Tri-trophic networks of plants, gall-inducers, and micro-hymenopterans in tropical forests of the Peruvian Amazon

Abstract

Interactions between host plants, insect herbivores, and parasitoids are fundamental to understanding ecosystem dynamics. In the present study, we describe the network structure of assemblages composed of host plants, galling insects, and micro-hymenopterans in four vegetation types in two protected areas in the Peruvian Amazon. In total, we recorded 13 host plant species, 20 species of galling insects and 31 taxa of micro-hymenopterans. The network of host plants and galling insects in the white sand-wet forest was very specialized, characterized by low connectance, low linkage density and higher modularity than expected based on the null model, compared to other vegetation types. The galling-micro-hymenopteran interactions in the terra firme and white-sand wet forest were characterized by lower connectance, lower linkage density and higher modularity than expected based on the null model. Our findings show that the high specialization in the plant-gall insect and gall insect-micro-hymenopteran networks reported in other biomes is also found in the Peruvian Amazon.