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The Essex Naturalist
until later. Some Myrmica workers thought to be M. specioides were collected at
Colne Point in 1990. Geoff Allen and then John Felton confirmed the identity
of this species, which has since been found to occur at ten coastal localities in
Essex, stretching from Broom Hill (West Tilbury) in South Essex to Dovercourt
in North Essex. Specimens from most of these localities have been confirmed by
the late John Felton. It seems very likely that this ant has previously remained
undetected in the county, but the possibility that the species is expanding its
range cannot be dismissed.
The ant has always occurred in thermophilic situations, on sparsely vegetated
sand dune (at Shoebury Old Ranges, Colne Point, Crabknowe Spit (Little
Oakley) and Dovercourt), on a section of unimproved south-facing sea wall at
The Cliff (Burnham-on-Crouch), a sparsely vegetated south-facing landslip
grassland at Bushy Hill (South Woodham Ferrers), old grazing marsh grassland
with sparsely vegetated hummocks and anthills at Fobbing Marshes and Kersey
Marsh (Benfleet Downs) and sparsely vegetated grassland on south-facing
terrace gravels at Broom Hill and Hall Hill (West Tilbury).
Formicoxenus nitidulus (Nylander)
This ant occurs only in the nests of Formica rufa and allied mound building
species (Collingwood 1979). Donisthorpe (1927) gives Hockley as the only
locality in Essex and this is shown in Barrett (1979). We have no recent records
but it is possible that it still occurs in some of our wood ant colonies.
Genus: Leptothorax. Three of the four British species are recorded for Essex.
Leptothorax acervorum (Fabricius)
We have records from ten widely distributed localities in South Essex and Sandy
Wood (Terling) in North Essex. It is rarely found in any numbers.