The shell of Meitianoceras is small and evolute .
Meitianoceras is a genus of ammonites in the ceratitid family Paraceltitidae that lived during the final stage of the Permian , from about 254 to 251 million years ago .
The shell of genus is small and evolute .
Meitianoceras is a genus of ammonites in the ceratitid family Paraceltitidae that lived during the final stage of the Permian , from about 254 to 251 million years ago .