NOVEL ISOXAZOLINES OF THE FORMULA (I) WHEREIN A REPRESENTS C OR N R REPRESENTS HALOALKYL X REPRESENTS HALOGEN OR HALOALKYL 1 REPRESENTS 0, 1 OR 2 Y REPRESENTS HALOGEN, ALKYL, ALKOXY, HALOALKYL, CYANO, NITRO, AMINO, ACYLAMINO, ALKOXYCARBONYLAMINO, HALOALKOXYCARBONYL-AMINO OR ALKYLSULFONYLAMINO M REPRESENTS 0, 1 OR 2 AND G REPRESENTS ANY ONE SELECTED FROM HETEROCYCLIC GROUPS DESCRIBED IN THE SPECIFICATION AND A USE THEREOF AS INSECTICIDES AND FOR CONTROLLING ANIMAL PARASITES.