Moulting in Cicada: From Shell to Wings

In my birding trip to Thailand, I encountered many shed exoskeletons of cicadas. At that time, I knew very little about these fascinating insects and eagerly photographed what I found. After photographing two or three exoskeletons, I realized to my dismay that I was snapping lifeless shells! Later I learned about the life cycle of cicadas and their moulting process.

Cicadas are large insects known for the courtship calls of males. They belong to the family Cicadidae, which include over 3000 sound-producing species. They inhabit world’s tropical and temperate regions, including deserts, grasslands, and forests. Ranging from 2 to 5 cm in size, cicadas have short antennae, two pairs of transparent wings, and prominent compound eyes. They do not bite or sting.

All cicadas have a life cycle with three stages: egg, nymph, and adult. Adult females lay eggs in woody plant tissues. Six to eight weeks later, small white m ushy nymphs hatch and fall to the ground. Using their strong front legs for digging, they burrow into the soil and live near roots, drinking the sap from the root xylem.

Cicadas go through 5 nymph stages, each time moulting their exoskeleton and growing larger. This process takes 1–5 years, depending on food availability and environmental conditions. At the end of the fifth stage, the nymphs emerge out of the ground, crawl up a tree, and undergo their final moulting. After their new exoskeleton hardens, they start looking for mates.

Adult male cicadas emerge in multitudes and sing simultaneously to attract females, creating a deafening noise. After mating, the females lay eggs, and soon after, both the males and the females die, littering the forest floor. Their decomposing bodies enrich the soil, benefiting plants and the new nymphs.

While I was herping at Amboli (a small village and an ecological hotspot nestled in the Western Ghats, Maharashtra), India, our guide, Vipul Ramanujan, suddenly became hyper-excited. He had found a cicada nymph on the brink of moulting into a fully grown adult. We quickly readied our cameras and gathered around to capture the entire process. In this blog, I will share how it unfolded.

The cicada nymph firmly anchored its legs to a tree trunk, its dull brown exoskeleton blending with the bark.

Despite heavy rain, we were concerned about the nymph falling off. Vipul reassured us that its grip was secure. With our eyes fixed on it, we soon saw a crack slowly forming along its back.

With deliberate, almost painstaking movements, the cicada began to wriggle free from its confining shell. The process unfolded slowly and delicately.

As the cicada emerged, it was almost unrecognizable from its previous stage. Its body was soft and almost translucent, with hints of green starting to show.

It hung on to the now empty exoskeleton, resting and gathering strength for the next crucial stage.

At first, the cicada’s wings were crumpled and limp, like delicate pieces of wet tissue paper.

Gradually, the legs emerged, still too soft to support the insect’s weight.

The cicada began flexing its legs to stimulate blood flow, and slowly they hardened and gained strength.

By now, the legs had sufficiently hardened to support its body weight, allowing the cicada to grasp the shed exoskeleton and stand upright.

Gradually, as the cicada pumped fluid into its wings, they began to expand. Veins filled with fluid, giving structure and shape to the once-weak wings. Slowly but surely, the wings extended and hardened, turning a beautiful shade of green.

Vipul explained that it would take a few more hours for the new exoskeleton to harden fully so the cicada could fly. The cicada remained motionless, letting nature complete the process. With night approaching, we reluctantly left, needing rest.

Witnessing the moulting process of a cicada nymph was awe-inspiring. Amidst our busy lives, we often have no time to admire the countless natural marvels unfolding around us. By slowing down and taking the time to observe the world around us, we can find a deeper connection to the natural world and enrich our lives with its myriad marvels.

What is this life if, full of care,

We have no time to stand and stare.

………………………………………………..

A poor life this if, full of care,

We have no time to stand and stare.

(William Henry Davies, “Leisure”)