Water Relations of Immature and Adult Lesser Cornstalk Borers, Elasmopalpus lignosellus (Lepidoptera: Pyralidae)

Water content, cuticular permeability, and percentage of total body water (% TBW) lost as a function of time was determined with larval, pupal, and adult lesser cornstalk borers (LCB), Elasmopalpus lignosellus (Zeller). No relationship was detectable between initial weight and % TBW or cuticular permeability for any of the stages, although both parameters varied among stages. Larvae had the greatest % TBW (77.1 ± 2.0%) ($$\bar x$$ ± SE) and the greatest cuticular permeability (12.1 ± 1.2 μcm⁻²Â·h⁻¹Â·mm Hg⁻¹), whereas adult females had the least % TBW (63.2 ± 1.2%) and pupae the least cuticular permeability (1.1 ± 0.3 μcm⁻²h⁻¹mmHg⁻¹). Mean % TBW lost increased linearly with time for each stage. Larvae, pupae, adult females, and adult males lost 30.6 ± 4.9, 6.0 ± 0.6, 28.7 ± 0.5, and 43.1 ± 1.5% TBW, respectively, at 24 h. All stages of the LCB, particularly the pupae, are much more xeric-adapted than many other arthropods.