China's Hainan tropical rainforest, classified as an island-type tropical rainforest, is a treasure trove of species. From the tropical lowland rainforest at altitudes below 800 meters to the montane cloud forest at altitudes above 1,300 meters, a wide variety of insects and amphibians grow and undergo metamorphosis in this paradise.

After Li Xia, the Beginning of Summer, the heavy rumbling of thunder announces the arrival of heavy rain, which hammers the leaves like the rolling of great timpani. The raindrops, as big as beans, penetrate through dense layers of foliage, soaking the soil of the rainforest.

After years of lying dormant underground, the cicada nymphs sense the arrival of summer and begin vigorously digging upwards with their strong front legs. Bursting out of the moist soil, they eagerly climb up the trees to undergo a magnificent metamorphosis, entering the final stage of their lives—the adult stage.

A cicada spreads its wings after emerging from its final stage of metamorphosis. (Photo: Li Tianping / Hainan Daily)

The male cicadas produce loud and resonant buzzing and squawking sounds, which can be harsh on the ear when a group of them choruses together. They use these calls to attract female cicadas and fulfill their final purpose—mating and reproducing, before quietly passing away.

A cicada moving on a branch. (Photo: Li Tianping / Hainan Daily)

In the evening, a katydid hangs in the air on its molted outer skin. Once its wings have stretched and hardened, it will fly for the first time in its life.

A newly molted katydid has grown wings. (Photo: Li Tianping / Hainan Daily)

Similar to katydids, cicadas also go through three stages in their lifetime, from egg to nymph to adult. The morphology and basic behavioral characteristics of their larvae and adults are also quite similar.

A katydid nymph perches on a bamboo leaf. (Photo: Li Tianping / Hainan Daily)

A damselfly rests on a plant leaf. (Photo: Li Tianping / Hainan Daily)

On the plants of the Urticaceae—the nettle family—in the Hainan Tropical Rainforest National Park, a spiky-looking insect can often be observed. However, visitors who see it for the first time find it difficult to associate it with the beautiful Acraea issoria, the yellow coster butterfly.

A yellow coster caterpillar. (Photo: Li Tianping / Hainan Daily)

A yellow coster butterfly emerges from its chrysalis. (Photo: Li Tianping / Hainan Daily)

With large, protruding eyeballs and wide field of vision, frogs can quickly detect any insect movement and promptly target their prey, leaping or lunging forward to seize their meal. Hence, butterflies, dragonflies, grasshoppers, and other insects that have completed their metamorphosis need to be very cautious, because even a minor slip renders them vulnerable to the long tongues of frogs, prematurely ending the most beautiful stage of their lives.

A tadpole of the ornate narrow-mouthed frog (Microhyla ornata) swims in a stream. (Photo: Li Tianping / Hainan Daily)

A fine-spined frog (Hylarana spinulosa) during metamorphosis. (Photo: Li Tianping / Hainan Daily)

Two large odorous frogs (Odorrana graminea) mate, prompting the female to ovulate. (Photo: Li Tianping / Hainan Daily)

作者：David Janke