Abstract: | A comprehensive and critical review of all available literature on associations between Australian lycaenid butterflies and ants was undertaken to establish an accurate database of the partners involved. Collections and observations of lycaenids and ants were used to augment this review, resulting in a significant number of newly documented association (and non-association) records. Twenty published records considered to be erroneous or doubtful are noted, with justifications given for their deletion from the association database. In total, 265 different associations between lycaenids and ants, plus 65 non-attendance records are documented for Australia. Nearly 80% of the lycaenid species in Australia, for which the early stages are known, are recorded associating with ants and half of these are obligately ant-associated. Patterns of association are examined from the perspective of both lycaenids and ants, with a focus on ant systematics and ecology. Lycaenids are recorded with five ant subfamilies, including the first record of an association with the Pseudomyrmecinae. The Dolichoderinae, and to some extent the Formicinae, have a disproportionately high percentage of genera that associate with lycaenid butterflies. All ant species that tend lycaenids spend at least some portion of their time foraging on vegetation to collect plant and insect nectar. There is a robust relationship between the competitive status of ants within a community, and their frequency and degree of association with lycaenids. Obligate ant-association is accompanied by a high degree of specificity for ant partner, but two notable exceptions, Ogyris aenone and O. amaryllis are discussed. Facultative myrmecophiles tend to associate with a broad range of ants, although interactions with ecologically dominant ants are less frequent than might be expected based on the abundance of dominant ant species in Australian communities. |