What you eat is what we need: using ants to detect spotted lanternfly (<i>Lycorma delicatula</i>) DNA

Abstract

BACKGROUND: Early detection of invasive species such as the spotted lanternfly (SLF, Lycorma delicatula) 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 the ant-derived DNA (antDNA) approach, utilizing ants as ‘honeydew samplers’ to detect SLF DNA. We validated the effectiveness of this method through three experiments.

RESULTS: Using SLF-specific polymerase chain reaction (PCR), we consistently detected SLF DNA in ants foraging or nesting near SLF infestations. We then showed that after a single honeydew meal, SLF DNA persisted in ants for at least 5 days, even when, subsequently, ants were fed plain honey solution. Lastly, ants collected from honey-baited lure stations along transects radiating from SLF infestations yielded positive detections up to 100 mfrom the core infestations, demonstrating the method's extensive detection range. These findings confirm that ants, through their active foraging and feeding on environmental honeydew and ability to retain the ingested material, are highly reliable SLF DNA samplers.

CONCLUSION: Combined with ants' ecological dominance and the ease and low cost of ant collection, the antDNA method offers a sensitive, efficient and practical alternative to traditional, labor-intensive approaches for detecting SLF and potentially other honeydew-producing insects.