In Missouri
This is the least common of the dulotic (technical term for slavemaker) Formica species in Missouri. It is a small, slender, brown species which is only faintly bicolored, in contrast to the larger, evidently red and black, more common species.
Formica creightoni nests are very similar to those of the host species, the workers of which, in the mixed population of Formica creightoni colonies, do all construction work. Nests are most often encountered under small-diameter (5-15cm diameter) rotting logs on the woodland floor, or in small rotten stumps. Often, small mounds of excavated soil and leaf fragments are piled around the nest entrance. So far, Formica creightoni has been encountered in Missouri only in open white oak/black oak woodlands in two northeastern region state parks. In both locations these woodlands are under active management, including selective thinning and periodic prescribed burning to encourage groundlayer vegetation density and diversity.
The host species of Formica creightoni in Iowa, where it was first described, is Formica neogagates, but this species does not occur at either Missouri site. Here the host species is the common, northern, brown color form of Formica pallidefulva (long known as Formica nitidiventris). The two species are so similar in superficial appearance that it requires a close look to appreciate that about 3/4 of the workers in a Formica creightoni colony are those of the host species. Formica creightoni carries out raids on Formica pallidefulva nests to pillage their pupae on hot, dry afternoons in late June through August. The
relatively small and slender winged females and males of this species occur in the nest in mid summer. Flight activities and colony foundation have not been observed.
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