AGGREGATING BEHAVIOR OF <i>UMBONIA CRASSICORNIS</i> (HOMOPTERA: MEMBRACIDAE)

Abstract Individuals of Umbonia crassicornis Amyot and Serville (Homoptera: Membracidae) form aggregations both as nymphs and adults. Each adult female deposits one set of eggs and remains with them. Prior to egg hatching the female moves off the egg mass and makes a series of spiral bark slits with the ovipositor. First instar nymphs aggregate along these slits with the female positioned below the cluster. Adult females use the front tarsi to stroke the backs of moving nymphs to return them to the aggregation. Adult females remain with the nymphs until they become adults. Aggregations of adults fragment when sexually mature; mating takes place before and during dispersal. Mating behavior consists of four components, the precopulatory position being prolonged.