|Publication Type:||Journal Article|
|Year of Publication:||2014|
|Authors:||E. M. Sarnat, Rabeling, C., Economo, E. P., Wilson, E. O.|
|Pagination:||301 - 307|
|Keywords:||biological invasion, Invasive ants, Melanesia, Pacific islands, Pheidole, Tramp ants, Vanuatu|
Ants are among the world’s most destructive invaders, and Pacific Islands are particularly susceptible to invasion by non-native ant species.
A species from the taxonomically problematic Pheidole flavens-complex is reported here for the first time from the southwestern Pacific.
Specimens of the species reported here were collected November 2011 from an established colony on Espiritu Santo, Vanuatu, during a
survey of the island’s ant fauna. Morphological and genetic analyses revealed these Vanuatu specimens belong to the Neotropical P. flavens
group. The DNA sequence data most closely matched those of two specimens previously determined as P. moerens Wheeler and P. flavens
Roger. A closely related taxon currently being treated as P. moerens Wheeler was reported from Hawaii in 2005. Preliminary morphological
analysis suggests that the Vanuatu population reported here represents a different species than the Hawaii P. moerens. However, a valid
species name cannot be confidently applied to either the Hawaii population or the Vanuatu population until a comprehensive taxonomic
revision of the flavens-complex is completed. Species of the Pheidole flavens-complex are occasionally considered pest ants, but have not
been documented as causing significant harm to native species, food security or public health. However, the recent spread of species in this
complex across the southeastern United States, recent introductions to California and Hawaii, and the recent discovery in Vanuatu suggests
their potential for human-mediated dispersal and establishment. We hope that raising awareness of this new incursion will improve the
chances of early detection and eradication before the species spreads further into the Pacific Island region. We provide specimen photographs
of the major and minor caste and a brief diagnosis that can be used to separate this species from other Pheidole species introduced in the
Pacific island region, including Pheidole megacephala (Fabricius) and the morphologically similar Pheidole parva.