Formica cunicularia

Formica cunicularia (Latreille) is a mining ant of the Formica fusca group. Forelian systematics places it in the subgenus Serviformica. Locally common in southern England, its appearance and habits ally it, to some extent, with Formica rufibarbis, although the former's red markings are far less conspicuous. Horace Donisthorpe comments:

Forel points out that [Formica fusca var.] rubescens [=F. cunicularia] has frequently been confounded with rufibarbis, and it is probable that some British records of [...] rufibarbis really refer to this variety.

F. cunicularia, unlike most other Formica fusca-group species, can form noticeable hillocks over its nests, and in addition to these produces rufibarbis-like runs in the vicinity of its nest. Donisthorpe states that:

In the New Forest it occurs in earth-mounds, at Seaton under stones, in the Landslip, Isle of Wight, in the side of the cliff, and at Fairlight I found it in the side of the cliff and in earth-mounds in the undercliff - one of the nests being traced by tracking a worker which was carrying home a fly in its jaws.

Donisthorpe records the species as having occurred as far north as Bewdley in Worcestershire.