Metabolic rates of pitbuilding and non-pitbuilding antlion larvae (Neuroptera: Myrmeleontidae) from southern Africa

Hourly metabolic rates, measured as oxygen consumption, were relatively high from 1000 to 2100h compared with 2200 to 0500h forCuetasp., whereasFurgella intermediaexhibited a peak in the afternoon, from 1300 to 1700h. The resting metabolic rates ofCuetasp.,F. intermediaandPalpares annulatuswere between 5•4–8•9% of the expected values for similar-sized poikilothermic invertebrates. These values indicate low energy demands, which is crucial to survive prolonged periods of starvation. The non-pitbuilding antlion larva,F. intermedia, was generally more active thanCuetasp., with an unexpectedly high specific metabolic rate for its body size.Furgella intermediahad lower Q10values between 10–30°C than the pitbuilderCuetasp., implying a larger metabolic tolerance to these temperatures. The increase in metabolism after feeding (ranging between 2•8–3•7 times pre-feeding metabolism) was lowest for the largerP. annulatus, indicating low feeding costs for this species.