See text Haidomyrmecinae, occasionally called hell ants, are an extinct subfamily of ants (Formicidae) known from Cretaceous fossils found in ambers of North America, Europe, and Asia, spanning the late Albian to Campanian, around 100 to 79 million years ago.

The jaws in combination with the head ornamentation served to restrain prey, with most species having setae (hair-like structures) covering parts of the head, which likely functioned as triggers to rapidly close the jaw when disturbed, similar to those of modern trap-jaw ants.

[2] Like modern ants, they were eusocial, with distinct worker and queen castes,[2] likely with relatively small colony sizes.

[3] Due to their lack of metabolic stores, the queens likely engaged in hunting during the initial foundation of the nest.

The vast majority of species are known from Burmese amber, which dates to the mid-Cretaceous, around 100 million years ago.