A Parasitoid/Host Relationship
The caterpillar of the giant leopard moth (Hypercompe scribonia) can fall prey in its cocoon to a fly that drills in and lays eggs. The larvae will consume the caterpillar before they emerge as adults.
The moth is part of the family Erebidae. They are distributed through North America from southern Ontario, and southern and eastern United States through New England, Mexico and down to Panama.