Parelateriformius from the Middle–Late Jurassic of China reinterpreted as the earliest Dascillidae (Coleoptera: Dascilloidea)

The elateriform genus Parelateriformius Yan & Wang from the Middle–Late Jurassic Daohugou beds has been placed previously in the extinct Lasiosynidae or the extant Eulichadidae. Our reinvestigation of the type specimens and additional materials suggests that the character combination of Parelateriformius (e.g., tarsomeres 2–4 distinctly lobed, posterior pronotal margin crenulate, radial cell short and with truncate base, and metakatepisternal suture complete) is not accordant with either Lasiosynidae or Eulichadidae. Instead, it should belong to the family Dascillidae and appears closely related to the extant Petalon. A new species of Parelateriformius is also described, as P. grimaldii Li & Cai sp. nov. Our discovery highlights the antiquity of Dascillidae, which is consistent with the recent fossil-calibrated molecular dating of beetles.