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Cynipidae (Hymenoptera: Cynipoidea) is a diverse group of wasps, many of which are capable of inducing plants to make galls, novel structures that protect and nourish the wasps' larvae. Other cynipids, especially those species in Ceroptresini and Synergini, are understood to be usurpers of galls made by other cynipids. The North American cynipid fauna has not been fully catalogued since 1979, but there is renewed interest in revising the taxonomy and in doing research that sheds light on the mechanisms of gall induction, the evolution of this life history, and their ecological interactions more broadly. Significant taxonomic changes have impacted the group since 1979, thereby warranting a new catalogue. The current state of knowledge of species classified in Aulacideini, Ceroptresini, Diastrophini, Diplolepidini, Phanacidini and Synergini in the United States, Canada, and Mexico is summarised in catalogue format. We report 323 names, including 170 valid species of rose gall wasps, herb gall wasps, and inquiline gall wasps, classified in 12 genera, from the United States, Canada, and Mexico. Current taxonomic status, distribution, host associations, and vernacular names are listed for each species. The catalogue also includes the original description of galls for many species of gall-inducer, as well as atomised characterisations of different gall traits as key-value pairs. For most galling species without existing vernacular names, new vernacular names are proposed.
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Comprehensive phylogenomic analyses re-write the evolution of parasitism within cynipoid wasps
Abstract Background Parasitoidism, a specialized life strategy in which a parasite eventually kills its host, is frequently found within the insect order Hymenoptera (wasps, ants and bees). A parasitoid lifestyle is one of two dominant life strategies within the hymenopteran superfamily Cynipoidea, with the other being an unusual plant-feeding behavior known as galling. Less commonly, cynipoid wasps exhibit inquilinism, a strategy where some species have adapted to usurp other species’ galls instead of inducing their own. Using a phylogenomic data set of ultraconserved elements from nearly all lineages of Cynipoidea, we here generate a robust phylogenetic framework and timescale to understand cynipoid systematics and the evolution of these life histories. Results Our reconstructed evolutionary history for Cynipoidea differs considerably from previous hypotheses. Rooting our analyses with non-cynipoid outgroups, the Paraulacini, a group of inquilines, emerged as sister-group to the rest of Cynipoidea, rendering the gall wasp family Cynipidae paraphyletic. The families Ibaliidae and Liopteridae, long considered archaic and early-branching parasitoid lineages, were found nested well within the Cynipoidea as sister-group to the parasitoid Figitidae. Cynipoidea originated in the early Jurassic around 190 Ma. Either inquilinism or parasitoidism is suggested as the ancestral and dominant strategy throughout the early evolution of cynipoids, depending on whether a simple (three states: parasitoidism, inquilinism and galling) or more complex (seven states: parasitoidism, inquilinism and galling split by host use) model is employed. Conclusions Our study has significant impact on understanding cynipoid evolution and highlights the importance of adequate outgroup sampling. We discuss the evolutionary timescale of the superfamily in relation to their insect hosts and host plants, and outline how phytophagous galling behavior may have evolved from entomophagous, parasitoid cynipoids. Our study has established the framework for further physiological and comparative genomic work between gall-making, inquiline and parasitoid lineages, which could also have significant implications for the evolution of diverse life histories in other Hymenoptera.
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- PAR ID:
- 10218754
- Date Published:
- Journal Name:
- BMC Evolutionary Biology
- Volume:
- 20
- Issue:
- 1
- ISSN:
- 1471-2148
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1186/s12862-020-01716-2
