A new genus of hell ants from the Cretaceous (Hymenoptera: Formicidae: Haidomyrmecini) with a novel head structure Phillip Barden Hollister W. Herhold David A. Grimaldi Systematic Entomology 2017 42 837 846 Dlussky 1996 [187,322,1147,1168] Insecta Formicidae Haidomyrmex GBIF Animalia Hymenoptera 1 838 Arthropoda genus    HaidomyrmexzigrasiBarden & Grimaldi – reconstructions based on two entirely complete dealate ( H. scimitarus) and worker ( H. zigrasi) specimens suggested that the enigmatic L-shaped mandibles probably articulated, at least partially, in a vertical plane. In particular, the placement of trigger hairs on the clypeus as well as the hypognathous-like orientation of the head (all other non-haidomyrmecine ant heads are prognathous; Keller, 2011) suggested that hell ants were Cretaceous analogues to modern trap-jaw predators ( Barden & Grimaldi, 2012). H. scimitarusis also the largest haidomyrmecine, measuring over twice the total length of most other species.  Locality: Burmese amber