In Florida, Fall armyworm, Spodoptera frugiperda (J. E. Smith) is often called armyworm, and occurs Figure 1. Adult armyworm, Mythimna unipuncta ( Haworth).
Larvae: There usually are six instars in fall armyworm. Head capsule widths are about 0.35, 0.45, 0.75, 1.3, 2.0, and 2.6 mm, respectively, for instars 1-6. Larvae.
Adults. Once emerged, the adults live for about 10 days, and sometimes up to 21 days, with the female laying most of her eggs early.
Larva, Spodoptera frugiperda (fall armyworm); larva on maize cob. The larvae, which are marked with a distinct inverted "Y" on the front of the.