Wood Ants (Formica rufa)
Actual size 10mm, Silverdale, Lancashire, UK

Canon EOS 300D and 100mm f2.8 macro, f/9, 1/200 with fill in flash

Wood ants build huge nests in Silverdale wood in Lancashire. Approach with caution as they are very aggressive, spraying up to a metre away with formic acid. I could only photograph for a minute before being retiring; covered in ants.