POSSIBLE DUAL COLD-HARDINESS STRATEGIES IN CISSEPS FULVICOLLIS (LEPIDOPTERA: ARCTIIDAE)

Abstract
Insects are usually classified as either freeze-intolerant or freeze-tolerant (Danks 1978; Sømme 1982; Baust and Rojas 1985). Freeze-intolerant species cannot survive the formation of ice in their bodies and typically lower their supercooling points (SCP), the temperature of spontaneous ice formation, during the winter months (Sømme 1982). This is the lower lethal temperature for the insect, although prolonged exposure to temperatures above this may be harmful (Turnock et al. 1983). On the other hand, freeze-tolerant insects can survive the presence of ice crystals in their extracellular fluid and usually have nucleators that prevent supercooling below – 10°C (Zachariassen 1982).