A new trap-jawed ant (Hymenoptera: Formicidae: Haidomyrmecini) from Canadian Late Cretaceous amber

Abstract

A new genus and species are described within the extinct tribe Haidomyrmecini, and tentatively placed within the subfamily Sphecomyrminae (Hymenoptera: Formicidae). Haidoterminus cippus new genus and species expands the distribution of the bizarre, exclusively Cretaceous, trap-jawed Haidomyrmecini beyond their previous records in mid-Cretaceous Burmese and French amber, and into Laurentia. The new material from the Grassy Lake, Alberta, Canada collecting locality also provides evidence that these highly specialised, likely arboreal, ants persisted for an additional 20 million years, reaching the Late Cretaceous. Morphological features of H. cippus, such as the presence of an elongate antennomere II (pedicel), further support the argument that Haidomyrmecini may not actually belong within the subfamily Sphecomyrminae, and may warrant recognition at the subfamily level or inclusion as a highly autapomorphic clade within another subfamily. Despite the introduction of new fossil material, and the clarity of preservation in Canadian amber, the mystery of how Haidomyrmecini fed remains unsolved.