CUTANEOUS WATER-LOSS OF SEVERAL STAGES OF THE RED IMPORTED FIRE ANT, SOLENOPSIS-INVICTA (BUREN)

1. Cuticular permeability and % total body water (%TBW) of living, HCN-killed, and hexane-extracted red imported fire ant, Solenopsis invicta (Buren) (Hymenoptera: Formicidae), workers were measured for three size-classes. 2. Initial body mass ranged from 0.48 to 5.21 mg and calculated surface areas ranged from 0.04 to 0.36 cm2, for small and large workers, respectively. 3. Mean %TBW was 61.1 for large workers and 65.0 for small workers. 4. Mean cuticular permeability was not related to initial mass and was 31.96 and 25.23-mu-g/cm2/hr/mmHg for small and large workers, respectively. 5. Death by exposure to cyanide gas increased cuticular permeability ca 1.5-fold. Hexane extraction caused ca 1.8-fold increase in cuticular permeability. 6. These results suggest that epicuticular lipids may be less important in cuticular waterproofing than metabolic processes.