Pimelea spinescens is a spreading, stunted, long-lived undershrub that typically grows to a height of 5–30 cm (2.0–11.8 in).

[3][4][5] Pimelea spinescens was first formally described in 1988 by Barbara Lynette Rye in Flora of Australia from specimens collected by Neville Scarlett near Myers Creek, (north of Healesville) in 1980.

[6] In the same publication, Rye described two subspecies of P. spinescens, and the names are accepted by the Australian Plant Census: Subspecies pubiflora was thought to be extinct since it had not been collected since 1901, but was rediscovered in 1980, growing in grassy woodland in the Wimmera region of Victoria.

[9] Subspecies spinescens grows mainly in grassland and open shrubland between Melbourne, Horsham and Echuca.

[9][11] The main threats to the species include habitat loss and fragmentation, inappropriate fire regimes, weed invasion, and grazing by feral herbivores and livestock.