A new marattialean fern from the Middle Triassic of eastern Australia

The marattialean genus Marantoidea Jaeger is revised, and Danaeopsis Heer is shown to be a junior synonym of Marantoidea. Of the species formerly assigned to Danaeopsis, those that can be confirmed as marattialean are transferred to Marantoidea; many of the others are probably pteridosperms. The new species Marantoidea acara is described from the Middle Triassic Toogoolawah Group and Nymboida Coal Measures of eastern Australia. It is distinguished by the small size of its sporangia. The Triassic distribution of marattialeans in Gondwana indicates that these ferns had a similar temperature preference in the past to that today, and have probably had a megathermal-mesothermal distribution throughout their history.