Siniperca chuatsi, the mandarin fish or Chinese perch (not to be confused with the mandarinfish), is species of temperate perch native to the Amur River basin and other rivers in China. Its back is yellow, green, or brown, with many irregular black spots and patches.
- Series: Fish
- Country: Mongolia
- Year: 1965-11-25
- Emission: Commemorative
- Perforation: comb 11
- Printing: Photogravure
- Size: 43 x 43 mm
- Face value: 5 Mongolian möngö
- Number of catalogue Michel: MN 398