An insecticidal compound of formula (I) in which G1, G2, and G3 together with the two carbon atoms to which G1 and G3 are attached, form a non-aromatic 4- or 5-membered ring system; wherein G1 is sulfur, SO, SO2, oxygen, a direct bond, NRa or CR5aR5b; G2 is sulfur, SO, SO2, oxygen, a direct bond, NRb or CR5cR5d; G3 is sulfur, SO, SO2, oxygen, a direct bond, NRc or CR5eR5f; with the provisos that a) not more than 1 group G can be a direct bond, b) not more than 2 G groups can be oxygen, sulfur, SO or SO2 and c) when 2 G groups are oxygen, SO, SO2 and/or sulfur the two groups are separated by a carbon atom; each of Z1 and Z2, which may be the same or different, represents oxygen or sulfur; D is phenyl or a 5- or 6-membered heteroaromatic ring and R1a, R1b, R5a, R5b, R5c, R5d, R5e, R5f, Ra, Rb Rc, R2, R3 and R20 are specified organic groups and agronomically acceptable salts/isomers/enantiomers/tautomers/N-oxides of those compounds.