Experiments conducted to evaluate the suitability of T. evansi as a source of food for P. persimilis revealed that the primary factor responsible for the low oviposition rate and vurvivorship of the predator when fed T. evansi was the low amount of food ingested. P. persimilis detected and initiated feeding on T. evansi equaly as well as on T. urticae. However, a feeding depressant was apparently responsible for a longer time spent by P. persimilis feeding on eggs of T. evansi than on eggs of T. urticae. Eggs of the former prey were totally consumed only occasionally. The depressant effect influenced subsequent feeding on T. urticae, increasing the time requered for consomption and the number of partially consumed eggs for at least 3 days
