Eopachydiscus Wright, 1955 is confirmed as the earliest, Upper Albian representative of the Pachydiscidae, derived in all probability from a bullate member of the Beaudanticeratinae and giving rise to the Cenomanian-Coniacian Lewesiceras Spath, 1939. Nuclei of Eopachydiscus are ribbed, tuberculate, and constricted, showing even at this stage and date typical pachydiscid ornament; the evolution of Lewesiceras simply involved retention of these features into middle growth. The suggestion that t...