Malaise and Yellow Pan Traps for Sampling Hymenopteran Parasitoids in Brazil: Abundance, Family Composition, Habitat Variation, and Methodological Complementarity

Malaise and yellow pan/Moericke traps are widely used passive methods for sampling parasitoid Hymenoptera, but differences in trap mechanism, habitat, sampling effort, and taxonomic scope can complicate direct comparisons. This study integrated experimental and faunistic datasets from eight compilations conducted mainly in Goiás and Minas Gerais, Brazil. Only records obtained with verified Malaise traps or true yellow pan/Moericke traps were retained. Clear duplicates and taxonomic subsets were controlled, family-level data were standardized when possible, and chi-square analyses were applied only to suitable categorical counts. In the two largest confirmed multi-family surveys, Malaise traps yielded 6,341 versus 3,406 individuals and 4,135 versus 2,242 individuals in yellow pans, respectively, with significant differences in total catch (p < 0.0001). However, a direct 56-individual Cynipoidea comparison showed no significant difference in total abundance between methods (21 versus 35; p = 0.061), while taxonomic composition differed strongly. Habitat comparisons using yellow pans also showed that similar total abundance could conceal marked compositional turnover: in one 183-individual dataset, forest and pasture totals did not differ significantly, whereas family composition did (p < 0.0001). A 793-individual dataset showed significant differences in both abundance and family composition between habitats. Temporal heterogeneity was also evident in several Malaise and yellow-pan series. Because historical studies differed in trap number, sampling duration, locality, year, and reporting detail, the results were interpreted as method-specific yields rather than universal estimates of trap efficiency. Overall, Malaise and yellow pan/Moericke traps provided selective but complementary representations of parasitoid assemblages, supporting their combined use in inventories and monitoring when abundance, richness, composition, effort, habitat, and sampling period are analyzed separately.