Opercularia aspera

Opercularia aspera, commonly called coarse stinkweed, is a small perennial herb to subshrub in the Rubiaceae family, endemic to southern and eastern Australia. The plant forms a low, often straggling clump with slender, somewhat woody stems arising from a perennial rootstock. Leaves are opposite, ovate to elliptic with a rough surface and entire margins, typically 1 to 3 cm long, joined at the base by interpetiolar stipules that are characteristic of the family. Small greenish-yellow to dull yellow flowers are aggregated into compact terminal heads of several florets fused at the base, producing the distinctive operculate fruiting structure that gives the genus its name. The plant occurs in dry sclerophyll forest, woodland and disturbed ground on a range of soils across Victoria, New South Wales, southern Queensland, South Australia, Tasmania and parts of Western Australia, where it can become locally weedy.