Fall armyworm (Lepidoptera: Noctuidae) parasitoids: differential spring distribution and incidence on corn and sorghum in the southern United States and northeastern Mexico

Nineteen species of parasitoids were recovered from fall armyworm, Spodoptera frugiperda (J.E. Smith), in spring surveys conducted in Florida, Georgia, Alabama, South Carolina, Louisiana, Mississippi, south Texas, and Mexico during 1981-1983. The highest rates of parasitism were in overwintering areas of Mexico-Texas and south Florida, averaging 23.4 and 32.5%, respectively. Chelonus insularis Cresson was the most common species and represented 61.7, 59.6, and 56.1% of the parasitoids recovered from small, medium, and large larvae, respectively. Evidence of differential distribution of some species was indicated by their native scarcity or abundance in defined geographical areas within the temporal limits of the study. For example, Temelucha difficilis Dasch was an important species in south Florida but it was rarely observed in more northerly areas. Conversely, C. sonoronsis was absent in collections from south Florida but was an important species elsewhere.