摘要:The hypothesis of higrothermal stress predicts a gradient of diversity in the direction Cerrado ? forest, showing a higher preference of galling insects for xeric environments. However, some studies have pointed out that other factors are more important at local scales, such as seasonality. Thus, the objectives of this study were: test the hypothesis of higrothermal stress and investigate whether there are effects of seasonality in the patterns of distribution of galling insects. The study was carried out from September 2007 to June 2008 at the Parque Estadual da Serra dos Pireneus, in Pirenópolis, Goiás. During this period, samples of galls were collected within a fragment of xeric (Cerrado sensu stricto) and mesic (semideciduous forest) vegetation through transects sampled for 1 h and 30 min. The gall morphotypes collected were sent to the laboratory of Entomology of the Universidade Federal de Goiás to detect the galling insects. No significant differences were observed between the average richness of galls in the Cerrado and forest. On the other hand, the richness of galls was statistically different comparing the numbers of morphotypes in the dry and rainy seasons. The results of this study indicate that seasonal patterns can play a more decisive role in the diversity of galling insects than the phytophysiognomic type.