Acacia dorsenna


Acacia dorsenna is a species of flowering plant in the family Fabaceae and is endemic to a restricted region of inland Western Australia. It is a dense, domed, glabrous shrub with elliptic to egg-shaped phyllodes, spherical heads of bright, mid-golden yellow flowers and narrowly oblong pods rounded over the seeds.

Description

Acacia dorsenna is dense, domed, glabrous shrub that typically grows to a height of and up to wide. Its phyllodes are elliptic to egg-shaped with the narrower end towards the base, with a markedly convex upper margin long and with a small gland above the base of the phyllode. The flowers are borne in seven to ten spherical heads in racemes long, the heads on peduncles long, each head with 15 to 21 bright mid-golden yellow flowers. Flowering has been recorded in August and September, and the pods are narrowly oblong, up to long and wide, brown, firmly papery, and conspicuously rounded over the seeds. The seeds are oblong-elliptic, of up to long with a small aril.
It is a member of the A. prainii group and resembles A. camptoclada and some forms of A. merrallii.

Taxonomy

Acacia dorsenna was first formally described in 1995 by Bruce Maslin in the journal Nuytsia from specimens he collected north of Norseman in 1986. The specific epithet means 'humpbacked', "alluding to the predominantly rounded upper margin of the phyllodes".

Distribution and habitat

This species of wattle grows in red-brown, rocky, sandy loam or clayey loam and is only known from two populations about north of Norseman in the Coolgardie bioregion of inland Western Australia.

Conservation status

Acacia dorsenna is listed as "Priority One" by the Government of Western Australia Department of Biodiversity, Conservation and Attractions, meaning that it is known from only one or a few locations that are potentially at risk.