Four species of the genus Thelotrema containing the norstictic acid chemosydrome are accepted in Australia: T. bicavatum Nyl., T. porinaceum Müll. Arg. and the new species T. gallowayanum and T. eungellaense. T. bicavatum, formerly regarded as a synonym of T. subtile Tuck. is shown to be a independent species. The species are described, their distribution is mapped and a key for the identification is provided