Something similar to a small jellyfish found in Qingshan Reservoir in Chongyang, Hubei Province. What is this?

Freshwater jellyfish (peach blossom jellyfish)

Several rare coelenterates living in fresh water. Only 9 species are found in the world, 7 of which are from China. According to modern zoology, it was first discovered in Britain at 1880 and in Yichang, China at 1907. China called it "Peach Blossom Fish" in ancient times and "Peach Blossom Jellyfish" in modern times. It was recorded in Chinese ancient books as early as the thirty-seventh year of Wanli in Ming Dynasty (i.e. 1609), so our understanding of freshwater jellyfish was more than 270 years earlier than that of European and American countries. Freshwater jellyfish mostly live in small rivers and ponds isolated from rivers, and their bodies are hemispherical, milky and translucent. The umbrella rim has tentacles, which can be divided into several levels according to the length and landing position, with 4 spokes and 1 loop. The colors of gonads are green, brownish yellow, red and black. Freshwater jellyfish in China are mainly distributed in the Yangtze River basin and have been found in 50 counties and cities in 13 province. China Peach Blossom Jellyfish, Sichuan Peach Blossom Jellyfish and Xinjiang Peach Blossom Jellyfish are endemic to China. There are many kinds and wide distribution of freshwater jellyfish in China, which is incomparable to other countries. Considering the species and distribution of peach blossom jellyfish and the observation and description of peach blossom jellyfish in ancient China, it is well proved that peach blossom jellyfish originated in China, which is easily accepted by people.

I hope it helps you.