface. Its phyllodes are inclined to erect, flat and linear to narrowly lance-shaped with the narrower end towards the base, or more or less terete, long and wide. The flowers are borne in up to three spherical heads in leaf axils on peduncles long. Each head is in diameter with 18 to 33 golden yellow flowers. Flowering time depends on subspecies, and the pods are linear, straight or slightly curved, up to long, long, thinly leathery, glabrous and more or less constricted between the seeds. The seeds are narrowly elliptic to oblong, long and black with a white aril on the end.Taxonomy
Acacia enervia was first formally described in 1927 by Maiden & Blakely in the Journal of the Royal Society of Western Australia from a specimen collected by Max Koch on Hines Hill in 1923.This species of wattle is most closely related to A. lineolata and A. inceana that belong to the Acacia enervia group of wattles.
In 1995, Richard Sumner Cowan and Bruce Maslin described two subspecies of A. enervia in the journal Nuytsia, and the names are accepted by the Australian Plant Census:
- Acacia enervia subsp. enervia has more or less terete phyllodes, the flower heads in diameter and flowers mainly in September and October.
- Acacia enervia subsp. explicata R.S.Cowan & Maslin has flat, linear to narrowly lance-shaped phyllodes, the flower heads in diameter and flowers from August to October.
Distribution and habitat
This species of wattle is wide-ranging in the south-west of Western Australia, from north of Dalwallinu to near Lake Grace and Lake Magenta and east to Clear Streak Well, about east-south-east of Norseman.- Subspecies enervia grows in sand, sandy loam or loam, usually in open woodland or open scrub mallee, in the Avon Wheatbelt, Coolgardie and Mallee bioregions.
- Subspecies explicata grows mostly in saline situations around salt marshes, flats and lakes, sometimes in rocky clay on hills, in the Avon Wheatbelt, Coolgardie, Geraldton Sandplains and Mallee bioregions.