Myrmecophily ( , ) is the term applied to positive interspecies associations between ants and a variety of other organisms, such as plants, other arthropods, and fungi. Myrmecophily refers to mutualistic associations with ants, though in its more general use, the term may also refer to commensal or even parasitic interactions.
The term "myrmecophile" is used mainly for animals that associate with ants. An estimated 10,000 species of ants (Formicidae) are known, with a higher diversity in the tropics. In most terrestrial ecosystems, ants are ecologically and numerically dominant, being the main invertebrate predators. As a result, ants play a key role in controlling arthropod richness, abundance, and community structure. Some evidence shows that the evolution of myrmecophilous interactions has contributed to the abundance and ecological success of ants, by ensuring a dependable and energy-rich food supply, thus providing a competitive advantage for ants over other invertebrate predators. Most myrmecophilous associations are opportunistic, unspecialized, and facultative (meaning both species are capable of surviving without the interaction), though obligate mutualisms (those in which one or both species are dependent on the interaction for survival) have also been observed for many species.
As ant nests grow, they are more likely to house more and greater varieties of myrmecophiles. This is partly because larger colonies have greater specializations, so more diversity of ecology within the nests, allowing for more diversity and population sizes among the myrmecophiles.
Myrmecophile
A "myrmecophile" is an organism that lives in association with ants.
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. Most associations are facultative, benefiting one or both participants, but not being necessary to their survival, but many myrmecophilous relationships are obligate, meaning one or the other participant requires the relationship for survival.
Myrmecophilous associations are best known in butterflies of the family Lycaenidae. Many lycaenid caterpillars produce nectar by specialized organs, and communicate with the ants through sound and vibrations. The association with ants is believed to reduce the parasitisation of the butterfly caterpillars.
Some myrmecophilous beetles are in the families Coccinellidae (e.g. the ladybird Thalassa saginata), Aphodiidae, Scarabaeidae, Lucanidae, Cholevidae, Pselaphidae, Staphylinidae, Histeridae, and Ptiliidae (some treated here as subfamilies). In ant-beetle associations, the myrmecophilous staphylinids are the most diverse of the beetle families. Myrmecophilous associations are also seen in various other insects, such as aphids and treehoppers, as well as the hoverfly genus Microdon and several other groups of flies.
Ant nests provide environmentally stable environments that are well organized and protected by the host colony. The benefit of ant colonies has resulted in infiltration from a variety of myrmecophiles. The ant guests can have a positive, neutral, or negative effect on the colony. If the infiltrating species' impact is too negative on the colony, they risk discovery; this usually results in relatively small populations of myrmecophiles. Some spider species will use traits such as myrmecomorphy – ant mimicry - and chemical mimicry to infiltrate ant nests, usually to prey on food supplies or the ants themselves. Aribates javensis, a species of oribatid mites, is an obligate myrmecophile that lives in ant nests. These mites are cared for by their ant hosts in exchange for eating litter and bacteria in the nest.
Other myrmecophile groups include: Orthoptera, such as the cricket Myrmecophilus acervorum Diptera, such as the stratiomyid fly Clitellaria obtusa Blattodea, such as the Attaphila cockroaches Molluscs, such as Allopeas myrmekophilos
The first major work in cataloguing British myrmecophiles was done by Horace Donisthorpe in his 1927 book The Guests of British Ants.