New ants (Hymenoptera: Formicidae: Dolichoderinae) from Canadian Late Cretaceous amber

Abstract

A new genus and species are described within the ant subfamily Dolichoderinae (Formicidae). Chronomyrmex medicinehatensis gen. et sp. nov. McKellar, Glasier & Engel provides a solid example of Dolichoderinae within the Campanian Grassy Lake amber of southern Alberta (Late Cretaceous, 78-79 Ma). The new species fills a void in the dolichoderine fossil record left by Eotapinoma canadensis Dlussky, a putative dolichoderine whose taxonomic placement has been questioned, and whose type material has been lost. As such, C. medicinehatensis provides a constraint for divergence times of the subfamily and Leptomyrmecini, one of its recently resurrected tribes. This discovery greatly extends the proposed divergence time for Dolichoderinae, and likely Leptomyrmecini, to more than 78 Ma -contrary to some of the more recent estimates inferred from molecular phylogenies.