1958  Ponticeras retorquatum Glenister, p.66, pl.5 fig.2,3,  textfig.1A,2B.
     1971  Probeloceras retorquatum.-Clausen, p.189, textfig.3f.
     2002  Maternoceras retorquatum.-Korn & Klug: Fig.106 C, D, E.
     2009  Maternoceras retorquatum.-Becker & House: 421.