The tiny parasitoid wasp Dryinus sinicus (adult female shown here) has emerged as a leading candidate for long-term biological control of the invasive spotted lanternfly. A natural enemy of the spotted lanternfly in Asia, Dryinus sinicus is currently being evaluated by researchers in the U.S. and offers hope for reducing spotted lanternfly populations naturally and potentially easing reliance on insecticides. (Photo originally published in Wang et al. 2026, Annals of the Entomological Society of America)

By Carolyn Bernhardt

Since experts first detected the spotted lanternfly (Lycorma delicatula) in Pennsylvania in 2014, the invasive pest has sucked the sap out of various plants across at least 18 eastern and midwestern states in the U.S., including some key crops such as grapevines and fruit trees. Lanternflies have already left a wake of destruction in vineyards in South Korea, and researchers fear they could have similar impacts in other wine-producing regions, including the U.S. and Europe, which offer the lanternfly plenty of suitable habitat.

In response, many vineyard managers in the U.S. have relied heavily on insecticides, an imperfect tool with a few key downsides. In addition to their negative environmental ramifications, insecticides are also not effective for long, as pests quickly reinvade from nearby trees and other host plants.

Because the spotted lanternfly feeds on many different plants and can spread easily across large areas, researchers say long-term control will likely require broad, sustainable management strategies. So, scientists are now turning to a potential biological control option.

While biological control agents such as predator or parasitoid insects typically do not eradicate pests completely, they suppress populations to less-damaging baseline levels. Because the spotted lanternfly feeds on a wide range of plants, reducing its populations requires an area-wide approach across diverse habitats surrounding agricultural landscapes.

In the spotted lanternfly’s native range, the parasitoid wasp Dryinus sinicus is a natural enemy, targeting lanternflies during their nymph stage. Using a series of controlled laboratory experiments at a U.S. Department of Agriculture quarantine facility, a team of experts studied the development, reproduction, and hunting behavior of Dryinus sinicus. As a first major step in the ongoing efforts to determine whether the wasp could serve as a safe and effective long-term control strategy for the spotted lanternfly in the U.S,, the research team published its findings in April in Annals of the Entomological Society of America.

A Spotted Lanternfly Nymph’s Worst Nightmare

In this study, experts analyzed over 10,000 lanternfly nymphs to determine which factors influenced wasps’ ability to control spotted lanternfly populations. They documented the wasp’s complete immature development, showing that it passes through five larval stages before pupating. Once a female wasp lays an egg on a nymph, the larva feeds externally while embedded in the host, leading to the nymph’s eventual death after the larva consumes its internal tissues and emerges.

In laboratory conditions, female wasps lived about two months on average, with larger females producing more eggs and those feeding on multiple hosts reproducing more effectively. Wasps continued to lay eggs throughout adulthood, particularly when lanternfly hosts were available.

Throughout their lives, individual female wasps parasitized an average of 137 to 175 nymphs. While they commonly laid multiple eggs in a single host, most nymphs contained only one developing wasp. Additionally, females directly killed and consumed around 20 nymphs for nutrition during their lifespan.

The tiny parasitoid wasp Dryinus sinicus (adult female shown here) has emerged as a leading candidate for long-term biological control of the invasive spotted lanternfly. A natural enemy of the spotted lanternfly in Asia, Dryinus sinicus is currently being evaluated by researchers in the U.S. and offers hope for reducing spotted lanternfly populations naturally and potentially easing reliance on insecticides. Researchers at the U.S. Department of Agriculture studied the development, reproduction, and hunting behavior of D. sinicus, and they found that adult females directly killed and consumed around 20 spotted lanternfly nymphs for nutrition during their lifespan. They also sometimes laid multiple eggs on lanternfly nymphs for their offspring to parasitize, as charted here. Shown at right are three D. sinicus eggs laid under a lanternfly nymph wing pad (A), two D. sinicus larvae growing on the exterior of a lanternfly nymph (B), and a lanternfly nymph with four D. sinicus larvae growing on it. (Figure originally published in Wang et al. 2026, Annals of the Entomological Society of America)

Safety, Specificity, and Superparasitism

Dryinus sinicus is still bogged down with quarantine restrictions, so researchers working with the wasp must rear it on spotted lanternflies on potted host plants in the lab. Here, a few challenges arise. For starters, using small potted host plants in limited quarantine space makes it more difficult to produce a larger number of wasps, as well as healthy ones. USDA scientists are now working on developing more efficient rearing methods.

Experts working on this project say that perhaps the biggest hurdle for any classical biological control program is ensuring the introduced agent doesn’t become a pest by attacking native insects. Other USDA researchers have recently completed host-specificity testing, showing that the wasp poses no risk to nontarget species. They have also submitted a petition to release this agent from its quarantine status. The experts expect this parasitoid will be permitted for release after regulatory reviews over the next few years.

In the meantime, several important questions remain. Experts still do not fully understand how the female wasp’s claw-like grasping structures, which it uses to capture hosts, function during attacks, or how the structures evolved alongside the defensive behaviors of spotted lanternflies and other hosts. A better understanding of how this appendage developed in the first place and exactly how it works could further inform future management tactics that employ the wasp.

The study also raised new questions about the wasp’s reproduction. Researchers found that laying eggs and feeding on hosts appear to stimulate additional egg production in the wasp, but the biological “why” behind this process remains murky. Future studies, the team says, could explore how nutrients gained through feeding influence egg development and how host scarcity affects wasp reproduction.

Another key area for future research is superparasitism, when females lay multiple eggs in the same host. Although the behavior happened fairly often in the lab, scientists do not yet know why the wasps do this, how common it is in nature, or how often multiple offspring can successfully survive in a single spotted lanternfly.

Once experts can take this research into the field for further testing, they suspect environmental conditions, climate, host availability, and seasonal timing will all significantly affect the wasp’s effectiveness. So, the authors emphasize that more field studies are vital. They also note that relatively little is known about related Dryinidae wasp species as a whole, opening the door to broader studies comparing the development, reproduction, and biological control potential of different species within the family.

But for now, the team considers Dryinus sinicus the most promising biological control agent against the spotted lanternfly. Although they won’t know for sure how effective the wasp is against U.S. spotted lanternfly populations until it has been released and permanently established on the landscape, lanternfly populations are rarely considered pests in China anymore, thanks to D. sinicus and Anastatus orientalis (an egg parasitoid) naturally keeping them in check.

While reducing baseline pest levels is ideal for forests or parks, specialty crop producers have much lower tolerance for lanternfly damage. Farmers will still need localized chemical options to protect their high-value crops. So, the experts say, biological control is really an investment for long-term management of what promises to be a long-term problem. Thankfully, more systematic evaluation of this wasp’s suitability for the biological control of the spotted lanternfly is still underway, and this is just the first study borne from the evaluation in the U.S.

Carolyn Bernhardt, M.A., is a freelance science writer and editor based in Rhinelander, Wisconsin. Email: [email protected].