What you eat is what we need: using ants to detect spotted lanternfly (Lycormadelicatula) DNA

Authors: LIN, WEI-JIUN - National Taiwan University; LIU, FANG-LING CHLOE - Virginia Polytechnic Institution & State University; HUANG, XUN-YI - National Taiwan University; DEL POZO-VALDIVIA, ALEJANDRO - Virginia Polytechnic Institution & State University; Leskey, Tracy; SCOTTY YANG, CHIN-CHENG - Virginia Polytechnic Institution & State University

Submitted to: Pest Management Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/24/2025
Publication Date: 4/24/2025
Citation: Lin, W., Liu, F., Huang, X., Del Pozo-Valdivia, A.I., Leskey, T.C., Scotty Yang, C. 2025. What you eat is what we need: using antsto detect spotted lanternfly (Lycormadelicatula) DNA. Pest Management Science. https://doi.org/10.1002/ps.8814.
DOI: https://doi.org/10.1002/ps.8814

Interpretive Summary: Early detection of spotted lanternfly (SLF) has been successfully achieved by collecting and amplifying environmental DNA (eDNA) left behind by nymphs and adults. Unfortunately, abiotic conditions such as rain and morning dew can degrade the available DNA left behind by this invasive insect. Moreover, collecting the eDNA is a very labor-intensive process that involves rinsing host plants with purified water, collecting the water rinsate, and then filtering the eDNA from the sample. Here, we used a simple approach to circumvent both labor and abiotic condition shortcomings. We baited small tubes with honey, collecting foraging ants. The ants were then used as a source for SLF DNA. This unique approach yield positive detections for up to 100 meters from infestation sites, and subsequent experiments showed ants retain SLF DNA for at least five days. This approach opens simple, novel methods for detecting invasive species in the environment.

Technical Abstract: Early detection of invasive species such as the spotted lanternfly (Lycorma delicatula, SLF) is critical for effective management including eradication efforts and limiting further spread. SLF excretes honeydew containing detectable DNA, providing a unique opportunity to leverage environmental DNA (eDNA) for its detection. This study introduces a novel approach, ant-derived DNA (aDNA), which utilizes ants as SLF “honeydew samplers” to detect SLF DNA. We validated the effectiveness of the aDNA method through three experiments. Using SLF-specific PCR, we consistently detected SLF DNA in ants actively foraging or nesting near SLF infestations. We then demonstrated that after a single honeydew meal, SLF DNA persisted in ants for at least five days, even when, subsequently, ants were fed plain honey solution. Lastly, ants collected from honey-baited lure stations along transects radiating from SLF infestation sites yielded positive detections up to 100 meters from the core infestation, demonstrating the method’s extensive detection range based on foraging ant activity. These findings confirm that ants, through their active foraging and feeding on environmental honeydew and ability to retain this ingested SLF-produced material, are highly reliable SLF DNA samplers. Combined with ants’ ecological dominance and the ease and low cost of ant collection using honey-baited lure stations, the aDNA method offers a sensitive, efficient and practical alternative to traditional, labor-intensive eDNA-based approaches for detecting SLF and potentially other sap-sucking, honeydew producing pest species.