Heterolaccus grandisBurks parasitizes the 3rd instar ofAnthonomus grandisBoheman in parts of Costa Rica, Nicaragua, Guatemala, and Mexico. It has been described as a primary parasite of this pest. In the laboratory, the developmental period was 15–17 days for males and 17–18 days for females at 24–27°C and 45±2%RH. The incubation period for the egg was 27–29 hours. The larvae, which were cannibalistic, have 3 stadia and a larval period of 4.5–5.5 days. The pupal stage was 6–7 days for males and 8 days for females. Oviposition began 3–4 days after adult eclosion. Females deposited an average 6.38 eggs per day, an average total of 315 eggs per female. Average longevity was 51.2 days for males and 65.0 days for females. The culture ofH. grandisfrom Mexico gave no evidence of overwintering. After initial release in the field, percentages of parasitism of boll weevils byH. grandisincreased progressively during the season.