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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Systematic Entomology Laboratory » Research » Publications at this Location » Publication #389159

Research Project: Systematics of Beetles, Flies, Moths and Wasps with an Emphasis on Agricultural Pests, Invasive Species, Biological Control Agents, and Food Security

Location: Systematic Entomology Laboratory

Title: Reinterpreting the diversity and host preference of Sycophila parasitoid wasps associated with oak galls

item ZHANG, MILES - University Of Florida
item SHEIKH, SOFIA - University Of Iowa
item WARD, ANNA - University Of Iowa
item FORBES, A. - University Of Iowa
item Gates, Michael
item EGAN, SCOTT - Rice University
item DAVIS, CHARRLES - Rice University
item WEINERSMITH, KELLY - Rice University
item LUCKY, ANDREA - University Of Florida
item MELIKA, GEORGE - University Of Budapest

Submitted to: Molecular Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/23/2022
Publication Date: 6/28/2022
Citation: Zhang, M.Y., Sheikh, S., Ward, A., Forbes, A.A., Gates, M.W., Egan, S., Davis, C., Weinersmith, K., Lucky, A., Melika, G. 2022. Reinterpreting the diversity and host preference of Sycophila parasitoid wasps associated with oak galls. Molecular Ecology. 31:4417-4433.

Interpretive Summary: Insects that induce tumor-like growths on plants (galls) cause significant economic damage to horticultural and agricultural commodities (ornamental and food/fiber plants). Parasitic wasps are known to attack these gall-forming insects and provide biological control of such pests. Here we report on parasitic wasps associated with oaks in North America. This information will be useful to ecologists, foresters, entomologists, and horticulturalists.

Technical Abstract: The oak gall wasp and their associated parasitoids represent an extremely species-rich but understudied system that can be used to address macroevolutionary and ecological questions. The diversity of gall wasps and their associated gall morphology are thought to have evolved as a countermeasure against their natural enemies, pressures that have driven and continue to shape the speciation of these parasitoids. Using a representative sample of Sycophila parasitoid wasps, reared from 44 species of oak galls from 18 oak tree species across North America, in conjunction with mitochondrial DNA barcodes and Ultraconserved Elements (UCEs), we delimited these morphologically cryptic species and their host ranges. We find the majority of Sycophila are oligophagous, targeting multiple gall wasp species with similar gall morphologies. This result is congruent with previous research suggesting that parasitoid wasps such as Sycophila have adaptations to particular host phenotypes or extended phenotypes (e.g. size, spines, hairs, etc.) that grant them access to some hosts, while hosts with opposing or other traits reduce/exclude them as natural enemies. We also highlight the need for taxonomic revision of Sycophila, as many species cannot be identified morphologically or using molecular delimitation methods. UCEs (especially phased SNPs) overall seem to be more accurate in delimiting species than COI.