Morphological caste differences in the neotropical swarm-founding polistine wasps:: Parachartergus smithii (Hymenoptera: Vespidae)

As part of a series of papers aimed at studying caste in epiponine wasps, this paper deals with Parachartergus smithii. The whole female population of a mature nest (131 workers, 14 intermediates and 5 queens) was measured and dissected. Canonical discriminant analyses indicated slight morphological caste differentiation. Mahalanobis distances for queen-worker, queen-intermediate and intermediate-worker were 10.33, 10.86 and 0.90, respectively. However, ovaries were much more developed in queens than in workers and intermediates indicating clear physiological differences. In addition, castes were distinguished by color patterns in the frons, clypeus, mandibles, gena and wings. An brief comparison of caste differences in the Epiponini reveals both allometric and non-allometric patterns.