The spotted lanternfly, Lycorma delicatula, is an invasive planthopper that has significantly impacted agricultural and natural ecosystems in various regions, particularly in the United States. First detected in Pennsylvania in 2014, it has since spread across at least 18 states, posing a threat to vineyards, orchards, and hardwood trees. Understanding the role of natural enemies, specifically other insects, is important for developing effective strategies to manage its growing populations.
Generalist Insect Predators
Various insect species act as generalist predators on spotted lanternflies. Praying mantises, including the Carolina and Chinese mantises, are prominent examples. These ambush predators capture both adult and nymph lanternflies with their specialized forelegs, consuming them even if the lanternflies have fed on the tree of heaven. Spined soldier bugs, a type of predatory stink bug, also prey on spotted lanternflies. These bugs, native to North America, actively hunt and consume lanternflies across all life stages.
Assassin bugs, such as the wheel bug, also prey on spotted lanternflies. The wheel bug uses its piercing, beak-like mouthpart to liquefy the insides of its prey, then consuming the fluids. Spiders are frequently observed generalist predators that capture spotted lanternflies in their webs. Other insects like ants and yellow jackets have been reported to feed on lanternflies.
Specialized Insect Parasitoids
Beyond generalist predators, certain insect species are specialized parasitoids of spotted lanternflies. Parasitoids employ a distinct strategy, laying their eggs on or inside the host, with the developing larvae eventually consuming the host. In the spotted lanternfly’s native range in Asia, parasitic wasps play a significant role in regulating its populations.
One example is Anastatus orientalis, an egg parasitoid that lays its eggs within spotted lanternfly egg masses. This wasp has a flexible life cycle and is being studied for its potential in biological control programs in invaded regions. Another parasitoid, Dryinus browni, targets spotted lanternfly nymphs. While Ooencyrtus kuvanae, a chalcid wasp, has also been documented to parasitize spotted lanternfly egg masses, its current impact on reducing populations is not high.
The Role of Natural Enemies in Lanternfly Control
Insect predators and parasitoids contribute to the natural control of spotted lanternfly populations, but their effectiveness in invaded regions has limitations. In their native habitats, specialized parasitic wasps help keep lanternfly numbers in check. However, in newly invaded areas like the United States, the absence of these co-evolved specialized enemies allows the spotted lanternfly to spread rapidly.
While native generalist predators, such as mantises and spined soldier bugs, feed on lanternflies, they are often not sufficient to control large infestations on their own. The spotted lanternfly’s rapid reproduction rate can overwhelm the predatory capacity of local insects. The lanternfly’s ability to sequester defensive compounds from its preferred host, the tree of heaven, might offer some protection against certain predators. Therefore, while natural enemies are a valuable component, they are considered part of a broader integrated pest management strategy rather than a standalone solution.