Detection of field parasitism of the invasive spotted lanternfly (Lycorma delicatula) by native North American wasps using molecular tools

The management of invasive pest species frequently involves biological control to suppress the expanding pest populations. Although introduced natural enemies have been favored, the role of native fauna should not be overlooked. The spotted lanternfly ( Lycorma delicatula White; Hemiptera: Fulgoridae) is an invasive, polyphagous plant pest that has rapidly spread across eastern USA over the past decade. Biological control efforts of this pest largely focus on imported parasitoids, but there is increasing evidence of native wasps attacking spotted lanternfly eggs in the USA. To obtain a more accurate estimate of parasitism by one native wasp, Anastatus reduvii (Howard) (Hymenoptera: Eupelmidae), we developed a duplex real-time PCR (qPCR) assay capable of detecting A. reduvii DNA in spotted lanternfly eggs. In silico analysis and non-target testing using three additional Anastatus spp. and five potential host species indicated a low likelihood of false positive amplification. We applied the qPCR assay to spotted lanternfly eggs with parasitoid emergence holes collected from 11 locations in southeastern Pennsylvania, USA that encompass over 6000 km 2 . The assay detected more A. reduvii attacks than Sanger sequencing with universal primers (73 vs . 13 detections, respectively). This new monitoring tool enhances the detection and quantification of parasitism by native wasps, which—with new associations with the invasive pest through host adaptation—may contribute to meaningful biotic resistance and offer potential opportunity for conservation or augmentative biological control.