Opercularia varia

Opercularia varia, commonly called variable stinkweed, is a small, slender, somewhat fetid-smelling perennial herb or subshrub in the Rubiaceae endemic to south-eastern Australia, occurring in dry sclerophyll forest, heathy woodland and disturbed open ground in New South Wales, Victoria, South Australia and Tasmania. Plants grow 15 to 50 centimetres tall with several wiry, much-branched, erect or ascending, finely ridged stems arising from a slender woody rootstock. The opposite leaves are linear to narrowly oblanceolate, 0.5 to 2.5 centimetres long, with revolute margins and an unpleasantly musky scent when bruised; the interpetiolar stipules characteristic of the family are reduced to fringed sheaths uniting the leaf bases. Small flowers are aggregated into compact, sessile, button-like heads 4 to 8 millimetres across borne in the upper leaf axils and at the stem tips; each head consists of several four-merous tubular greenish-yellow to brownish flowers fused at the base, the perianth opening by means of a distinctive lid-like calyx that gives the genus its name. The fruit is a small dry indehiscent nutlet.