Pseudorthocerataceae is an extinct superfamily of actively mobile carnivorous cephalopod, essentially a Nautiloid, that lived in what would be North America, Europe, Australia, and Asia during the Ordovician from 490—445.6 mya, existing for approximately 44.4 million years.
[1] Pseudorthocerataceae was named by Sweet (1964).
[2][3] The shell is usually long, and may be straight ("orthoconic") or gently curved.
In life, these animals may have been similar to the modern squid, except for the long shell.
Fossil distribution is exclusive to Sardinia, Wisconsin USA, and northern Ontario, Canada.