Spotted Lanternfly Stages: What You Need to Know

The spotted lanternfly is a voracious, plant-eating insect with an interesting and complex life cycle. The adult lanternfly can be identified by its two pairs of spotted wings. However, they are not strong fliers and often jump instead of flying. Due to its appearance, this insect is often mistaken for a moth. The name itself is a bit of a misnomer — it is not a fly at all, and it has no glowing, lantern-like parts. It actually belongs to a group of insects called planthoppers.

Spotted lanternflies are indigenous to parts of southern China, Taiwan, and Vietnam. It has since been introduced in Japan, South Korea, and the United States, where it is considered an invasive species. It feeds on the sap of more than 70 plant species, including cherry trees, apple trees, birch trees, maple trees, poplar trees, grapevines, and lilacs. They pose a huge problem for orchards and agriculture by damaging or killing the plants. Spotted lanternflies produce a sticky substance called honeydew, which attracts other pests and encourages mold growth.

Egg Stage

The adult lanternfly is easy enough to identify when you know what signs to look for. However, the problem is it only spends a small portion of its life as an adult. The spotted lanternfly actually undergoes a complex transformation through several life stages. One whole generation takes about a year to complete. This process usually begins at some point between September and November.

After mating, the female lays large batches or rows of 20 to 60 eggs on smooth bark, fence posts, stones, furniture, or metal surfaces. In ideal conditions, a single tree can sometimes harbor up to 200 egg masses at a time. The female then covers the eggs in a white adhesive substance that becomes pink and gray as it begins to dry. This substance is often mistaken for mud or seed pods.

Instead of hatching immediately, however, the eggs will spend the entire winter in a state of suspended development. They are protected from the outside elements by the egg walls and the adhesive covering. They can survive exceptionally cold temperatures well below freezing. The parents do not play any role whatsoever in caring for the young, but the eggs are camouflaged on wood or metal surfaces to protect them from hungry predators.

Nymph Stages

When the eggs finally hatch around May or June, around 60% to 90% of them will have survived. The spotted lanternfly will now begin the first of four nymph life stages. An “instar” is a technical term for the life stages in between molts when the insect loses its skin and transitions into a new form. During the first instar, the spotted lanternfly measures about a quarter of an inch long. The shape of the insect leads many people to mistake it for some kind of tick. However, the white spots covering the body are an important clue to its identification.

This first nymph is already an excellent climber from the moment it hatches from the egg. If it falls from the tree due to strong wind or rough bark, it will start ascending again until it reaches all the way back up the trunk. Nymphs usually tolerate each other’s presence. However, if too many nymphs are eating from the same food source, then one may challenge another to a fight by raising its forelimbs. The challenged nymph will either flee or attempt to mount the challenger.

Both the second and third instars are fairly similar to the first in both appearance and behavior. The difference is the nymphs become progressively larger with each new stage. The end of the third molt takes place sometime between July and September. By the fourth instar, the nymph has a more distinctive appearance. It features a red upper body with white spots and black markings. The legs are also black with white markings. At this stage, it can measure up to three-quarters of an inch long.

Adult Stage

An adult spotted lanternfly can emerge as early as July or as late as September. They measure about an inch long. The adults are characterized by a black head and legs, a wide abdomen with yellow and brown stripes, and short orange antennae featuring needle-like tips. The females have an additional red tip at the end of the abdomen.

The easiest way to identify them, however, is by their two pairs of wings. The forewings have a pink or tan surface adorned with black spots for about two-thirds of their length. This is followed by a striped or brick-like pattern near the end. The hindwings are red with black spots, black, and white. When the insect is at rest, the wings are folded against the body. The upper wings mostly obscure the lower wings. When the insect is ready to jump or fly, it extends all four wings so it almost resembles a moth.

Many people try to dispose of adult spotted lanternflies, as they are easy to identify. Unfortunately, they can jump quickly or even fly away before they can be swatted. While these critters are harmless to humans and pets, they are harmful to plants, which is a good reason to get rid of them. The best way is to remove the eggs from the plants they are attached to by scraping them into a zippered plastic bag filled with alcohol. Then throw the plastic bag in the trash.

Dispersal and Mating

At some point after hatching, the spotted lanternfly will disperse from the place of its birth, usually traveling somewhere between 3-5 miles over its lifetime. Even the undeveloped nymphs have powerful hind legs to help them jump or climb. However, the adults are particularly mobile, thanks to their large wings. They have a habit of hitching a ride on vehicles, by either flying through a window or jumping into the back of a truck. Egg masses are also sometimes accidentally transported, particularly on outdoor items like firewood.

The spotted lanternfly will only spend a few months of its life as an adult. The main purpose of the adult phase is to reproduce. Unfortunately, there is little information about the lanternfly’s mating behavior, other than the fact that it takes place at the same time every autumn. It will only have a single opportunity to mate. The adult lanternflies die a short time later, allowing the next generation to thrive.