ARTS: Broadening capacity for research on gall wasps in North America

Gall wasps (Hymenoptera: Cynipidae) are a diverse group of insects, many of which cause the formation of novel structures on plants, called galls. These elaborate and unusual growths provide shelter and food for developing wasp larvae. Cynipid wasps induce galls on many types of plants, and recent research has demonstrated their utility in understanding insect evolution, coevolution, community ecology, and plant physiology. However, systematics research on gall wasps, especially the process of naming, classifying, and estimating evolutionary history (phylogenetics), processes that help bring these species into the broader scientific realm, has lagged behind that of other insect groups. This predicament is especially true of those gall wasp species native to North America. This project will, in part, yield resources that facilitate research on these wasps, mainly monographs (compilations of all known species with descriptions and distribution data), phylogenies (reconstructions of evolutionary history), and diagnostic tools, for at least two tribes: Aulacideini and Diastrophini. These wasps are common, and they induce galls on many recognizable plants, including wild lettuces, rosinweeds, brambles, and cinquefoils. These two tribes are among the least studied of all gall wasps, and only a small handful of studies have ever been published on these groups. Species belonging to these groups also show potential for use as models for evolution or speciation, but their relevance is obfuscated by incomplete taxonomic knowledge. The project will also produce materials that can be used in educating graduate and undergraduate students and the public more broadly about systematics and gall biology. The research team will revise the North American fauna of the gall wasp tribes Aulacideini and Diastrophini using an integrated taxonomic framework comprising morphology, biological and ecological data, DNA barcoding data, and characters related to galls, which act as extended phenotypes of the gall inducer. Robust classification above the species level will be underpinned by analyses of ultraconserved elements (UCEs). These data will lend themselves to testing myriad species concepts, especially with regard to the UCE dataset, and should yield robust, time-calibrated phylogenies. The revisions will enable and inform the applicability of these insects to other research domains. For example, Diastrophus species on Rubus plants and Antistrophus species on Silphium plants will be explored for their potential as a model systems to understand how insects are able to manipulate plants. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.