494 Felippotti et al.

Degree of morphological difference between queens and workers is an important characteristic used to infer the mechanism of caste determination and levels of reproductive conflict in insect societies. In the polistine wasps, the degree of morphological caste difference varies widely, ranging from absent to highly distinct. A lack of obvious caste differences would indicate that most females are totipotent (Strassmann et al. 2002, Mateus 2005), which predicts that reproductive conflict will be higher than in species with well-defined caste roles. For Neotropical swarm-founding polistine wasps (tribe: Epiponini), West-Eberhard (1978, 1981) suggested that castes may be post-imaginally determined in some species. Indeed, female reproductives resemble non-reproductives in morphology in a number of species, and this pattern has been found in Parachartergus Ihering, 1904 (Mateus et al. 1997