Prophaenognatha robusta gen.et sp.nov.(Scarabaeoidea:Scarabaeidae:Aclopinae),the best-preserved aclopine fossil so far,is described and illustrated from the Upper Jurassic-Lower Cretaceous Yixian Formation of the Jehol Biota,western Liaoning Province,NE China.The key to extinct and extant genera of Aclopinae is given and the monophyly of extant and fossil Aclopinae lineages is supported by five character states.The new taxon provides evidence about the evolution of Scarabaeoidea with its phylogenetic position inferred based on 68 morphological characters.
