The spotted lanternfly ( Lycorma delicatula) is an invasive insect from Asia that poses a significant threat to agricultural crops and trees due to its feeding habits. Understanding its life cycle, particularly its lifespan, is important for managing its spread.
Overall Lifespan
A spotted lanternfly typically completes its entire life cycle within approximately one year, undergoing a single generation annually. This cycle begins with overwintering as egg masses, which represent the longest phase. Active nymph and adult stages occur during warmer months, culminating in adults’ demise with cold weather.
Developmental Stages
The spotted lanternfly progresses through distinct developmental stages: egg, four nymphal instars, and the adult phase. Each stage involves molting, shedding its outer skin to grow.
Eggs are laid in masses, typically 1 to 1.5 inches long, containing 30 to 60 eggs. These masses are often covered with a gray, mud-like substance that can crack and fade. Laid in the fall, they remain dormant through winter.
Nymphs emerge from egg masses in late April or early May. There are four nymphal instars before they become adults. The first three instars are small, wingless, black with white spots, and 1/8 to 1/4 inch. These nymphs are active from May through July. The fourth and final nymphal instar (July through mid-August) becomes approximately 1/2 inch long, displaying a bright red body with black stripes and white spots. Nymphs are strong jumpers but cannot fly.
Adults begin to appear in July and can be observed until December. They are about 1 inch long and 1/2 inch wide, featuring gray forewings with black spots and black wing tips. When their wings are open, they reveal striking red hindwings with black spots and a white band. Adults are capable of short flights but often prefer to hop or jump, especially when startled.
Annual Cycle
The spotted lanternfly’s life cycle aligns closely with the seasons, with each stage occurring during specific periods. This annual progression ensures the species’ survival.
In spring (late April to May), overwintered egg masses begin to hatch. Newly emerged first instar nymphs are active, and as spring progresses into early summer, these nymphs continue to develop through their second and third instars. During this time, they are primarily black with white spots and feed on a wide range of host plants.
By summer (July to mid-August), the nymphs transition into their fourth instar, characterized by their red and black coloration. Adults begin to emerge around mid-July, marking the start of their reproductive phase. Adults are most active during the late summer and fall, feeding and preparing for reproduction.
In fall (September through November), adult spotted lanternflies engage in mating and egg-laying. Females deposit egg masses on various surfaces, ensuring the next generation survives winter. Adults generally perish with the first killing freeze, leaving behind overwintering egg masses to complete the annual cycle.