Synhospitality of eriophyoid mites (Acariformes, Eriophyoidea): taxonomic analysis of gall-forming mite species complexes on boreal woody dicotyledons

Microscopic mites of the Eriophyoidea superfamily are characterized by an ability to cause the growth of galls on plants. Synhospital complexes of gall-forming Eriophyoidea (SCGE) species are formed by several species of gall mites coexisting on the same host plant. To assess the phenomenon of synhospitality, we investigated the features of the taxonomic composition and diversity of galls formed by eriophyoid mites on boreal woody dicotyledons and carried out a statistical analysis of the host relationships of different gall mite genera from the Eriophyidae family. We found out that phylogenetically closely related hosts within biogeographically integral territories possess the similar SCGE. During colonization of plants, gall mites demonstrate a high ability to cryptic speciation, which leads to genesis of morphologically similar mite species that cause the formation of different types of galls. Host preferences of gall mites belonging to the different supergenera groups play an important role in the formation of the SCGE, which determines the differences in mite taxa spectra associated with hosts from different families. In general, the results of the work demonstrate that the synhospitality of Eriophyoidea is not a random process, but is the result of a long-term coadaptation in the “parasite–host” system. This is one of the phenomena reflecting the stages of the global historical process of the colonization of Embriophyta plants by mites of the Eriophyoidea superfamily.