The rain frog is a species of amphibian belonging to the rain frog family. It is distributed in the northern part of South Korea and Mongolia, the northeastern part of China, and the southern part of the Russian Far East. The adult male body length of the rain frog is 2.6 to 4.5 centimeters, and the adult female body length is 2.6 to 4.1 centimeters. However, the average body length of adult males is 3.1 centimeters, and the average body length of adult females is 3.5 centimeters. They have disc-shaped objects on their toes for climbing. This frog is able to lay eggs or fertilize at the age of 3 or 4. They feed on various insects, mainly searching for food at dawn and dusk, but if insects approach, they also feed during the day.

The breeding season of Japanese tree frogs is from April to August. At this time, male frogs migrate to still water areas such as low altitude rice paddies and wetlands to chirp loudly, laying about 250-800 eggs at a time. During the non breeding season, it often calls before rain and is a true rain frog.

The breeding season of Japanese tree frogs is from April to August. At this time, male frogs migrate to still water areas such as low altitude rice paddies and wetlands to chirp loudly, laying about 250-800 eggs at a time. During the non breeding season, it often calls before rain and is a true rain frog.

The Northeast Rain Frog (scientific name: Hyla japonica) is a species of amphibian in the Rain Frog family. Distributed in Hokkaido and Yakushima in Japan, as well as along the Heilongjiang River in North Korea and Northeast China, including Heilongjiang, Liaoning, Jilin, and Inner Mongolia. The type locality of this species is in Japan. In 1990, Japanese astronaut Toyohiro Akiyama brought some Northeastern rain frogs to the Soviet Union's Mir space station.