About Zhangixalus arboreus (Okada & Kawano, 1924)
Zhangixalus arboreus, which is also called the forest green tree frog and the Kinugasa flying frog, is a species of frog in the family Rhacophoridae. It is endemic to Japan, and has only been observed on the island of Honshu, at elevations ranging between 10 and 2350 meters above sea level.
The natural habitats of Z. arboreus are subtropical or tropical moist lowland forest, freshwater marshes, and irrigated land. These small tree frogs spend their entire adult lives in trees and forests. During breeding season, they gather around water sources to mate.
The species lays its eggs inside a batch of sponge-like foam that is suspended from a tree branch, usually above a pond, marsh, or slow-flowing stream. After tadpoles emerge from their eggs, they wiggle out of the foam and drop down into the water below. These foam egg batches are commonly seen hanging over ponds in the Japanese countryside during late spring. Sometimes the frogs accidentally lay their eggs over unsuitable bodies of water, including swimming pools, wells, and even buckets that hold rainwater.