A review of the trunk-boring cycad weevils in Australia, with description of a second species of Demyrsus Pascoe, 1872 (Coleoptera: Curculionidae)

The Australian trunk-boring cycad weevils of the genera Demyrsus Pascoe, 1872 and Siraton Hustache, 1934 (Molytinae) are sometimes considered as cycad pests when they infest planted cycads and can be transported to other countries. In the present study, the taxonomy of Demyrsus and Siraton is reviewed, and four species are recognised: D. meleoides Pascoe, 1872, D. digmon sp. nov., S. internatus (Pascoe, 1870) and S. roei (Boheman, 1843). The discovery of a second species of Demyrsus illustrates a larger diversity of cycad-associated weevils in Australia than currently known and identifies a further species with the potential to damage and kill cultivated cycads. The species descriptions and diagnoses are supplemented with illustrations of the habitus and salient structures, a distribution map and an identification key to all species of trunk-boring cycad weevils in Australia. Their potential hosts are identified from a spatial analysis of their distributions and the distributions of the cycad taxa occurring in this range.