It has now been found that certain tricyclic derivatives have provided unexpected insecticidal activity. These compounds are represented by formula I: wherein R
1
through R
8
, inclusively, and X and Y are fully described. Compositions comprising an insecticidally effective amount of at least one compound of formula I, and optionally, an effective amount of at least one of a second compound, with at least one insecticidally compatible carrier are also disclosed; along with methods of controlling insects comprising applying said compositions to the locus where insects are present or are expected to be present.