A critically endangered fish whose swim bladder is believed to cure illnesses has been caught and sold for more than $500,000 in China.

The 135-kilogram Chinese bahaba (Bahaba taipingensis), the first fish of its species caught in at least a year, was thought to be more than 50 years old. A fishery in Guangdong Zhanjiang purchased the fish for 3.45 million yuan.

According to the IUCN Red List of Threatened Species, the Bahaba's swim bladder "is highly appreciated for its medicinal properties and as a general tonic for health." Its use in traditional Chinese medicine resulted in the species being heavily overfished, to the point where any catch is widely reported in China's media.

Bahaba are endemic to the East China and South China seas. According to the IUCN, no spawning populations of the fish are known, and "there are likely to be few or no refuges remaining for recovery."

Image: Bahaba taipingensis, via Fishbase.us