The Posttornoceratidae are Late Devonian goniatites (Ammonoidea) included in the superfamily Tornoceratoidea.

The Posttornoceratidae are derived from the Falcitornoceratidae through Exotornocers (Saunders et al. 2004) The family has been split into two subfamilies each containing two genera.

Posttornocerashas a subglobular to discoidal shell with a small, closed umbilicus and biconvex growth lines (Miller et al. 1964).

Exotornoceras is derived from Gundolficeras( Falcitornoceratinae) Discoclymenia is the type of the Discoclylemniinae, named by Hyatt in 1844.

Discoclymenia has a subglobular to discoidal shell with a small, closed umbilicus, like Sporadoceras but with additional adventitious lobes in the 1st lateral saddles.