myrmecophile, myrmecophilous, myrmecophily

From Greek murmex (μυρμηγξ) ant, plus suffix -phile, a Latinized version of Greek philos (φιλος) dear, beloved (Wiktionary).

myrmecophile noun, adjective myrmecophilous - an organism, especially an insect or other arthropod, that lives in close association with or shares a nest with a species of ant--Formicidae (Wiktionary). Myrmecophily refers to the phenomenon of ant association in general. Examples are known from several groups:

Quoting the summary from Wikipedia:

Myrmecophiles may have various roles in their host ant colony. Many consume waste materials in the nests, such as dead ants, dead larvae, or fungi growing in the nest. Some myrmecophiles, however, feed on the stored food supplies of ants, and a few are predatory on ant eggs, larvae, or pupae. Others benefit the ants by providing a food source for them. Many myrmecophilous relationships are obligate, meaning one or the other participant requires the relationship for survival. Some associations are facultative, benefiting one or both participants but not being necessary to their survival.

Some photos of myrmecophilous species: