Who are the superhosts of gall-inducing insects? The need for a conceptual definition

Abstract

The term “superhost” in the context of gall-inducing insects on host plant species has been utilized in various ways, leading to ambiguity and imprecision in its definition. Although most host plant species usually accommodate one or two gall-inducing insect species or morphotypes, the term’s interpretation varies widely in the literature, with “superhost” designations ranging from plants hosting 20 gall-inducing species to just two species. Therefore, based on Neotropical data compiled we suggest classifying a host plant species as “superhost” only when it exhibits a high local richness of gall-inducing insect species, which we define as six or more species of gall-inducing insects. This proposition aims to use the term “superhost” only in cases of plant species with high local richness of gall-inducing insects, establishing a framework for consistent terminology. To enable fair comparisons in insect-plant interactions, a cautious and standardized use of the term “superhost” across various geographical scales is essential.