F. exsecta is placed in the Coptoformica subgenus within the genus and is closely related to Formica exsectoides, an American species.

The largest known polydomous system of F. exsecta consists of 3,350 nests dispersed over about 22 ha in Transylvania, Romania.

[1][2] In Great Britain, F. exsecta can be found only in a few scattered heathland locations in South West England — principally Chudleigh Knighton Heath and nearby Bovey Heath, which are both managed by the Devon Wildlife Trust, and in the central Scottish Highlands (including Rannoch Moor).

[3] A population centre previously existed in the New Forest, and such eminent myrmecologists as Horace Donisthorpe recorded this species there and in Parkhurst Forest on the Isle of Wight in the last century, but this seems to have declined considerably over the past few decades, and recent searches in such locations have failed to find any trace of colonies.

The narrow-headed ant is currently one of the target species in the Back from the Brink project, which aims to extend its range in England.

For a polygynous colony to thrive, it must adjust its sex allocation practices contingent on the abundance of resources.

Procreation between related individuals of the colony can be further explained by the queen-male relatedness coefficient of 0.23, found by experiments from Liselotte Sundström.

An unusual 0.75 relatedness coefficient between full haplodiploid sisters is one of the main contributors to the frequency of evolution of eusocial species.