Galls are products of anatomical, metabolic, and chemical alterations in host plant tissues, caused by parasitic organisms named gall inducers. Gall inducers can potentiate chemical and structural specializations of their host plants for their own benefit, such as the accumulation of bioactive and antioxidant secondary metabolites, which should be tested. This could lead to increased protection against natural enemies, pathogens, and different abiotic stressors. Based on data in the literature, we listed the gall morphotypes found in restingas (threatened coastal vegetations) in Rio de Janeiro State, Brazil, and reunited the anatomical, phytochemical, and medicinal information of the host plants. Superhost plants, capable of hosting more than one gall-inducing species, represented 51% of the hosts, with 80% of the listed galls. Phytochemical and pharmacological potentials were confirmed for 80% of the gall superhosts. Most of the non-medicinal superhosts belong to species or families of toxic plants. These facts indicate the high percentage of superhost species capable of producing and accumulating secondary metabolites. Anatomical, phytochemical, and pharmacological potentials of the 17 most widely distributed superhosts are discussed in detail. These plants have metabolites with antimicrobial and antioxidant activity, among several other pharmacological properties. Data gathered here revealed that superhost plants of galling organisms have wide distribution in restingas, accumulate diverse secondary metabolites, and several of them are reported to have bioactive or pharmacological properties. Families of superhost plants not necessarily are those richer and more diverse in restingas, indicating that specific chemical and structural features of host plants are preponderant in galling arthropod-plant interactions. Based on our results, we indicated some superhosts as study models to test the potentiation of such features in galls, which were selected based on the number of associated galls, the types of secondary metabolites detected, and the presence of bioactive substances.
