Tapinoma melanocephalum (Fabricius, 1793)

Ivanov, Kaloyan, 2016, Exotic ants (Hymenoptera, Formicidae) of Ohio, Journal of Hymenoptera Research 51, pp. 203-226 : 206-209

Tapinoma melanocephalum (Fabricius, 1793)

Distribution in Ohio.

Widespread in Ohio. Counties: Butler (material examined: Oxford, Miami University, Belk Greenhouse, 25.ii.2014, leg. S. Mays), Cuyahoga (material examined: Cleveland, 07.ii.2008, leg. K. Ivanov, and 04.iii.2008, leg. B. Poynter, same locality, in an animal care zoo facility), and Franklin (photographs examined: Columbus 25-29.ii.2008, photos by S. Heideman, in a conservatory), (Fig. 1 ).

Where found/Habitat.

Indoors, abundant in greenhouses, conservatories and zoo buildings.

Origin.

Indo-Pacific.

Natural history.

This widely distributed tramp species is more prevalent in disturbed areas but also has been encountered in natural habitats in its introduced range ( Wetterer 2009 and references therein). Unlike many other exotic ants, this species can be distinguished easily by its minute size, peculiar coloration (Fig. 2 ), and the rapid, erratic movements when disturbed.

Colonies are moderate to large in size, and polygynous, with queens distributed in multiple nests. Additional features characteristic of this ant include unicoloniality, intranidal mating, and colony formation via budding ( Bustos and Cherix 1998). Ghost ants are opportunistic nesters, usually in disturbed areas, and frequently relocate their nests ( Wetterer 2009). Inside buildings, nests can be found in flowerpots, in small cracks and crevices, beneath baseboards, and in wall spaces ( Klotz et al. 2008).

Where it occurs this ant is a major nuisance pest, both indoors and outdoors, that tends mealybugs and scale insects and scavenges for dead insects and food scraps ( Smith 1965). The ghost ant is confined to greenhouses and other heated buildings in northerly states, which provide the high temperature and environmental humidity needed for the survival of this tropical species. According to Wetterer (2009), at latitudes greater than 30° this species is largely restricted to living inside buildings.

I have only seen this species at a single animal care facility in the greater Cleveland area where I observed multiple nests in wall spaces and crevices. In addition, numerous foragers were noted near and at reptile feeding stations. In Ohio, this ant is a known conservatory and zoo pest, likely distributed via potted plants or animal feed. Unpublished observations suggest that this ant has been present in the state since at least the early 2000s (B. Poynter and M. Vincent pers. communication).

Figures

Figure 1. Distribution of Linepithema humile (1), Tapinoma melanocephalum (2), Nylanderia flavipes (3), and Paratrechina longicornis (4) in Ohio.

Figure 2. Tapinoma melanocephalum workers from a conservatory in Franklin Co. (Photo: S. Heideman).