title: Pachyceras
text: # Pachyceras
  
  Pachyceras is a genus of perisphinctoid ammonites from the Middle Jurassic, upper Callovian stage, and is the type genus for the family Pachyceratidae. The shell is involute, subglobular, with a deep umbilicus and flattened flanks that slope toward a more narrowly rounded venter, and covered by low, widely spaced ribs.
  
  ## Distribution
  
  Jurassic deposits of Egypt, France, India, Saudi Arabia and Switzerland.
  
  