A sexually dimorphic response in supercooling temperature, enhanced by starvation, in the lesser mealworm Alphitobius diaperinus (Coleoptera: Tenebrionidae)

The effect of starvation on supercooling temperature (SCP) distribution was investigated in adults and larvae of Alphitobius diaperinus (Coleoptera: Tenebrionidae).

The mean values for SCPs of adults fed at 20°C were −14.5±2.4°C (31 males) and −10.3±1.3°C (29 females). The distribution of the SCPs of these control adults was unimodal. No significant differences were observed in either mean wet weight or mean dry weight between males and females.

The mean values for SCPs of adults starved for 1 month at 20°C were found to be bimodal due to sexual dimorphism. The mean SCPs for males was lower (−17±2.6°C; 28) than that for females (−11.2±1.8°C; 26). No significant differences were observed in either mean dry weight or wet weight between males and females.

The SCPs of both fed and starved larvae, kept for 1 month at 20°C were −12.3±2.4°C (fed) and −18.0±2.6°C (starved).