摘要

dagger Praphennium gen. nov. is described to include dagger Praphennium carinatum sp. nov. from the Cenomanian Myanmar amber. Two other species are placed in the same genus, but they remain unnamed. This is the first known extinct genus of the large tribe Cephenniini that includes cosmopolitan extant ant-like stone beetles with uniquely modified mouthparts adapted to feed on armored mites. dagger Praphennium shares most exoskeletal characters with its extant relatives, and the structure and position of its hypognathous head suggest that the adults were also specialized predators that fed on heavily sclerotized oribatid or uropodine mites. One of the studied specimens seems to be teratological, with a reduced number of antennomeres, representing the first such a case in the fossil record of Scydmaeninae. Together with a previously known Turonian dagger Hyperstenichnus of Glandulariini, the discovery of dagger Praphennium supports early origins of acarophagy among Scydmaeninae, the only group of beetles that have adapted to feeding on this well-protected group of soil arthropods. A preliminary phylogenetic analysis suggests a close relationship between dagger Praphennium and the extant genera Cephennodes and Hlavaciellus, and this Glade might have likely evolved within the Eurasian part of Laurasia.

  • 出版日期2018-10