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[Vol. 94 
Fig. 2. Variation in the number of eggs per egg mass. 
One or more wasps emerged from 79 of 103 (77%) A. sparsa egg 
masses (26% of all eggs). None of the egg masses, however, was 
completely parasitized — 85% was the highest value obtained. In 
contrast, Carroll (1978) found 86 percent of egg clutches (n = 117, 
31.5 eggs per clutch) of Stolas sp., a Brazilian cassidine that does not 
have maternal guarding, were completely parasitized by wasps; 14 
percent were totally unparasitized. Thus, guarding may make it less 
likely that all eggs in an egg mass are parasitized. 
Eberhard (1975) noted that maternal guarding by the pentatomid, 
Antiteuchus tripterus Ruckes, was highly effective against generalist 
predators and phoretic egg parasitoids. However, when he removed 
mothers from their clutches, the number of eggs parasitized actually 
decreased because parasitoids apparently used olfactory or visual 
cues associated with the mother to locate egg masses. This may also 
occur with A. sparsa and deserves investigation. 
Opportunistic predators of eggs 
The importance of maternal guarding during the egg stage was 
investigated by locating eighteen egg masses with mothers at the 
