出典:Wikipedia
出典:『Wikipedia』 (2011/07/16 07:14 UTC 版)
Acrocanitidae is one of seven families of the Prionocerataceae families, a member of the Goniatitida order. They are an extinct group of ammonoid, which are shelled cephalopods related to squids, belemnites, octopuses, and cuttlefish, and more distantly to the nautiloids.