FMRfamide-like immunoreactivity in the ventral nerve cord of the larval eastern spruce budworm,Choristoneura fumiferana (clemens) (Lepidoptera : Tortricidae)

Distribution of FMRFamide-like immunoreactivity was examined in the larval ventral nerve cord of the eastern spruce budworm, Choristoneura fumiferana (Lepidoptera : Tortricidae). Indirect immunofluorescent methods revealed the existence of 3 groups of FLI neurons in each ganglion. The neurons are distributed in a bilaterally symmetrical fashion at the anterodorsal, midlateral and posteroventral regions of the ganglia. There are 4 FMRFamide-like immunoreactive fiber tracts on the dorsal surface of the ganglia to which the anterodorsal FLI neurons project ipsilaterally, while the midlateral pair projects both ipsi-, and contralaterally. The last abdominal ganglion (AG8) has 4 additional pairs of FLI neurons; and axons from some of these extend into the median abdominal nerve, which suggests some role for this neuropeptide in the control of posterior structures of the larva.