SELECTIVE FORAGING BEHAVIOR IN NEST-PROVISIONING FEMALES OF PARASTRACHIA-JAPONENSIS (HEMIPTERA, CYDNIDAE) - CUES FOR PREFERRED FOOD

Females of Parastrachia japonensis (Hemiptera: Cydnidae) provision nym ph-containing nests with drupes of the single host tree, Schoepfia jas minodora (Rosidae: Santales). P. japonensis feeds on the endosperm of these drupes. Foraging females approached and accepted only a few sele cted drupes for transport to their nests from among the hundreds of dr upes scattered on the ground. The characteristics of the drupes that e licited an acceptance response under field conditions were examined Fe males estimated the degree of endosperm development using volatile and nonvolatile chemicals in the outer skin as cues and selected only tho se drupes which had a well-developed endosperm. Although the cues that prompted approach and inspection of a drupe are in the fleshy outer s kin, females presented with various substitute drupes coated with oute r skin juices of acceptable drupes selected only those they could reco gnize as a solid mass, suggesting that they used volatile chemicals in the outer skin as cues for approaching and inspecting a drupe and the n taste and tactile stimuli as cues for acceptance, Thus, this bug pos sesses a complex, ecologically sensitive cognitive system that enables it to recognize valuable food items by using reliable cues. The impor tance of selective foraging by P. japonensis females and the evolution ary significance of this behavior are discussed.