Data from: Insights into the population genetics of an extreme habitat specialist, the wood ant commensal Formicoxenus nitidulus

Habitat specialists, particularly those that are poor dispersers, are
highly susceptible to population isolation as a result of habitat
fragmentation. Population isolation can lead to inbreeding, resulting in
reduced genetic diversity and an increased risk of local
extinction. The shining guest ant, Formicoxenus
nitidulus, lives only within the nests of its wood ant hosts. It is thus
an extreme habitat specialist, dependent on patchy nesting sites within an
already fragmented woodland habitat. We aimed to generate the first data
on the population genetics of this species, to characterize its genetic
diversity and degree of population isolation. We developed eight
novel nuclear microsatellite markers and generated mitochondrial DNA
sequence data of the COI region to characterize samples from seven
UK F. nitidulus populations collected from nests of three wood
ant hosts: Formica aquilonia, Formica lugubris, and Formica rufa. These
novel nuclear microsatellite markers can be used in future studies of this
species across a wider geographic range and may have utility in other
closely related species. We found clear differentiation between
Scottish and English F. nitidulus populations. The six largest
study populations were genetically diverse, showing signs of effective
within-site dispersal. Our data show that wood ant nests often host
multiple F. nitidulus colonies. We found that genetic diversity
has been maintained in this extreme habitat specialist at risk of
population isolation. We also demonstrate that a single wood ant host nest
can have high conservation importance for the multiple F.
nitidulus colonies it supports.