MORPHOLOGICAL CASTE DIFFERENCES IN AGELAIA-VICINA, THE NEOTROPICAL SWARM-FOUNDING POLISTINE WASP WITH THE LARGEST COLONY SIZE AMONG SOCIAL WASPS (HYMENOPTERA, VESPIDAE)

Clear differences in external and internal morphology were detected be tween queens and workers of Agelaia vicina which probably attains the largest colony size among the Polistinae. Morphometric comparisons for 27 external characters show that queens have smaller heads, larger me sosoma, and larger metasoma than workers. The metasoma of queens are m uch more developed than that of workers to accomodate developed ovarie s. Queen's gastral tergite I is much more robust as compared to worker 's, apparently in order to support the enlarged metasoma. The colorati on does not essentially differ between castes. Multiplication of ovari oles is not seen in queens, but each ovariole is long and folded. Neve rtheless, the morphological caste differentiation in A. vicina is lowe r than in some congeners with smaller colonies, e.g., A. flavipennis a nd A. areata.