Introduction of the larval parasite Bathyplectes curculionis (Thomson) into the Yuma Valley was one of the first counter measures taken against the Egyptian alfalfa weevil (Hypera brunneipennis (Boheman)) following its discovery in the U.S.A. The colonization material was obtained from Utah's Salt Lake Valley where the parasite had been successfully introduced from Southern Europe against the alfalfa weevil (Hypera postica (Gyllenhal)) early in this century.