Community ecology of the ‘other’ parasitoids

• Many diverse lineages of parasitoids exist in addition to parasitic wasps.
• The community ecology of these ‘NH-parasitoids’ is poorly known.
• NH-parasitoid assemblages vary with host traits, habitats, and landscape structure.
• They often differ from parasitic wasps in host specificity and food-web structure.
• Recent technical and conceptual advances hold great promise for further research.

The study of parasitoid communities is an active and dynamic field. Most studies, however, are focused primarily on parasitic wasps, despite the thousands of other insect parasitoids distributed across many lineages. Although questions in parasitoid community ecology are much the same for different groups, answers to these questions may not be due to differing biological traits. The ecology of non-hymenopteran (‘NH’) parasitoid communities is poorly known, but recent work indicates that habitat and host traits have strong impacts on the size and composition of these parasitoid assemblages. Recent food-web analyses indicate that host ranges vary widely within and among taxa and associations are shaped by host ecology and defenses. Evidence is also accumulating for strong ‘bottom-up’ and ‘top-down’ multi-trophic interactions between NH-parasitoids and nonadjacent trophic levels, as well as trait-mediated indirect effects on communities. Recent technical and conceptual advances in characterizing and comparing food webs, consideration of phylogenetic history, and increasing anthropogenic impacts provide many new and stimulating areas of research on parasitoid communities.