Skip to main content
ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Systematic Entomology Laboratory » Research » Publications at this Location » Publication #392245

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: Ormyrus labotus (Hymenoptera: Ormyridae): Another generalist that should not be a generalist is not a generalist

item Gates, Michael
item SHEIKH, SOFIA - University Of Iowa
item WARD, ANNA - University Of Iowa
item ZHANG, YUANMENG MILES - University Of Central Florida
item DAVIS, CHARLES - Rice University
item ZHANG, LINYI - Rice University
item EGAN, SCOTT - Rice University
item FORBES, A - University Of Iowa

Submitted to: Insect Systematics and Diversity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/4/2022
Publication Date: 2/16/2022
Citation: Gagne, R., Sheikh, S., Ward, A., Zhang, Y., Davis, C., Zhang, L., Egan, S., Forbes, A.A. 2022. Ormyrus labotus (Hymenoptera: Ormyridae): Another Generalist That Should not be a Generalist is not a Generalist. Insect Systematics and Diversity. 6:1-14.

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: Several recent reappraisals of supposed generalist parasite species have revealed hidden complexes of species, each with considerably narrower host ranges. Parasitic wasps that attack gall-forming insects on plants have life history strategies that are thought to promote specialization, and though many species are indeed highly specialized, others have been described as generalist parasites. Ormyrus labotus Walker (Hymenoptera: Ormyridae) is one such apparent generalist, with rearing records spanning more than 65 host galls associated with a diverse set of oak tree species and plant tissues. We pair a molecular approach with morphology, host ecology, and phenological data from across a wide geographic sample to test the hypothesis that this supposed generalist is actually a complex of several more specialized species. We find 16–18 putative species within the morphological species O. labotus, each reared from only 1–6 host gall types, though we identify no single unifying axis of specialization. We also find cryptic habitat specialists within two other named Ormyrus species. Our study suggests that caution should be applied when considering host ranges of parasitic insects described solely by morphological traits, particularly given their importance as biocontrol organisms and their role in biodiversity and evolutionary studies.