Dilophus has many named species in Australia and are characterised by having tubercles and bristles on the prontum. There are photos on iNaturalist and ALA. Using Hardy (1982) The Bibionidae (Diptera) of Australia (Aust J Zool 30:805-55), we have settled on longirostris because of the long rostrum, hyaline wings, location and size of tibial spines, colour of the thorax and geographic distribution..