Department of Primary Industries, Parks, Water and Environment, Hobart, 2011
Scientific name: Spyridium obcordatum (Hook.f.) W.M.Curtis, Vict. Nat. 87: 251 (1970)
Common Name: creeping dustymiller (Wapstra et al. 2005)
Group: vascular plant, dicotyledon, family Rhamnaceae
Status: Threatened Species Protection Act 1995 (TSP Act): vulnerable
Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act): Vulnerable
Distribution: Endemic status: Endemic to Tasmania
Tasmanian Natural Resource Management (NRM): Cradle Coast, North
Description and taxonomy
Spyridium obcordatum, commonly known as creeping dustymiller, is a prostrate shrub with a thickening at the base of the main stem from which numerous branches arise. The branches are generally up to 40 cm long and are brittle and wiry with chestnut coloured wood. The branches tend to spread along the ground or trail over embankments or between rocks. The leaves are indented at the tip (obcordate) with an indented mid-rib and recurved margins, and are up to 10 mm long. The upper leaf surface is bright green and glossy and the lower surface is white with a covering of short hairs. The flowers are small and white, about 3 mm wide, and are organised in tight clusters that are surrounded by brown bracts and floral leaves (leaves that look like petals). The seeds are hard, light brown and 1.0 to 1.5 mm in size.
Spyridium obcordatum is superficially similar to Spyridium lawrencei (small-leaf dustymiller) and Stenanthemum pimeleoides (propeller plant) but does not occur within the range of these eastern Tasmanian species. It can be identified at any time of the year.
Spyridium is a genus in the Rhamnaceae, a family represented by eighteen genera in Australia, five of which are native to Tasmania, namely Cryptandra, Discaria, Pomaderris, Spyridium and Stenanthemum (Buchanan 2007). There are ten Spyridium taxa in Tasmania, seven of which are endemic to the state. Six Spyridium taxa are currently listed on the TSP Act, and two of these, Spyridium lawrencei and Spyridium obcordatum, are also listed on the EPBC Act.