Corythucha morrilli (Osborne & Drake) sucks vascular fluids from leaves of Ipomoea batatas (L.) and causes severe browning and defoliation. Under greenhouse conditions the entire life cycle from egg through five aggregated instars is completed on the plant in nineteen days. Female longevity is about thirty-five days, during which time about 400 eggs are laid. Twenty-one varieties of I. batatas screened against the pest have shown different levels of susceptibility.