Ants (Hymenoptera: Formicidae) of Christmas Island (Indian Ocean): identification and distribution

WA Museum Records and Supplements | Updated 7 years ago

ABSTRACT – The composition of the Christmas Island (Indian Ocean) ant fauna is reviewed, leading to the recognition of 52 species in 24 genera and 7 subfamilies. This account amalgamates previously published records and recent extensive surveys of Christmas Island's ant fauna. Eight species represent new records for Christmas Island: Technomyrmex vitiensis, Camponotus sp. (novaehollandiae group), Cardiocondyla kagutsuchi, Monomorium orientale, M. cf. subcoecum, Tetramorium cf. simillimum, T. smithi and T. walshi. Although some of these new species records represent recent taxonomic advances rather than new introductions, we consider four species to be true new records to Christmas Island. These include Camponotus sp. (novaehollandiae group), M. orientale, T. smithi and T. walshi. None of the 52 species reported here are considered endemic. In general, the Christmas Island ant fauna is composed of species that are regarded as worldwide tramps, or that are widespread in the Indo-Australian region. However, Christmas Island may fall within the native range of some of these species. We provide a key to the ant species of Christmas Island (based on the worker caste), supplemented by comprehensive distribution maps of these ants on Christmas Island and a short synopsis of each species in relation to their ecology and world-wide distribution. Because of the large number of world-wide tramp ants on Christmas Island, this key may also prove applicable for introduced species resident on other oceanic islands.